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A list of published
studies showing links between radition from mobile phones and masts and ill
health
Contents:
1. General Neurological Complaints (12)
2. Measured Neurological Effects (41)
3. Measured Neurological Function (16)
4. Observed Whole Body Response (2)
5. Measured Changes to Body Chemistry (9)
6. Measured Cellular Chemistry Alterations
(21)
7. Cellular Damage and Cell Death (23)
8. Embryo Mortality (1)
9. Blood Brain Barrier (3)
10. Brain Tumours (15)
11. General Cancer (2)
12. Immune Response (2)
13. Effects on Melatonin (9)
14. Sperm Quality (4)
15. Miscellaneous Studies (24)
16. Epidemiological Phone Mast Studies (7)
17. Phone masts' effects on animals (3)
Total of 194
studies
1. General Neurological complaints:
headache, dizziness, extreme irritation, shaking in
the hands, speaking falteringly, forgetfulness, neuro-psychological discomfort,
increase in the carelessness, decrease of the reflex, fatigue, tension, sleep
disturbance, ear ache and clicking sound in the ears
1
Al-Khlaiwi T,
Meo SA. Association of mobile phone radiation with fatigue,
headache, dizziness, tension and sleep disturbance in Saudi population. Saudi Med J. 25(6):732-736, 2004.
OBJECTIVE: The widespread use of mobile phones has been increased over the past
decade; they are now an essential part of business, commerce and society. The
use of mobile phones can cause health problems. Therefore, the aim of the
present study is to investigate the association of using mobile phones with
fatigue, headache, dizziness, tension and sleep disturbance in the Saudi
population and provide health and social awareness in using these devices.
METHODS: This study was conducted in the Department of Physiology, College of
Medicine, King Saud University, Riyadh, Kingdom of Saudi Arabia during the year
2002 to 2003. In the present study, a total of 437 subjects (55.1% male and
39.9% female) were invited, they have and had been using mobile phones. A
questionnaire was distributed regarding detailed history and association of
mobile phones with health hazards. RESULTS: The results of the present study
showed an association between the use of mobile phones and health hazards. The
overall mean percentage for these clinical findings in all groups were headache
(21.6%), sleep disturbance (4.%), tension (3.9%), fatigue (3%) and dizziness
(2.4%). CONCLUSION: Based on the results of the present study, we conclude that
the use of mobile phones is a risk factor for health hazards and suggest that
long term or excessive use of mobile phones should be avoided by health
promotion activities such as group discussions, public presentations and
through electronic and print media sources.
2
Balikci K, Cem
Ozcan I, Turgut-Balik D, Balik HH. A survey study on some
neurological symptoms and sensations experienced by long term users of mobile
phones. Pathol Biol
(Paris).
53(1):30-34, 2005.
A survey study was
conducted to investigate the possible effects of mobile phone on headache,
dizziness, extreme irritation, shaking in the hands, speaking falteringly,
forgetfulness, neuro-psychological discomfort, increase in the carelessness,
decrease of the reflex and clicking sound in the ears. There is no effect on
dizziness, shaking in hands, speaking falteringly and neuro-psychological
discomfort, but some statistical evidences are found that mobile phone may
cause headache, extreme irritation, increase in the carelessness,
forgetfulness, decrease of the reflex and clicking sound in the ears.
3
Garcia Callejo FJ, Garcia Callejo F, Pena Santamaria
J, Alonso Castaneira I, Sebastian Gil E, Marco Algarra J. [Hearing level and
intensive use of mobile phones] Acta
Otorrinolaringol Esp. 56(5):187-191, 2005.
[Article in
Spanish]
INTRODUCTION: Wide studies and substantial controversies build on utilization
of actual mobile phones and appearance of systemic disorders or even tumours,
but there is no knowledge about an eventual involvement on early hearing loss.
PATIENTS AND METHODS: In a group of three hundred and twenty-three healthy and
normoacoustic volunteers who were usual costumers of mobile phones an
audiometric evaluation was made at the beginnig of its use and three years
later, inquiring about the periods of time per day and year employed on direct
contacts with phone. A healthy and normoacoustic control group of non users was
studied too. RESULTS: Cases carried out 24.3 +/- 8.2 active contacts, reaching
50.4 +/- 27.8 days of mobile phone employment in three years. Audiometric curve
was similar in cases and controls at the beginning of the study. After this
follow-up, cases showed an increase on hearing threshold between 1 and 5 dB HL
more than controls in speech tones (p<0.001). Moreover, there was a trend to
correlate time of phone use to hearing impairment, but this finding did not
result statistically significative. CONCLUSIONS: Frequent management of mobile
phones in a middle period of time allows to detect a mild hearing loss, but the
cause of this disorder keeps unclear.
4
Hocking, B, Preliminary report: symptoms associated
with mobile phone use. Occup Med (Lond);48(6):357-360,
1998.
Mobile
phone use is ubiquitous, although the alleged health effects of low level
radio-frequency radiation (RFR) used in transmission are contentious. Following
isolated reports of headache-like symptoms arising in some users, a survey has
been conducted to characterize the symptoms sometimes associated with mobile
phone usage. A notice of interest in cases was placed in a major medical
journal and this was publicized by the media. Respondents were interviewed by
telephone using a structured questionnaire. Forty respondents from diverse
occupations described unpleasant sensations such as a burning feeling or a dull
ache mainly occurring in the temporal, occipital or auricular areas. The symptoms often began minutes
after beginning a call, but could come on later during the day. The symptoms
usually ceased within an hour after the call, but could last until evening.
Symptoms did not occur when using an ordinary handset, and were different from
ordinary headaches. There were several reports suggestive of intra-cranial
effects. Three respondents reported local symptoms associated with wearing
their mobile phone on their belts. There was one cluster of cases in a
workplace. Seventy-five per cent of cases were associated with digital mobile
phones. Most of the respondents obtained relief by altering their patterns of
telephone usage or type of phone. Cranial and other diverse symptoms may arise
associated with mobile phone usage. Physicians and users alike should be alert
to this. Further work is needed to determine the range of effects, their
mechanism and the possible implications for safety limits of RFR.
5
Meo SA, Al-Drees AM. Mobile
phone related-hazards and subjective hearing and vision symptoms in the Saudi
population. Int J Occup Med Environ Health. 18(1):53-57, 2005
OBJECTIVES: Over the past decade utilization of mobile phones has dramatically
increased. They are now an essential part of business, commerce, and
communication, however, their use may lead to health problems. Therefore, the
present study was designed to investigate a link between the use of mobile
phones and hearing and vision symptoms in the Saudi population and also to
contribute to the increase in social awareness of health problems associated
with the use of these devices. MATERIALS AND METHODS: A total of 873 (57.04% of
males and 39.86% of females) subjects using mobile phones were invited to
participate in the presented study. A structured questionnaire was distributed
among them to collect a detailed medical history. The Chi-square test was
employed to observe the relationship between duration of calls and hearing and
vision complaints. RESULTS: The present study showed an association between the
use of mobile phones and hearing and vision complaints. About 34.59% of
problems were related with impaired hearing, ear ache and/or warmth on the ear,
and 5.04% of complaints with the decreased and/or blurred vision. CONCLUSIONS:
It is concluded that the use of mobile phone is a health risk factor, and thus
it is suggested that excessive use of mobile phones should be avoided and social
awareness increased through health promotion activities, such as group
discussions or public presentations and via electronic and printed media
sources.
6
Wilen J,
Sandstrom M, Hansson Mild K. Subjective symptoms among mobile phone users-A
consequence of absorption of radiofrequency fields? Bioelectromagnetics 24(3):152-159, 2003.
In a previous epidemiological study, where we studied the prevalence of
subjective symptoms among mobile phone (MP) users, we found as an interesting
side finding that the prevalence of many of the subjective symptoms increased
with increasing calling time and number of calls per day. In this extrapolative
study, we have selected 2402 people from the epidemiological study who used any
of the four most common GSM MP. We used the information about the prevalence of
symptoms, calling time per day, and number of calls per day and combined it
with measurements of the Specific Absorption Rate (SAR). We defined three
volumes in the head and measured the maximum SAR averaged over a cube of 1 g
tissue (SAR(1g)) in each volume. Two new exposure parameters Specific
Absorption per Day (SAD) and Specific Absorption per Call (SAC) have been
devised and are obtained as combinations of SAR, calling time per day, and
number of calls per day, respectively. The results indicates that SAR values
>0.5 W/kg may be an important factor for the prevalence of some of the
symptoms, especially in combination with long calling times per day.
7
Wilen J, Johansson A, Kalezic N, Lyskov E, Sandstrom M. Psychophysiological
tests and provocation of subjects with mobile phone related symptoms. Bioelectromagnetics.
2005 Nov 22; [Epub ahead of print]
The aim of the present study was to investigate the effect of exposure to a
mobile phone-like radiofrequency (RF) electromagnetic field on persons
experiencing subjective symptoms when using mobile phones (MP). Twenty subjects
with MP-related symptoms were recruited and matched with 20 controls without
MP-related symptoms. Each subject participated in two experimental sessions,
one with true exposure and one with sham exposure, in random order. In the true
exposure condition, the test subjects were exposed for 30 min to an RF field
generating a maximum SAR(1g) in the head of 1 W/kg through an indoor base
station antenna attached to a 900 MHz GSM MP. The following physiological and
cognitive parameters were measured during the experiment: heart rate and heart
rate variability (HRV), respiration, local blood flow, electrodermal activity,
critical flicker fusion threshold (CFFT), short-term memory, and reaction time.
No significant differences related to RF exposure conditions were detected.
Also no differences in baseline data were found between subject groups, except
for the reaction time, which was significantly longer among the cases than
among the controls the first time the test was performed. This difference
disappeared when the test was repeated. However, the cases differed
significantly from the controls with respect to HRV as measured in the
frequency domain. The cases displayed a shift in low/high frequency ratio
towards a sympathetic dominance in the autonomous nervous system during the
CFFT and memory tests, regardless of exposure condition. This might be
interpreted as a sign of differences in the autonomous nervous system
regulation between persons with MP related subjective symptoms and persons with
no such symptoms.
8
Mobile phone
affects cerebral blood flow in humans. J Cereb Blood Flow Metab. 26(7):885-890, 2006.
Mobile phones create a radio-frequency electromagnetic field (EMF) around them
when in use, the effects of which on brain physiology in humans are not well
known. We studied the effects of a commercial mobile phone on regional cerebral
blood flow (rCBF) in healthy humans using positron emission tomography (PET) imaging.
Positron emission tomography data was acquired using a double-blind,
counterbalanced study design with 12 male subjects performing a
computer-controlled verbal working memory task (letter 1-back). Explorative and
objective voxel-based statistical analysis revealed that a mobile phone in
operation induces a local decrease in rCBF beneath the antenna in the inferior
temporal cortex and an increase more distantly in the prefrontal cortex. Our
results provide the first evidence, suggesting that the EMF emitted by a
commercial mobile phone affects rCBF in humans. These results are consistent
with the postulation that EMF induces changes in neuronal activity.
9
Chia SE, Chia HP, Tan JS,
Prevalence of headache among handheld cellular telephone users in singapore: A
community study. Environ Health Perspect 108(11):1059-1062, 2000.
We carried out a cross-sectional community study in Singapore to determine the
prevalence of specific central nervous system (CNS) symptoms among hand-held
cellular telephone (HP) users compared to nonusers and to study the association
of risk factors and CNS symptoms among HP users. A total of 808 men and women
between 12 and 70 years of age, who lived in one community, were selected using
one-stage cluster random sampling and responses to a structured questionnaire.
The prevalence of HP users was 44.8%. Headache was the most prevalent symptom
among HP users compared to non-HP users, with an adjusted prevalence rate ratio
of 1.31 [95% confidence interval, 1.00-1.70]. There is a significant increase
in the prevalence of headache with increasing duration of usage (in minutes per
day). Prevalence of headache was reduced by more than 20% among those who used
hand-free equipment for their cellular telephones as compared to those who never
use the equipment. The use of HPs is not associated with a significant increase
of CNS symptoms other than headache.
10
Oftedal G, Wilen J, Sandstrom M, Mild KH, Symptoms
experienced in connection with mobile phone use. Occup Med (Lond)
50(4):237-245, 2000.
Many people
in Norway and Sweden reported headaches, fatigue, and other symptoms
experienced in connection with the use of a mobile phone (MP). Therefore, we
initiated a cross-sectional epidemiological study among 17,000 people, all
using an MP in their job. Thirty-one percent of the respondents in Norway and
13% of those in Sweden had experienced at least one symptom in connection with
MP use. Next to the sensations of warmth on the ear and behind/around the ear,
burning sensations in the facial skin and headaches were most commonly
reported. Most symptoms usually began during or within half an hour after the
call and lasted for up to 2 h. Relatively few had consulted a physician or been
on sick leave because of the symptoms, but about 45% among those with an MP
attributed symptom had taken steps to reduce the symptom. These results suggest
an awareness of the symptoms, but not necessarily a serious health problem.
11
Sandstrom M, Wilen J, Oftedal G, Hansson Mild K, Mobile phone use
and subjective symptoms. Comparison of symptoms experienced by users of
analogue and digital mobile phones. Occup Med (Lond) 51(1):25-35, 2001.
In 1995 many people reported symptoms such as headaches, feelings of
discomfort, warmth behind/around or on the ear and difficulties concentrating
while using mobile phones. The number of complaints was higher for people using
the digital (GSM) system, i.e. with pulse modulated fields, than for those
using the analogue (NMT) system. Our main hypothesis was that GSM users experience
more symptoms than NMT users. An epidemiological investigation was initiated
including 6379 GSM users and 5613 NMT 900 users in Sweden, and 2500 from each
category in Norway. The adjusted odds ratio did not indicate any increased risk
for symptoms for GSM users compared with NMT 900 users. Our hypothesis was
therefore disproved. However, we observed a statistically significant lower
risk for sensations of warmth on the ear for GSM users compared with NMT 900
users. The same trend was seen in Norway for sensations of warmth behind/around
the ear and in Sweden for headaches and fatigue. Factors distinguishing the two
systems (radio frequency emission, phone temperatures and various ergonomic
factors) may be responsible for these results, as well as for a secondary
finding: a statistically significant association between calling time/number of
calls per day and the prevalence of warmth behind/around or on the ear,
headaches and fatigue.
12
Santini R, Seigne M, Bonhomme-Faivre L, Bouffet S,
Defrasne E, Sage M. Symptoms experienced by users of digital cellular phones: a
pilot study in a French engineering school. Pathol Biol (Paris)
49(3):222-226, 2001.
[Article in French]
A survey study, using questionnaire, was conducted in 161 students and workers
in a French engineering school on symptoms experienced during use of digital
cellular phones. A significant increase in concentration difficult (p <
0.05) was reported by users of 1800-MHz (DCS) cellular phones compared to
900-MHz (GSM) phone users. In users of cellular phones, women significantly (p
< 0.05) complained more often of sleep disturbance than men. This sex
difference for sleep complaint is not observed between women and men non-users
of cellular phone. The use of both cellular phones and VDT significantly (p Ä
0.05) increased concentration difficulty. Digital cellular phone users also
significantly (p < 0.05) more often complained of discomfort, warmth, and
picking on the ear during phone conversation in relation with calling duration
per day and number of calls per day. The complaint warmth on the ear might be a
signal to users for stopping the call.
2. Measured Neurological effects
Measured changes in neurological behaviour.
1
Cao Z, Liu J, Li S, Zhao X. [Effects of
electromagnetic radiation from handsets of cellular telephone on
neurobehavioral function] Wei Sheng Yan Jiu 29(2):102-103, 2000.
[Article in Chinese]
In order to study the effects of electromagnetic radiation from handsets of
cellular telephone on neurobehavioral function, 81 staff with handsets of
cellular telephone and 63 staff without handsets of cellular telephone from
corporations were selected as the subjects. The subjects were investigated by
questionnaire on their general health, lifestyle habit, suppress of spirit,
handset using of cellular telephone, environmental exposure, morbidity, and the
neurobehavioral core test battery(NCTB). The data was analyzed by chi-square,
stepwise regression analysis and covariance statistics. The results showed that
the average reaction time in user's group was longer than that in control group
(P < 0.01). The time of using handset was negatively associated with
corrected reaction number (P < 0.01). The fast reaction time and the slowest
reaction time were positively associated with the length of handset using (P
< 0.01, P < 0.05). The results suggested that the handset using could
cause adverse health effects in neurobehavioral function.
2
Crouzier D, Debouzy JC, Bourbon F, Collin A, Perrin A, Testylier G. Neurophysiologic effects at low level 1.8 GHz
radiofrequency field exposure: a multiparametric approach on freely moving
rats. Pathol
Biol (Paris). 2006 Jul 31; [Epub ahead of print]
Deleterious effects on
healthcare and particularly disruption of the cholinergic system have been
reported after exposure to radiofrequency field at low power density. This work
presents a 72 hours multiparametric study, where cholinergic system was
investigated using a neurochemical, electrophysiological and physiological
approaches. Free moving rats were exposed 24 hours to RF GSM signal at 1.8 GHz
at low power density (1.2 and 9 W/m(2)). Acetylcholine (ACh) release in the
hippocampus was simultaneously monitored using the microdialysis technique,
electroencephalogram (EEG), electromyogram (EMG) and subcutaneous temperature.
A spectral analysis of EEG was also performed and sleep stages were determined.
After experimental time, the animals were sacrificed and a NMR study was
performed on lipid brain extract. No significant parameters modification was
observed under RF exposure. The only significant difference was the lack of
increase in time spent in REM sleep, the third day, for the 1.2 W/m(2) group.
This observation appeared difficult to explain and could not be reasonably
related with RF exposure. Similarly, the NMR study also failed to show any effect
of RF.
3
Curcio G, Ferrara M, De Gennaro L, Cristiani R,
D'Inzeo G, Bertini M. Time-course of electromagnetic field effects on human
performance and tympanic temperature. Neuroreport. 15(1):161-164, 2004.
The study aimed to investigate the
time-course of electromagnetic field (EMF)-induced effects on human cognitive
and behavioral performance and on tympanic temperature. Subjects were randomly
assigned to two groups, exposed to a 902.40 MHz EMF before the testing session,
or to the same signal during the data collecting session. Following a
double-blind paradigm, subjects were tested on four performance tasks: an
acoustic simple-reaction time task, a visual search task, an arithmetic
descending subtraction task and an acoustic choice-reaction time task.
Moreover, tympanic temperature was collected five times during each session.
Results indicated an improvement of both simple- and choice-reaction times and
an increase of local temperature on the exposed region under the active
exposure. There was a clear time-course of the reaction time and temperature
data, indicating that performance and physiological measures need a minimum of
25 min of EMF exposure to show appreciable changes.
4
Edelstyn N, Oldershaw A. The acute effects of
exposure to the electromagnetic field emitted by mobile phones on human
attention. Neuroreport 13(1):119-121,
2002.
The aim of our study was to investigate the effects of acute mobile phone
exposure on a range of tasks which tapped capacity and processing speed within
the attentional system. Thirty-eight healthy volunteers were randomly assigned
to either an experimental group which was exposed to a connected mobile phone
or a control group in which the mobile phone was switched off. Subjects
remained blind to mobile phone status throughout duration of study. The
experimental group were exposed to an electromagnetic field emitted by a 900
MHz mobile phone for 30 min. Cognitive performance was assessed at three points
(prior to mobile phone exposure, at 15 and 30 min post-exposure) using six
cognitive neuropsychological tests (digit span and spatial span forwards and
backwards, serial subtraction and verbal fluency). Significant differences
between the two groups were evident after 5 min on two tests of attentional
capacity (digit span forwards and spatial span backwards) and one of processing
speed (serial subtraction). In all three instances, performance was facilitated
following mobile phone exposure. No deficits were evident. These findings are
discussed in terms of possible functional and neuroanatomical bases.
5
Eliyahu I, Luria R, Hareuveny R, Margaliot M, Meiran N, Shani G.
Effects of radiofrequency radiation
emitted by cellular telephones on the cognitive functions of humans. Bioelectromagnetics.
2005 Nov 22; [Epub ahead of print]
The present study examined the effects of exposure to Electromagnetic Radiation
emitted by a standard GSM phone at 890 MHz on human cognitive functions. This
study attempted to establish a connection between the exposure of a specific
area of the brain and the cognitive functions associated with that area. A
total of 36 healthy right-handed male subjects performed four distinct
cognitive tasks: spatial item recognition, verbal item recognition, and two
spatial compatibility tasks. Tasks were chosen according to the brain side they
are assumed to activate. All subjects performed the tasks under three exposure
conditions: right side, left side, and sham exposure. The phones were
controlled by a base station simulator and operated at their full power. We
have recorded the reaction times (RTs) and accuracy of the responses. The
experiments consisted of two sections, of 1 h each, with a 5 min break in
between. The tasks and the exposure regimes were counterbalanced. The results
indicated that the exposure of the left side of the brain slows down the
left-hand response time, in the second-later-part of the experiment. This
effect was apparent in three of the four tasks, and was highly significant in only
one of the tests. The exposure intensity and its duration exceeded the common
exposure of cellular phone users.
6
Esen F, Esen H Effect of electromagnetic fields emitted by cellular phones on the
latency of evoked electrodermal activity. Int J Neurosci. 116(3):321-329, 2006.
The widespread use of cellular phones raises the question of their possible
adverse biological effects, especially on the central nervous system (CNS).
Therefore, the authors examined the effect of electromagnetic fields emitted by
cellular phones (CPEMFs) on the evoked neuronal activity of CNS relating to
generation and representation of electrodermal activity (EDA), an index of
sympathetic nervous system activity. EDA (skin resistance response; SRR)
latency was lengthened approximately 200 ms with CPEMFs exposure irrespective
of the head site next to mobile phone used. Hemispheric asymmetry of EDA-2
pathway, which is represented by shorter SRR latency in the right hand of the
right hand responders, was also distorted with CPEMFs. Because the CNS regions
including EDA-2 are also involved in tasks of motor timing and time estimation,
delayed response in this neuronal network due to CPEMFs exposure may increase
the response time of mobile phone users. Therefore, the findings point to the
potential risks of mobile phones on the function of CNS and consequently,
possible increase in the risk of phone-related driving hazards.
7
Eulitz, C, Ullsperger, P, Freude, G, Elbert ,T,
Mobile phones modulate response patterns of human brain activity. Neuroreport 9(14):3229-3232, 1998.
Mobile
phones emit a pulsed high-frequency electromagnetic field (PEMF) which may
penetrate the scalp and the skull. Increasingly, there is an interest in the
interaction of this pulsed microwave radiation with the human brain. Our
investigations show that these electromagnetic fields alter distinct aspects of
the brain's electrical response to acoustic stimuli. More precisely, our
results demonstrate that aspects of the induced but not the evoked brain
activity during PEMF exposure can be different from those not influenced by PEMF
radiation. This effect appears in higher frequency bands when subjects process
task-relevant target stimuli but was not present for irrelevant standard
stimuli. As the induced brain activity in higher frequency bands has been
proposed to be a correlate of coherent high-frequency neuronal activity, PEMF
exposure may provide means to systematically alter the pattern fluctuations in
neural mass activity.
8
Ferreri
F, Curcio
G, Pasqualetti
P, De
Gennaro L, Fini
R, Rossini
PM. Mobile phone emissions and human brain excitability. Ann Neurol. 2006 Jun 26; [Epub ahead of print]
OBJECTIVE: To test-via Transcranial Magnetic Stimulation (TMS)-the excitability
of each brain hemisphere after 'real' or 'sham' exposure to the electromagnetic
field (EMF) generated by a mobile phone operating in the Global System for
Mobile Communication (GSM). METHODS: Fifteen male volunteers attended two experimental
sessions, one week apart, in a cross-over, double-blind paradigm. In one
session the signal was turned ON (EMF-on, real exposure), in the other it was
turned OFF (EMF-off, sham exposure), for 45 minutes. Motor Evoked Potentials
(MEPs) were recorded using a paired-pulse paradigm (testing intracortical
excitability with 1 to 17 ms interstimulus intervals), both before and at
different times after exposure to the EMF. Short Intracortical Inhibition
(SICI) and Facilitation (ICF) curves were evaluated both on the exposed and
non-exposed hemispheres. Tympanic temperature was collected during each
session. RESULTS: The intracortical excitability curve becomes significantly
modified during real exposure, with SICI being reduced and ICF enhanced in the
acutely exposed brain hemisphere as compared to the contralateral, non-exposed
hemisphere or to sham exposure. Tympanic temperature showed no significant main
effect or interactions. INTERPRETATION: These results demonstrate that GSM-EMFs
modify
9
Freude, G, Ullsperger, P, Eggert ,S, Ruppe, I,
Effects of microwaves emitted by cellular phones on human slow brain
potentials. Bioelectromagnetics 19(6):384-387, 1998.
The
influence of electromagnetic fields (EMF) emitted by cellular phones on
preparatory slow brain potentials (SP) was studied in two different
experimental tasks: In the first, healthy male human subjects had to perform
simple self-paced finger movements to elicit a Bereitschaftspotential; in the
second, they performed a complex and cognitive demanding visual monitoring task
(VMT). Both tasks were performed with and without EMF exposure in
counterbalanced order. Whereas subjects' performance did not differ between the
EMF exposure conditions, SP parameters were influenced by EMF in the VMT: EMF
exposure effected a significant decrease of SPs at central and
temporo-parieto-occipital brain regions, but not at the frontal one. In the
simple finger movement task, EMF did not affect the Bereitschaftspotential.
10
Freude, G, Ullsperger, P, Eggert, S, Ruppe, I,
Microwaves emitted by cellular telephones affect human slow brain potentials. Eur
J Appl Physiol 81(1-2):18-27, 2000.
The
influence of electromagnetic fields (EMF) emitted by cellular telephones on
preparatory slow brain potentials (SP) was studied in two experiments, about 6
months apart. In the first experiment, a significant decrease of SP was found
during exposure to EMF in a complex visual monitoring task (VMT). This effect
was replicated in the second experiment. In addition to the VMT, EMF effects on
SP were analysed in two further, less demanding tasks: in a simple finger
movement task to elicit a Bereitschaftspotential (BP) and in a two-stimulus
task to elicit a contingent negative variation (CNV). In comparison to the VMT,
no significant main EMF effects were found in BP and CNV tasks. The results
accounted for a selective EMF effect on particular aspects of human information
processing, but did not indicate any influence on human performance, well-being
and health.
11
Hamblin DL, Wood AW, Croft RJ, Stough C. Examining the
effects of electromagnetic fields emitted by GSM mobile phones on human
event-related potentials and performance during an auditory task. Clin Neurophysiol. 115(1):171-178, 2004.
OBJECTIVE: Due to the widespread use of
mobile phones (MP), it is important to determine whether they affect human
physiology. The aim of this study was to explore the sensitivity of auditory
event-related potentials to electromagnetic emissions. METHODS: Twelve
participants attended two sessions, 1 week apart. Participants performed an
auditory oddball task while they were exposed to an active MP during one
session and sham exposure during the other. Each condition lasted 1 h and order
was counterbalanced. N100 and P200 latencies and amplitudes were analysed for
non-target waveforms, and N200 and P300 latencies and amplitudes were analysed
for target waveforms. RESULTS: In real relative to sham exposure N100 amplitude
and latency to non-targets were reduced, with the reduction larger over midline
and right hemisphere sites. P300 latency to targets was delayed in the real
exposure condition, however as this difference was greatest at left frontal and
left central sites the interpretation of this result is unclear. Reaction time
increased in the real relative to sham condition. No difference in accuracy was
found. CONCLUSIONS: The results suggest that MP exposure may affect neural
activity, particularly in proximity to the phone, however caution should be
applied due to the small sample size.
12
Huber R, Graf T, Cote KA, Wittmann L, Gallmann E,
Matter D, Schuderer J, Kuster N, Borbely AA, Achermann P, Exposure to
pulsed high-frequency electromagnetic field during waking affects human sleep
EEG. Neuroreport 11(15):3321-3325, 2000.
The aim of the study was to investigate whether the electromagnetic field (EMF)
emitted by digital radiotelephone handsets affects brain physiology. Healthy,
young male subjects were exposed for 30 min to EMF (900 MHz; spatial peak
specific absorption rate 1 W/kg) during the waking period preceding sleep.
Compared with the control condition with sham exposure, spectral power of the
EEG in non-rapid eye movement sleep was increased. The maximum rise occurred in
the 9.75-11.25 Hz and 12.5-13.25 Hz band during the initial part of sleep.
These changes correspond to those obtained in a previous study where EMF was
intermittently applied during sleep. Unilateral exposure induced no hemispheric
asymmetry of EEG power. The present results demonstrate that exposure during
waking modifies the EEG during subsequent sleep. Thus the changes of brain
function induced by pulsed high-frequency EMF outlast the exposure period.
13
Huber R, Treyer V, Borbély
AA, Schuderer J, Gottselig JM, Landolt H-P, Werth E,
Berthold T, Kuster N, Buck A, Achermann P, Electromagnetic
fields, such as those from mobile phones, alter regional cerebral blood flow
and sleep and waking EEG. J Sleep Res 11: 289-295, 2002.
Usage of mobile phones is rapidly increasing, but there is
limited data on the possible effects of electromagnetic field (EMF) exposure on
brain physiology. We investigated the effect of EMF vs. sham control exposure
on waking regional cerebral blood flow (rCBF) and on waking and sleep
electroencephalogram (EEG) in humans. In Experiment 1, positron emission
tomography (PET) scans were taken after unilateral head exposure to 30-min
pulse-modulated 900 MHz electromagnetic field (pm-EMF). In Experiment 2,
night-time sleep was polysomnographically recorded after EMF exposure.
Pulse-modulated EMF exposure increased relative rCBF in the dorsolateral
prefrontal cortex ipsilateral to exposure. Also, pm-EMF exposure enhanced EEG
power in the alpha frequency range prior to sleep onset and in the spindle
frequency range during stage 2 sleep. Exposure to EMF without pulse modulation
did not enhance power in the waking or sleep EEG. We previously observed EMF
effects on the sleep EEG (A. A. Borbély, R. Huber, T. Graf, B. Fuchs, E.
Gallmann and P. Achermann. Neurosci. Lett., 1999, 275: 207-210; R.
Huber, T. Graf, K. A. Cote, L. Wittmann, E. Gallmann, D. Matter, J. Schuderer,
N. Kuster, A. A. Borbély, and P. Achermann. Neuroreport, 2000, 11:
3321-3325), but the basis for these effects was unknown. The present results
show for the first time that (1) pm-EMF alters waking rCBF and (2) pulse
modulation of EMF is necessary to induce waking and sleep EEG changes.
Pulse-modulated EMF exposure may provide a new, non-invasive method for
modifying brain function for experimental, diagnostic and therapeutic purposes.
14
Huber R,
Schuderer J, Graf T, Jutz K, Borbely AA, Kuster N, Achermann P. Radio frequency
electromagnetic field exposure in humans: Estimation of SAR distribution in the
brain, effects on sleep and heart rate. Bioelectromagnetics 24(4):262-276, 2003.
In two previous studies
we demonstrated that radiofrequency electromagnetic fields (RF EMF) similar to
those emitted by digital radiotelephone handsets affect brain physiology of
healthy young subjects exposed to RF EMF (900 MHz; spatial peak specific
absorption rate [SAR] 1 W/kg) either during sleep or during the waking period
preceding sleep. In the first experiment, subjects were exposed intermittently
during an 8 h nighttime sleep episode and in the second experiment,
unilaterally for 30 min prior to a 3 h daytime sleep episode. Here we report an
extended analysis of the two studies as well as the detailed dosimetry of the
brain areas, including the assessment of the exposure variability and
uncertainties. The latter enabled a more in depth analysis and discussion of
the findings. Compared to the control condition with sham exposure, spectral
power of the non-rapid eye movement sleep electroencephalogram (EEG) was
initially increased in the 9-14 Hz range in both experiments. No topographical
differences with respect to the effect of RF EMF exposure were observed in the
two experiments. Even unilateral exposure during waking induced a similar
effect in both hemispheres. Exposure during sleep reduced waking after sleep
onset and affected heart rate variability. Exposure prior to sleep reduced
heart rate during waking and stage 1 sleep. The lack of asymmetries in the
effects on sleep EEG, independent of bi- or unilateral exposure of the cortex,
may indicate involvement of subcortical bilateral projections to the cortex in
the generation of brain function changes, especially since the exposure of the
thalamus was similar in both experiments (approx. 0.1 W/kg).
15
Huber R,
Treyer V, Schuderer J, Berthold T, Buck A, Kuster N, Landolt HP, Achermann P. Exposure to
pulse-modulated radio frequency electromagnetic fields affects regional
cerebral blood flow. Eur
J Neurosci.
21(4):1000-1006, 2005.
We investigated the effects of radio frequency electromagnetic fields (RF EMF)
similar to those emitted by mobile phones on waking regional cerebral blood
flow (rCBF) in 12 healthy young men. Two types of RF EMF exposure were applied:
a 'base-station-like' and a 'handset-like' signal. Positron emission tomography
scans were taken after 30 min unilateral head exposure to pulse-modulated 900
MHz RF EMF (10 g tissue-averaged spatial peak-specific absorption rate of 1
W/kg for both conditions) and sham control. We observed an increase in relative
rCBF in the dorsolateral prefrontal cortex on the side of exposure. The effect
depended on the spectral power in the amplitude modulation of the RF carrier
such that only 'handset-like' RF EMF exposure with its stronger low-frequency
components but not the 'base-station-like' RF EMF exposure affected rCBF. This
finding supports our previous observation that pulse modulation of RF EMF is
necessary to induce changes in the waking and sleep EEG, and substantiates the
notion that pulse modulation is crucial for RF EMF-induced alterations in brain
physiology.
16
Jech R, Sonka
K, Ruzicka E, Nebuzelsky A, Bohm J, Juklickova M, Nevsimalova S. Electromagnetic
field of mobile phones affects visual event related potential in patients with
narcolepsy. Bioelectromagnetics 22(7):519-528, 2001.
The effects of the mobile phone (MP)
electromagnetic fields on electroencephalography (EEG) and event-related
potentials (ERP) were examined. With regard to the reported effects of MP on
sleep, 22 patients with narcolepsy-cataplexy were exposed or sham exposed for
45 min to the MP (900 MHz, specific absorption rate 0.06 W/kg) placed close to
the right ear in a double blind study. There were no changes of the EEG
recorded after the MP exposure. A subgroup of 17 patients was studied on visual
ERP recorded during the MP exposure. Using an adapted "odd-ball"
paradigm, each patient was instructed to strike a key whenever rare target
stimuli were presented. There were three variants of target stimuli (horizontal
stripes in (i) left, (ii) right hemifields or (iii) whole field of the screen).
The exposure enhanced the positivity of the ERP endogenous complex solely in
response to target stimuli in the right hemifield of the screen (P < 0.01).
The reaction time was shortened by 20 ms in response to all target stimuli (P
< 0.05). In conclusion, the electromagnetic field of MP may suppress the
excessive sleepiness and improve performance while solving a monotonous
cognitive task requiring sustained attention and vigilance.
17
Keetley V, Wood AW, Spong J, Stough C. Neuropsychological
sequelae of digital mobile phone exposure in humans. Neuropsychologia.
2006 Apr 14; [Epub ahead of print]
The effect of electromagnetic fields from digital mobile phones (DMP) on
cognitive functioning is an area receiving increased attention. This study compares
the performance of 120 volunteers on 8 neuropsychological tests during real or
sham exposure to a DMP set to maximum permissible radiofrequency power output.
When results were adjusted for known covariates (gender, age, or education),
several alterations at significance levels of p<0.05 were obtained. Of
these, simple and choice reaction times (CRT) showed strong evidence of
impairment. Further, performance on the Trail Making Task (TMT) improved,
supporting the hypothesis that DMP radiofrequency emissions improve the speed
of processing of information held in working memory.
18
Koivisto, M, Revonsuo, A, Krause, C, Haarala, C,
Sillanmaki, L, Laine, M, Hamalainen, H, Effects of 902 MHz electromagnetic
field emitted by cellular telephones on response times in humans. Neuroreport
11(2):413-415, 2000.
The present study
examined possible influences of a 902 MHz electromagnetic field emitted by
cellular telephones on cognitive functioning in 48 healthy humans. A battery of
12 reaction time tasks was performed twice by each participant in a
counterbalanced order: once with and once without the exposure to the field.
The results showed that the exposure to the electromagnetic field speeded up
response times in simple reaction time and vigilance tasks and that the
cognitive time needed in a mental arithmetics task was decreased. The results
suggest that exposure to the electromagnetic field emitted by cellular
telephones may have a facilitatory effect on brain functioning, especially in
tasks requiring attention and manipulation of information in working memory.
19
Koivisto M, Krause CM, Revonsuo A, Laine M,
Hamalainen H, The effects of electromagnetic field emitted by GSM phones on
working memory. Neuroreport
11(8):1641-1643, 2000.
The influence of pulsed radiofrequency (RF) electromagnetic fields of
digital GSM mobile phones on working memory in healthy subjects were studied.
Memory load was varied from 0 to 3 items in an n-back task. Each subject was
tested twice within a single session, with and without the RF exposure (902MHz,
217Hz). The RF field speeded up response times when the memory load was three
items but no effects of RF were observed with lower loads. The results suggest
that RF fields have a measurable effect on human cognitive performance and
encourage further studies on the interactions of RF fields with brain function.
20
Kramarenko AV, Tan U. EFFECTS OF
HIGH-FREQUENCY ELECTROMAGNETIC FIELDS ON HUMAN EEG: A BRAIN MAPPING STUDY. Int J Neurosci. 113(7):1007-1019, 2003.
Cell phones emitting pulsed high-frequency electromagnetic fields (EMF) may
affect the human brain, but there are inconsistent results concerning their
effects on electroencephalogram (EEG). We used a 16-channel telemetric
electroencephalograph (ExpertTM), to record EEG changes during exposure of
human skull to EMF emitted by a mobile phone. Spatial distribution of EMF was
especially concentrated around the ipsilateral eye adjacent to the basal
surface of the brain. Traditional EEG was full of noises during operation of a
cellular phone. Using a telemetric electroencephalograph (ExpertTM) in awake
subjects, all the noise was eliminated, and EEG showed interesting changes:
after a period of 10-15 s there was no visible change, the spectrum median
frequency increased in areas close to antenna; after 20-40 s, a slow-wave
activity (2.5-6.0 Hz) appeared in the contralateral frontal and temporal areas.
These slow waves lasting for about one second repeated every 15-20 s at the
same recording electrodes. After turning off the mobile phone, slow-wave
activity progressively disappeared; local changes such as increased median
frequency decreased and disappeared after 15-20 min. We observed similar
changes in children, but the slow-waves with higher amplitude appeared earlier
in children (10-20 s) than adults, and their frequency was lower (1.0-2.5 Hz)
with longer duration and shorter intervals. The results suggested that cellular
phones may reversibly influence the human brain, inducing abnormal slow waves
in EEG of awake persons.
21
Krause CM, Sillanmaki L, Koivisto M, Haggqvist A,
Saarela C, Revonsuo A, Laine M, Hamalainen H, Effects of electromagnetic field
emitted by cellular phones on the EEG during a memory task. Neuroreport
11(4):761-764, 2000.
The effects of
electromagnetic fields (EMF) emitted by cellular phones on the ERD/ERS of the
4-6 Hz, 6-8 Hz, 8-10 Hz and 10-12 Hz EEG frequency bands were studied in 16
normal subjects performing an auditory memory task. All subjects performed the
memory task both with and without exposure to a digital 902 MHz EMF in
counterbalanced order. The exposure to EMF significantly increased EEG power in
the 8-10 Hz frequency band only. Nonetheless, the presence of EMF altered the
ERD/ERS responses in all studied frequency bands as a function of time and
memory task (encoding vs retrieval). Our results suggest that the exposure to
EMF does not alter the resting EEG per se but modifies the brain responses
significantly during a memory task.
22
Krause CM, Sillanmaki L,
Koivisto M, Haggqvist A, Saarela C, Revonsuo A, Laine M, Hamalainen H, Effects
of electromagnetic fields emitted by cellular phones on the
electroencephalogram during a visual working memory task. Int J Radiat Biol
76(12):1659-1667, 2000.
PURPOSE: To examine the effects of electromagnetic fields (EMF) emitted by
cellular phones on the event-related desynchronization/synchronization
(ERD/ERS) responses of the 4-6, 6-8, 8-10 and 10-12Hz EEG frequency bands
during cognitive processing. MATERIALS AND METHODS: Twenty-four subjects
performed a visual sequential letter task (n-back task) with three different
working memory load conditions: zero, one and two items. All subjects performed
the memory task both with and without exposure to a digital 902 MHz EMF in
counterbalanced order. RESULTS: The presence of EMF altered the ERD/ERS
responses in the 6-8 and 8-10 Hz frequency bands but only when examined as a
function of memory load and depending also on whether the presented stimulus
was a target or not. CONCLUSIONS: The results suggest that the exposure to EMF
modulates the responses of EEG oscillatory activity approximately 8 Hz
specifically during cognitive processes.
23
Purpose: To assess the
effects of electromagnetic fields (EMF) emitted by mobile phones (MP) on the 1
- 20 Hz event-related brain oscillatory EEG (electroencephalogram) responses in
children performing an auditory memory task (encoding and
recognition).Materials and methods: EEG data were gathered while 15 subjects
(age 10 - 14 years) performed an auditory memory task both with and without
exposure to a digital 902 MHz MP in counterbalanced order.Results: During
memory encoding, the active MP modulated the event-related
desynchronization/synchronization (ERD/ERS) responses in the approximately 4 -
8 Hz EEG frequencies. During recognition, the active MP transformed these brain
oscillatory responses in the approximately 4 - 8 Hz and approximately 15 Hz
frequencies.Conclusions: The current findings suggest that EMF emitted by
mobile phones has effects on brain oscillatory responses during cognitive
processing in children.
24
Lebedeva NN, Sulimov AV, Sulimova OP, Kotrovskaya TI,
Gailus T,
Cellular phone electromagnetic field effects on bioelectric activity of human
brain. Crit Rev Biomed Eng 28(1-2):323-337, 2000.
24 volunteers participated in the experiments. The investigation of EEG
reactions to cellular phone (EMF frequency 902.4 MHz and intensity 0.06 mW/cm2)
was conducted. Two experiments were performed with each subject--cellular phone
exposure and Placebo Duration of the experiment was 60 min: 15 min--background;
15 min--EMF exposure or Placebo; 30 min--afterexposure. EEG was recorded in 16
standard leads with "eyes open" and "eyes closed". Special
software with non-linear dynamics was developed for EEG analyses. One
parameter, multichannel (global) correlation dimension, was calculated. The
changes of these parameters can be evidence of brain functional state changes.
As a result of EEG record processing, a significant increase of global
correlation dimension during the exposure and afterexposure period was
discovered, more pronounced in the case of "eyes closed". That can be
viewed as the manifestation of cortex activation under phone EMF exposure.
25
Lebedeva NN, Sulimov AV, Sulimova OP, Korotkovskaya
TI, Gailus T, Investigation of brain potentials in sleeping humans exposed
to the electromagnetic field of mobile phones. Crit Rev Biomed Eng 29(1):125-133, 2001.
An investigation was made of 8-hour EEG tracings of sleeping humans exposed to
the electromagnetic field of a GSM-standard mobile phone. To analyze the
EEG-patterns, manual scoring, nonlinear dynamics, and spectral analysis were
employed. It was found that, when human beings were exposed to the
electromagnetic field of a cellular phone, their cerebral cortex biopotentials
revealed an increase in the alpha-range power density as compared to the
placebo experiment. It was also found that the dimension of EEG correlation
dynamics and the relation of sleep stages changed under the influence of the
electromagnetic field of a mobile phone.
26
Lee TMC, Ho SMY,
Tsang LYH, Yang SYC, Li LSW,
Chan CCH, Effect on human attention of exposure to the
electromagnetic field emitted by mobile phones. NeuroReport 12:729-731,
2001.
This study
examined the effect of exposure to the electromagnetic field emitted by mobile
phones on human attention. Three measures of attention were administered to 72
teenagers, 37 of whom were mobile phone users. The results showed that the
mobile phone users performed better on one of the three measures of attention
than did the non-mobile phone users. The results suggest that exposure to the
electro- magnetic field emitted by mobile phones may have a mild facilitating
effect on attention functions, which is consistent with previous observations
that exposure to the electromagnetic field has a facilitating effect on
cognitive processing. The possibility that mobile phone users may be naturally
better at multiple tasking tasks was discussed.
27
Lee TM, Lam PK, Yee LT, Chan CC. The effect of
the duration of exposure to the electromagnetic field emitted by mobile phones
on human attention. Neuroreport. 14(10):1361-1364, 2003.
Previous findings suggested the facilitating effect of the electromagnetic
field emitted by mobile phones on human attention. This study aimed to examine
the relationship between the facilitating effect and the duration of exposure
to the electromagnetic field emitted by mobile phones on human attention.
Seventy-eight university students were randomly assigned to either an experimental
or a control group. Their performance in the administered attention tasks was
compared. Participants in the experimental group performed better on one of the
two measures of attention only after they had been exposed to the
electromagnetic field emitted by the mobile phone for some time. The results
seem to suggest that attention functions may be differentially enhanced after
exposing to the electromagnetic field emitted by mobile phones. Furthermore,
this transient facilitation effect might be dose dependent.
28
Litovitz TA, Krause D, Penafiel M, Elson EC, Mullins
JM, The role of coherence time in the effect of microwaves on ornithine
decarboxylase activity. Bioelectromagnetics 14(5):395-403, 1993.
Previously, we demonstrated the requirements for a minimum coherence time of an
applied, small amplitude (10 microT) ELF magnetic field if the field were to
produce an enhancement of ornithine decarboxylase activity in L929 fibroblasts.
Further investigation has revealed a remarkably similar coherence time
phenomenon for enhancement of ornithine decarboxylase activity by
amplitude-modulated 915 MHz microwaves of large amplitude (SAR 2.5 W/kg).
Microwave fields modulated at 55, 60, or 65 Hz approximately doubled ornithine
decarboxylase activity after 8 h. Switching modulation frequencies from 55 to
65 Hz at coherence times of 1.0 s or less abolished enhancement, while times of
10 s or longer provided full enhancement. Our results show that the microwave
coherence effects are remarkably similar to those observed with ELF fields.
29
Litovitz, TA, Penafiel, LM, Farrel, JM, Krause, D,
Meister, R, Mullins, JM Bioeffects induced by exposure to microwaves are
mitigated by superposition of ELF noise. Bioelectromagnetics
18(6):422-430, 1997.
We have
previously demonstrated that microwave fields, amplitude modulated (AM) by an
extremely low-frequency (ELF) sine wave, can induce a nearly twofold
enhancement in the activity of ornithine decarboxylase (ODC) in L929 cells at
SAR levels of the order of 2.5 W/kg. Similar, although less pronounced, effects
were also observed from exposure to a typical digital cellular phone test
signal of the same power level, burst modulated at 50 Hz. We have also shown
that ODC enhancement in L929 cells produced by exposure to ELF fields can be
inhibited by superposition of ELF noise. In the present study, we explore the
possibility that similar inhibition techniques can be used to suppress the
microwave response. We concurrently exposed L929 cells to 60 Hz AM microwave
fields or a 50 Hz burst-modulated DAMPS (Digital Advanced Mobile Phone System)
digital cellular phone field at levels known to produce ODC enhancement,
together with band-limited 30-100 Hz ELF noise with root mean square amplitude
of up to 10 microT. All exposures were carried out for 8 h, which was
previously found to yield the peak microwave response. In both cases, the ODC
enhancement was found to decrease exponentially as a function of the noise root
mean square amplitude. With 60 Hz AM microwaves, complete inhibition was
obtained with noise levels at or above 2 microT. With the DAMPS digital
cellular phone signal, complete inhibition occurred with noise levels at or
above 5 microT. These results suggest a possible practical means to inhibit
biological effects from exposure to both ELF and microwave fields.
30
Lopez-Martin E, Relova-Quinteiro JL, Gallego-Gomez R, Peleteiro-Fernandez M, Jorge-Barreiro FJ, Ares-Pena FJ. GSM radiation triggers seizures and increases cerebral c-Fos positivity
in rats pretreated with subconvulsive doses of picrotoxin. Neurosci Lett. 2006 Jan 27; [Epub ahead of
print]
This study investigated the effects of mobile-phone-type radiation on the
cerebral activity of seizure-prone animals. When rats transformed into an
experimental model of seizure-proneness by acute subconvulsive doses of
picrotoxin were exposed to 2h GSM-modulated 900MHz radiation at an intensity
similar to that emitted by mobile phones, they suffered seizures and the levels
of the neuronal activity marker c-Fos in neocortex, paleocortex, hippocampus
and thalamus increased markedly. Non-irradiated picrotoxin-treated rats did not
suffer seizures, and their cerebral c-Fos counts were significantly lower.
Radiation caused no such differences in rats that had not been pretreated with
picrotoxin. We conclude that GSM-type radiation can induce seizures in rats
following their facilitation by subconvulsive doses of picrotoxin, and that
research should be pursued into the possibility that this kind of radiation may
similarly affect brain function in human subjects with epileptic disorders.
31
Loughran SP, Wood AW, Barton JM, Croft RJ, Thompson B, Stough C. The effect
of electromagnetic fields emitted by mobile phones on human sleep. Neuroreport. 16(17):1973-1976, 2005.
Previous research
has suggested that exposure to radiofrequency electromagnetic fields increases
electroencephalogram spectral power in non-rapid eye movement sleep. Other
sleep parameters have also been affected following exposure. We examined
whether aspects of sleep architecture show sensitivity to electromagnetic
fields emitted by digital mobile phone handsets. Fifty participants were
exposed to electromagnetic fields for 30 min prior to sleep. Results showed a
decrease in rapid eye movement sleep latency and increased electroencephalogram
spectral power in the 11.5-12.25 Hz frequency range during the initial part of
sleep following exposure. These results are evidence that mobile phone exposure
prior to sleep may promote rapid eye movement sleep and modify the sleep
electroencephalogram in the first non-rapid eye movement sleep period.
32
Maby E, Jeannes RL, Faucon
G, Liegeois-Chauvel C, De Seze R. Effects of GSM signals on auditory evoked
responses. Bioelectromagnetics. 2005 May 10; [Epub ahead of
print]
The article presents a study of the influence of radio frequency (RF) fields
emitted by mobile phones on human cerebral activity. Our work was based on the
study of Auditory Evoked Potentials (AEPs) recorded on the scalp of healthy
humans and epileptic patients. The protocol allowed us to compare AEPs recorded
with or without exposure to RFs. To get a reference, a control session was also
introduced. In this study, the correlation coefficients computed between AEPs,
as well as the correlation coefficients between spectra of AEPs were
investigated to detect a possible difference due to RFs. A difference in the
correlation coefficients computed in control and experimental sessions was
observed, but it was difficult to deduce the effect of RFs on human health.
33
Maby E, Jeannes Rle B, Faucon G. Scalp localization of human auditory cortical
activity modified by GSM electromagnetic fields. Int J
Radiat Biol. 82(7):465-472, 2006.
Purpose: This study attempted
to determine whether there is a localized effect of GSM (Global System for
Mobile communications) microwaves by studying the Auditory Evoked Potentials
(AEP) recorded at the scalp of nine healthy subjects and six epileptic
patients.Materials and methods: We determined the influence of GSM
RadioFrequency (RF) on parameters characterizing the AEP in time or/and
frequency domains. A parameter selection method using SVM (Support Vector
Machines)-based criteria allowed us to estimate those most altered by the
radiofrequencies. The topography of the parameter modifications was computed to
determine the localization of the radiofrequency influence. A statistical test
was conducted for selected scalp areas, in order to determine whether there
were significant localized alterations due to the RF.Results: The epileptic
patients showed a lengthening of the scalp component N100 (100 ms latency) in
the frontal area contralateral to the radiation, which may be due to an
afferent tract alteration. For the healthy subjects, an amplitude increase of
the P200 wave (200 ms latency) was identified in the frontal area.Conclusions:
The present study suggests that radiofrequency fields emitted by mobile phones
modify the AEP. Nevertheless, no direct link between these findings and
RF-induced damages in brain function was established.
34
Maier R, Greter SE, Maier N. Effects of
pulsed electromagnetic fields on cognitive processes - a pilot study on pulsed
field interference with cognitive regeneration. Acta Neurol Scand. 110(1):46-52, 2004.
BACKGROUND: Due to the ubiquitous use of cellular phones much has been
speculated on secondary effects of electromagnetic irradiation emitted by
those. Additionally, several studies have reported vegetative alterations as
well as effects on the neuronal and molecular levels in humans. Here, using a
psycho-physiological test paradigm, we examined effects of exposure to pulsed
electromagnetic fields on cognitive performance. MATERIALS AND METHODS: In 11
volunteers, we tested cognitive processing under field exposure (GSM standard)
and under field-free conditions. To examine the hypothesized effect of pulsed
fields, we applied an auditory discrimination task and determined the
participant's current 'Order Threshold' value. Following a first test cycle,
the volunteers had to relax for 50 min while being, or not, exposed to pulsed
electromagnetic fields. Subsequently, the test was repeated. Data acquired
before and after the resting phase were compared from both experimental
conditions. RESULTS: We found that nine of the 11 test participants (81.8%)
showed worse results in their auditory discrimination performance upon field
exposure as compared with control conditions. Group data comparison revealed a
statistical significance of P = 0.0105. CONCLUSION: We could show that the
participants' cognitive performance was impaired after exposure to pulsed
electromagnetic fields. With regard to this finding, we recommend that the use of cellular phones
should be restricted generally and in particular in respect of physical hazard
of high-risk groups, e.g. elderly, children and ill people.
35
Mann, K, Roschke, J,
Effects of pulsed high-frequency electromagnetic fields on human sleep. Neuropsychobiology 33(1):41-47, 1996.
In the present
study we investigated the influence of pulsed high-frequency electromagnetic
fields of digital mobile radio telephones on sleep in healthy humans. Besides a
hypnotic effect with shortening of sleep onset latency, a REM suppressive
effect with reduction of duration and percentage of REM sleep was found.
Moreover, spectral analysis revealed qualitative alterations of the EEG signal
during REM sleep with an increased spectral power density. Knowing the
relevance of REM sleep for adequate information processing in the brain,
especially concerning mnestic functions and learning processes, the results
emphasize the necessity to carry out further investigations on the interaction
of this type of electromagnetic fields and the human organism.
36
Mann, K, Wagner, P, Brunn, G, Hassan, F, Hiemke, C,
Roschke, J, Effects of pulsed high-frequency electromagnetic fields on the
neuroendocrine system. Neuroendocrinology 67(2):139-144, 1998.
The
influence of pulsed high-frequency electromagnetic fields emitted from a
circularly polarized antenna on the neuroendocrine system in healthy humans was
investigated (900 MHz electromagnetic field, pulsed with 217 Hz, average power
density 0.02 mW/cm2). Nocturnal hormone profiles of growth hormone (GH),
cortisol, luteinizing hormone (LH) and melatonin were determined under
polysomnographic control. An alteration in the hypothalamo-pituitary-adrenal
axis activity was found with a slight, transient elevation in the cortisol
serum level immediately after onset of field exposure which persisted for 1 h.
For GH, LH and melatonin, no significant effects were found under exposure to
the field compared to the placebo condition, regarding both total hormone
production during the entire night and dynamic characteristics of the secretion
pattern. Also the evaluation of the sleep EEG data revealed no significant
alterations under field exposure, although there was a trend to an REM
suppressive effect. The results indicate that weak high-frequency
electromagnetic fields have no effects on nocturnal hormone secretion except
for a slight elevation in cortisol production which is transient, pointing to
an adaptation of the organism to the stimulus.
37
Papageorgiou
CC, Nanou ED, Tsiafakis VG, Capsalis CN, Rabavilas AD. Gender related
differences on the EEG during a simulated mobile phone signal. Neuroreport. 15(16):2557-2560, 2004.
The present study
investigated the gender-related influence of electromagnetic fields (EMF),
similar to that emitted by mobile phones, on brain activity. Ten women and nine
men performed a short memory task (Wechsler test), both without (baseline) and
with exposure to a 900 MHz signal. The EEG energy of the total waveform and the
alpha, beta, delta and theta; rhythms were calculated from the recordings of 15
scalp electrodes. Baseline EEG energy of males was greater than that of
females, while exposure to EMF decreased EEG energy of males and increased that
of females. Memory performance was invariant to EMF exposure and gender
influences. These findings indicate that EMF may exert a gender-related
nfluence on brain activity.
38
Preece, AW, Iwi, G, Davies-Smith, A, Wesnes, K,
Butler, S, Lim, E, Varey, A, Effect of a 915-MHz simulated mobile phone signal
on cognitive function in man. Int J Radiat Biol 75(4):447-456, 1999.
PURPOSE: To
examine whether a simulated mobile telephone transmission at 915 MHz has an
effect on cognitive function in man. MATERIALS AND METHODS: Thirty-six subjects
in two groups were each given two training sessions and then three test sessions
in a randomized three-way cross-over design. About 1 W mean power at 915 MHz
from a quarter-wave antenna mounted on a physical copy of an analogue phone, as
a sine wave, or modulated at 217 Hz with 12.5% duty cycle, or no power, was
applied to the left squamous temple region of the subjects while they undertook
a series of cognitive function tests lasting approximately 25-30 min. The
second group was investigated for sleep, consumption of alcohol and beverages,
and any other substances that might affect performance. RESULTS: In both
groups, the only test affected was the choice reaction time and this showed as
an increase in speed (a decrease in reaction time). There were no changes in
word, number or picture recall, or in spatial memory. While an effect of
visit-order was evident suggesting a learning effect of repeat tests, the
design of the study allowed for this. Additionally, there was no systematic
error introduced as a result of consumption of substances or sleep time.
CONCLUSIONS: There was evidence of an increase in responsiveness, strongly in
the analogue and less in the digital simulation, in choice reaction time. This
could be associated with an effect on the angular gyrus that acts as an
interface between the visual and speech centres and which lies directly under
and on the same side as the antenna. Such an effect could be consistent with
mild localized heating, or possibly a non-thermal response, which is
nevertheless power-dependent.
39
Smythe JW, Costall B. Mobile phone use
facilitates memory in male, but not female, subjects. Neuroreport 14(2):243-246, 2003.
In the present study we report on the effects of mobile phone exposure on
short- and long-term memory in male and female subjects. Subjects were
university undergraduate students, and consisted of right-handed, males ( = 33)
and females ( = 29). Individuals were randomly assigned to one of three
experimental conditions: no phone exposure; inactive phone exposure; and active
phone exposure. They were provided with a series of words to learn, structured
in a two-dimensional shape, and given 3 min to memorise the words. After a 12
min distraction task, they were then asked to draw the shape (spatial) and
place the correct words (semantic) into the appropriate boxes. One week later
the same subjects were brought back to again redraw the shape and words. Error
scores were determined and analysed by non-parametric techniques. The results
show that males exposed to an active phone made fewer spatial errors than those
exposed to an active phone condition, while females were largely unaffected.
These results further indicate that mobile phone exposure has functional
consequences for human subjects, and these effects appear to be sex-dependent.
40
Vecchio F, Babiloni C, Ferreri F, Curcio G, Fini R, Del Percio C, Rossini PM. Mobile phone emission modulates
interhemispheric functional coupling of EEG alpha rhythms. Eur J
Neurosci. 25(6):1908-1913, 2007.
We tested the working
hypothesis that electromagnetic fields from mobile phones (EMFs) affect
interhemispheric synchronization of cerebral rhythms, an important
physiological feature of information transfer into the brain. Ten subjects
underwent two electroencephalographic (EEG) recordings, separated by 1 week,
following a crossover double-blind paradigm in which they were exposed to a
mobile phone signal (global system for mobile communications; GSM). The mobile
phone was held on the left side of the subject head by a modified helmet, and
orientated in the normal position for use over the ear. The microphone was
orientated towards the corner of the mouth, and the antenna was near the head
in the parietotemporal area. In addition, we positioned another similar phone
(but without battery) on the right side of the helmet, to balance the weight
and to prevent the subject localizing the side of GSM stimulation (and
consequently lateralizing attention). In one session the exposure was real
(GSM) while in the other it was Sham; both sessions lasted 45 min. Functional
interhemispheric connectivity was modelled using the analysis of EEG spectral
coherence between frontal, central and parietal electrode pairs. Individual EEG
rhythms of interest were delta (about 2-4 Hz), theta (about 4-6 Hz), alpha 1
(about 6-8 Hz), alpha 2 (about 8-10 Hz) and alpha 3 (about 10-12 Hz). Results
showed that, compared to Sham stimulation, GSM stimulation modulated the
interhemispheric frontal and temporal coherence at alpha 2 and alpha 3 bands.
The present results suggest that prolonged mobile phone emission affects not
only the cortical activity but also the spread of neural synchronization
conveyed by interhemispherical functional coupling of EEG rhythms.
41
Von Klitzing, L, Low-frequency pulsed electromagnetic
fields influence EEG of man. Phys. Medica
11:77-80, 1995.
New techniques
using low-frequency puled electromagnetic fields (e.g., digital
telecommunication) have raised the question for interference with the
biological system of man. EEG data of
man sampled under the influence of these electromagnetic fields are altered
extremely in the range of alpha-activity as well as during after exposure for
some hours. The biological effect is induced by field intensities lower than
the given international limiting values.
3. Neurological Function
Measured changes in brain chemistry and neurological
function.
1
Bolshakov MA, Alekseev SI, Bursting responses of
Lymnea neurons to microwave radiation. Bioelectromagnetics
13(2):119-129, 1992.
Microelectrode and voltage-clamp techniques were modified to record spontaneous
electrical activity and ionic currents of Lymnea stagnalis neurons during
exposure to a 900-MHz field in a waveguide-based apparatus. The field was
pulse-modulated at repetition rates ranging from 0.5 to 110 pps, or it was
applied as a continuous wave (CW). When subjected to pulsed waves (PW), rapid,
burst-like changes in the firing rate of neurons occurred at SARs of a few W/kg.
If the burst-like irregularity was present in the firing rate under control
conditions, irradiation enhanced its probability of occurrence. The effect was
dependent on modulation, but not on modulation frequency, and it had a
threshold SAR near 0.5 W/kg. CW radiation had no effect on the firing rate
pattern at the same SAR. Mediator-induced, current activation of acetylcholine,
dopamine, serotonin, or gamma-aminobutyric-acid receptors of the neuronal soma
was not altered during CW or PW exposures and, hence, could not have been
responsible for the bursting effect.
2
Borbely, AA, Huber, R, Graf, T, Fuchs, B, Gallmann,
E, Achermann, P, Pulsed high-frequency electromagnetic field affects human
sleep and sleep electroencephalogram. Neurosci Lett 275(3):207-210, 1999.
To investigate whether the electromagnetic field
(EMF) emitted by digital radiotelephone handsets affects the brain, healthy,
young subjects were exposed during an entire night-time sleep episode to an
intermittent radiation schedule (900 MHz; maximum specific absorption rate 1
W/kg) consisting of alternating 15-min on-15-min off intervals. Compared with a
control night with sham exposure, the amount of waking after sleep onset was
reduced from 18 to 12 min. Spectral power of the electroencephalogram in
non-rapid eye movement sleep was increased. The maximum rise occurred in the
10-11 Hz and 13.5-14 Hz bands during the initial part of sleep and then
subsided. The results demonstrate that pulsed high-frequency EMF in the range
of radiotelephones may promote sleep and modify the sleep EEG.
3
Croft R,
Chandler J, Burgess A, Barry R, Williams J, Clarke A. Acute mobile
phone operation affects neural function in humans. Clin Neurophysiol 113(10):1623, 2002.
OBJECTIVES: Mobile phones (MP) are used extensively and yet little is known
about the effects they may have on human physiology. There have been
conflicting reports regarding the relation between MP use and the
electroencephalogram (EEG). The present study suggests that this conflict may
be due to methodological differences such as exposure durations, and tests
whether exposure to an active MP affects EEG as a function of time.METHODS:
Twenty-four subjects participated in a single-blind fully counterbalanced
cross-over design, where both resting EEG and phase-locked neural responses to
auditory stimuli were measured while a MP was either operating or turned
off.RESULTS: MP exposure altered resting EEG, decreasing 1-4Hz activity (right
hemisphere sites), and increasing 8-12Hz activity as a function of exposure
duration (midline posterior sites). MP exposure also altered early phase-locked
neural responses, attenuating the normal response decrement over time in the
4-8Hz band, decreasing the response in the 1230Hz band globally and as a
function of time, and increasing midline frontal and lateral posterior
responses in the 30-45Hz band.CONCLUSIONS: Active MPs affect neural function in
humans and do so as a function of exposure duration. The temporal nature of this effect may contribute
to the lack of consistent results reported in the literature.
4
Curcio G, Ferrara M, Moroni F, D'Inzeo G, Bertini M, De Gennaro L.
Is the brain influenced by a phone
call? An EEG study of resting wakefulness. Neurosci Res. 2005 Aug 12;
[Epub ahead of print]
We recorded the resting electroencephalogram of 20 healthy subjects in order to
investigate the effect of electromagnetic field (EMF) exposure on EEG waking
activity and its temporal development. The subjects were randomly assigned to
two groups and exposed, in double-blind conditions, to a typical mobile phone
signal (902.40MHz, modulated at 217Hz, with an average power of 0.25W) before
or during the EEG recording session. The results show that, under real exposure
as compared to baseline and sham conditions, EEG spectral power was influenced
in some bins of the alpha band. This effect was greater when the EMF was on
during the EEG recording session than before it. The present data lend further
support to the idea that pulsed high-frequency electromagnetic fields can
affect normal brain functioning, also if no conclusions can be drawn about the
possible health effects.
5
D'Costa H, Trueman G, Tang L, Abdel-rahman U,
Abdel-rahman W, Ong K, Cosic I. Human brain wave activity
during exposure to radiofrequency field emissions from mobile phones. Australas
Phys Eng Sci Med. 26(4):162-167, 2003.
The aim of this study was to determine whether there is an effect of mobile
phone electromagnetic field emissions on the human electroencephalograph (EEG).
EEG recordings from ten awake subjects were taken during exposure to
radiofrequency (RF) emissions from a mobile phone positioned behind the head.
Two experimental trials were conducted. In the first trial, RF exposures were
generated by a GSM mobile phone with the speaker disabled and configured to transmit
at full-radiated power. During the second trial, exposures were generated by a
non-modified GSM mobile phone in active standby mode. For each trial, subjects
were exposed in five minute intervals to a randomized, interrupted sequence of
five active and five sham exposures. The experiment was conducted under
single-blind conditions. The average EEG band power in active exposure
recordings was compared to corresponding sham recordings. Statistical tests
indicated significant difference in the full-power mode trial within the EEG
alpha (8-13 Hz) and beta (13-32 Hz) bands. A subsequent statistical analysis of
median spectral power in discrete EEG rhythms revealed significant differences
in 7 of the 32 distinct frequencies overall. In conclusion, the results of this
study lend support to EEG effects from mobile phones activated in talk-mode.
6
Ilhan A, Gurel A, Armutcu F, Kamisli S, Iraz M, Akyol
O, Ozen S. Ginkgo biloba prevents mobile phone-induced oxidative stress
in rat brain. Clin
Chim Acta. 340(1-2): 153-162, 2004.
BACKGROUND: The widespread use of mobile phones (MP) in recent years has raised
the research activities in many countries to determine the consequences of
exposure to the low-intensity electromagnetic radiation (EMR) of mobile phones.
Since several experimental studies suggest a role of reactive oxygen species
(ROS) in EMR-induced oxidative damage in tissues, in this study, we
investigated the effect of Ginkgo biloba (Gb) on MP-induced oxidative damage in
brain tissue of rats. METHODS: Rats (EMR+) were exposed to 900 MHz EMR from MP
for 7 days (1 h/day). In the EMR+Gb groups, rats were exposed to EMR and
pretreated with Gb. Control and Gb-administrated groups were produced by
turning off the mobile phone while the animals were in the same exposure
conditions. Subsequently, oxidative stress markers and pathological changes in
brain tissue were examined for each groups. RESULTS: Oxidative damage was
evident by the: (i) increase in malondialdehyde (MDA) and nitric oxide (NO)
levels in brain tissue, (ii) decrease in brain superoxide dismutase (SOD) and
glutathione peroxidase (GSH-Px) activities and (iii) increase in brain xanthine
oxidase (XO) and adenosine deaminase (ADA) activities. These alterations were
prevented by Gb treatment. Furthermore, Gb prevented the MP-induced cellular
injury in brain tissue histopathologically. CONCLUSION: Reactive oxygen species
may play a role in the mechanism that has been proposed to explain the
biological side effects of MP, and Gb prevents the MP-induced oxidative stress
to preserve antioxidant enzymes activity in brain tissue.
7
Koylu H, Mollaoglu H, Ozguner F, Nazyroglu M, Delibab N. Melatonin modulates 900 Mhz
microwave-induced lipid peroxidation changes in rat brain. Toxicol
Ind Health. 22(5):211-216, 2006.
Microwaves (MW)
from cellular phones may affect biological systems by increasing free radicals,
which may enhance lipid peroxidation levels of the brain, thus leading to
oxidative damage. Melatonin is synthesized in and secreted by the pineal gland
at night and exhibits anti-oxidant properties. Several studies suggest that
supplementation with anti-oxidant can influence MW-induced brain damage. The
present study was designed to determine the effects of MW on the brain lipid peroxidation
system, and the possible protective effects of melatonin on brain degeneration
induced by MW. Twenty-eight Sprague-Dawley male rats were randomly divided into
three groups as follows: (1) sham-operated control group (N = 8); (2) study
900-MHz MW-exposed group (N = 8); and (3) 900-MHz MW-exposed+melatonin (100
microg/kg sc before daily MW exposure treated group) (N = 10). Cortex brain and
hippocampus tissues were removed to study the levels of lipid peroxidation as
malonyl dialdehyde. The levels of lipid peroxidation in the brain cortex and
hippocampus increased in the MW group compared with the control group, although
the levels in the hippocampus were decreased by MW+melatonin administration.
The brain cortex lipid peroxidation levels were unaffected by melatonin
treatment. We conclude that melatonin may prevent MW-induced oxidative changes
in the hippocampus by streng
8
Marino AA,
Nilsen E, Frilot C. Nonlinear changes in brain electrical activity due to
cell phone radiation. Bioelectromagnetics 24(5):339-346, 2003.
We studied the effect of
an electromagnetic field from a cellular telephone on brain electrical
activity, using a novel analytical method based on a nonlinear model. The
electroencephalogram (EEG) from rabbits was embedded in phase space and local
recurrence plots were calculated and quantified using recurrence quantitation
analysis to permit statistical comparisons between filtered segments of exposed
and control epochs from individual rabbits. When the rabbits were exposed to
the radiation from a standard cellular telephone (800 MHz band, 600 mW maximum
radiated power) under conditions that simulated normal human use, the EEG was
significantly affected in nine of ten animals studied. The effect occurred
beginning about 100 ms after initiation of application of the field and lasted
approximately 300 ms. In each case, the fields increased the randomness in the
EEG. A control procedure ruled out the possibility that the observations were a
product of the method of analysis. No differences were found between exposed
and control epochs in any animal when the experiment was repeated after the
rabbits had been sacrificed, indicating that absorption of radiation by the EEG
electrodes could not account for the observed effect. No effect was seen when
deposition of energy in the brain was minimized by repositioning the radiating
antenna from the head to the chest, showing that the type of tissue that
absorbed the energy determined the observed changes in the EEG. We conclude
that, in normal use, the fields from a standard cellular telephone can alter
brain function as a consequence of absorption of energy by the brain.
9
Mausset-Bonnefont
AL, Hirbec H, Bonnefont X, Privat A, Vignon J, de Seze R.Acute exposure
to GSM 900-MHz electromagnetic fields induces glial reactivity and biochemical
modifications in the rat brain. Neurobiol Dis. 17(3):445-454, 2004.
The worldwide proliferation of mobile phones raises the question of the effects
of 900-MHz electromagnetic fields (EMF) on the brain. Using a head-only
exposure device in the rat, we showed that a 15-min exposure to 900-MHz pulsed
microwaves at a high brain-averaged power of 6 W/kg induced a strong glial
reaction in the brain. This effect, which suggests neuronal damage, was
particularly pronounced in the striatum. Moreover, we observed significant and
immediate effects on the K(d) and B(max) values of N-methyl-d-aspartate (NMDA)
and GABA(A) receptors as well as on dopamine transporters. Decrease of the
amount of NMDA receptors at the postsynaptic membrane is also reported.
Although we showed that the rat general locomotor behavior was not
significantly altered on the short term, our results provide the first evidence
for rapid cellular and molecular alterations in the rat brain after an acute exposure
to high power GSM (Global System for Mobile communication) 900-MHz microwaves.
10
Persson BRR, Salford LG, Brun A, Blood-brain barrier
permeability in rats exposed to electromagnetic fields used in wireless
communication. Wireless Network 3:455-461, 1997.
Biological
effects of radio frequency electromagnetic fields (EMF) on the blood-brain
barrier (BBB) have been studied in Fischer 344 rats of both sexes. The rats
were not anesthetised during the exposure. The brains were perfused with saline
for 3-4 minutes, and thereafter perfusion fixed with 4% formaldehyde for 5-6
minutes. Whole coronal sections of the brains were dehydrated and embedded in
paraffin and sectioned at 5 micrometers. Albumin and fibinogen were
demonstrated immunochemically and classified as normal versus pathological
leakage. In the present investigation we exposed male and female Fischer 344
rats in a Transverse Electromagnetic Transmission line camber to microwaves of
915 MHz as continuous wave (CW) and pulse-modulated with different pulse power
and at various time intervals. The CW-pulse power varied from 0.001 W to 10 W
and the exposure time from 2 min to 960 min. In each experiment we exposed 4-6
rats with 2-4 controls randomly placed in excited and non-excited TEM cells, respectively.
We have in total investigated 630 exposed rats at various modulation
frequencies and 372 controls. The frequency of pathological rats is
significantly increased (P< 0.0001) from 62/372 (ratio 0.17 + 0.02)
for control rats to 244/630 (ratio: 0.39 + 0.043) in all exposed rats.
Grouping the exposed animals according to the level or specific absorption
energy (J/kg) give significant difference in all levels above 1.5 J/kg. The
exposure was 915 MHz microwaves either pulse modulated (PW) at 217 Hz with 0.57
ms pulse width, at 50 Hz with 6.6 ms pulse width or continuous wave (CW). The
frequency of pathological rats (0.17) among controls in the various groups is
not significantly different. The frequency of pathological rats was 170/480
(0.35 + 0.03) among rats exposed to pulse modulated (PW) and 74/149
(0.50 + 0.07) among rats exposed to continuous wave exposure (CW). These
results are both highly significantly different to their corresponding controls
(p< 0.0001) and the frequency of pathological rats after exposure to pulsed
radiation (PW) is significantly less (p< 0.002) than after exposure to
continuous wave radiation (CW).
11
Testylier G
, Tonduli L, Malabiau R, Debouzy JC. Effects of exposure to low
level radiofrequency fields on acetylcholine release in hippocampus of freely
moving rats. Bioelectromagnetics
23:249-255, 2002.
Some central
cholinergic effects have been reported in animals after acute exposure to
radiofrequency electromagnetic field at low intensity. We studied acetylcholine
(ACh) release in the brain of freely moving rats exposed for 1 h during the day
to a 2.45 GHz continuous wave radiofrequency field (RF) (2 or 4 mW/cm2)
or exposed for 1 or 14 h during the night to a 800 MHz field modulated at 32 Hz
(AM 200 mW/cm2). Measurements were performed by microdialysis using
a membrane implanted through the upper CA1 region of the hippocampus. After
irradiation with the 2.45 GHz RF, rats exposed at 2 mW/cm2 did not
show a significant modification of Ach release, whereas those exposed at 4 mW/cm2
showed a significant 40% decrease in mean ACh release from hippocampus. This
decrease was maximal at 5 h post exposure. Exposure to the 800 MHz RF for 1 h
did not cause any significant effect, but exposure for 14 hrs induced a
significant 43% decrease in ACh release during the period 11 p.m.-4 a.m.
compared to control rats. In the control group we observed an increase of ACh
release at the beginning of the night, which was linked to the waking period of
rats. This normal increase was disturbed in rats exposed overnight to the 800
MHz RF. This work indicates that neurochemical modification of the hippocampal
cholinergic system can be observed during and after an exposure to low
intensity RF.
12
Vorobyov V,
Pesic V, Janac B, Prolic Z. Repeated exposure to low-level extremely low
frequency-modulated microwaves affects baseline and scopolamine-modified
electroencephalograms in freely moving rats. Int J Radiat Biol. 80(9):691-698, 2004.
PURPOSE: To compare in the
electroencephalogram of rats the effects of scopolamine (an acetylcholine
receptor antagonist) alone and after repeated exposure to low-level microwaves
modulated at extremely low frequency. MATERIALS AND METHODS: Averaged frequency
spectra (0.5-30 Hz) of the electroencephalogram were studied in freely moving
rats with carbon electrodes implanted into the somatosensory cortex. The rats
were repeatedly (3 days, 30 min day(-1)) exposed to low-intensity
(approximately = 0.3 mW cm(-2)) microwaves (915 MHz, 20-ms pulse duration),
amplitude modulated (square-wave) at extremely low frequency (4 Hz). RESULTS:
The exposure to extremely low frequency microwaves alone significantly enhanced
the fast electroencephalographic rhythms (18-30 Hz). This effect was observed
neither in subsequent sham-exposure experiment nor in radiation-naive animals.
In the microwave-exposed rats, scopolamine (0.1 mg kg(-1), subcutaneously) did
not cause a slowing in the electroencephalogram that was shown in non-exposed
rats. A similarity between the scopolamine-induced electroencephalogram effect
in the microwave-exposed rats and that of physostigmine (enhancing the
acetylcholine level in the brain) in radiation-naive animals was noted. This
paradoxical phenomenon stimulates new experimentation for understanding its
mechanism(s). CONCLUSIONS: The data obtained provide additional evidence that
repeated low-level exposure to extremely low frequency microwaves can modify an
activity of cholinergic system in the brain.
13
Wang Q, Cao ZJ, Bai XT. [Effect of 900 MHz
electromagnetic fields on the expression of GABA receptor of cerebral cortical
neurons in postnatal rats] Wei Sheng Yan Jiu. 34(5):546-548, 2005.
OBJECTIVE: To investigate the effects of 900 MHz microwave electromagnetic
fields (EMF) on the expression of neurotransmitter GABA receptor of cerebral
cortical neurons in postnatal rats. METHODS: Neurons were exposed to 900 MHz
continuous microwave EMF (SAR = 1.15 - 3.22mW/g) for 2 hours per day in 6
consecutive days and for 12 hours at one time. GABA receptor was chosen to be
the biological end. RESULTS: Significant changes had been observed in exposed
neurons in the expression of GABA receptor. (P < 0.01) . CONCLUSION: The
expression of GABA receptor of neurons were significantly regulated by 900 MHz
microwave, and a power "window" effect was observed in the exposed
neurons.
14
Xu S, Ning W, Xu Z, Zhou S, Chiang H, Luo J. Chronic exposure to GSM 1800-MHz microwaves reduces excitatory synaptic
activity in cultured hippocampal neurons. Neurosci Lett. 2006 Jan 25; [Epub ahead of print]
The world wide proliferation of mobile phones raises the concern about the
health effects of 1800-MHz microwaves on the brain. The present study assesses
the effects of microwave exposure on the function of cultured hippocampal
neurons of rats using whole cell patch-clamp analysis combined with
immunocytochemistry. We showed that chronic exposure (15min per day for 8 days)
to Global System for Mobile Communication (GSM) 1800-MHz microwaves at specific
absorption rate (SAR) of 2.4W/kg induced a selective decrease in the amplitude
of alpha-amino-3-hydroxy-5-methyl-4-soxazole propionic acid (AMPA) miniature
excitatory postsynaptic currents (mEPSCs), whereas the frequency of AMPA mEPSCs
and the amplitude of N-methyl-d-aspartate (NMDA) mEPSCs did not change. Furthermore,
the GSM microwave treatment decreased the expression of postsynaptic density 95
(PSD95) in cultured neurons. Our results indicated that 2.4W/kg GSM 1800-MHz
microwaves may reduce excitatory synaptic activity and the number of excitatory
synapses in cultured rat hippocampal neurons.
15
Zhao TY, Zou SP, Knapp PE Exposure to cell phone radiation up-regulates
apoptosis genes in primary cultures of neurons and astrocytes. Neurosci Lett.
2006 Dec 20; [Epub ahead of print].
The health effects of cell
phone radiation exposure are a growing public concern. This study investigated
whether expression of genes related to cell death pathways are dysregulated in
primary cultured neurons and astrocytes by exposure to a working Global System
for Mobile Communication (GSM) cell phone rated at a frequency of 1900MHz.
Primary cultures were exposed to cell phone emissions for 2h. We used array
analysis and real-time RT-PCR to show up-regulation of caspase-2, caspase-6 and
Asc (apoptosis associated speck-like protein containing a card) gene expression
in neurons and astrocytes. Up-regulation occurred in both "on" and
"stand-by" modes in neurons, but only in "on" mode in
astrocytes. Additionally, astrocytes showed up-regulation of the Bax gene. The
effects are specific since up-regulation was not seen for other genes
associated with apoptosis, such as caspase-9 in either neurons or astrocytes,
or Bax in neurons. The results show that even relatively short-term exposure to
cell phone radiofrequency emissions can up-regulate elements of apoptotic
pathways in cells derived from the brain, and that neurons appear to be more
sensitive to this effect than astrocytes.
16
Beason RC, Semm P. Responses of neurons to an
amplitude modulated microwave stimulus. Neurosci Lett 333(3):175-178, 2002.
In this study we investigated the effects of a pulsed radio frequency signal
similar to the signal produced by global system for mobile communication
telephones (900 MHz carrier, modulated at 217 Hz) on neurons of the avian
brain. We found that such stimulation resulted in changes in the amount of
neural activity by more than half of the brain cells. Most (76%) of the
responding cells increased their rates of firing by an average 3.5-fold. The
other responding cells exhibited a decrease in their rates of spontaneous
activity Such responses indicate potential effects on humans using hand-held
cellular phones.
4. Observed whole Body response
1
Dasdag, S, Ketani, MA, Akdag, Z, Ersay, AR, Sar,i I,
Demirtas ,OC, Celik, MS, Whole-body microwave exposure emitted by cellular
phones and testicular function of rats. Urol
Res 27(3):219-223, 1999.
This study
investigated whether there are adverse effects due to microwave exposure
emitted by cellular phones in male rats. Eighteen Wistar Albino rats were
separated into three groups, a sham group and two experimental groups. The rats
were confined in Plexiglas cages and cellular phones were placed 0.5 cm under
the cages. In the first experimental group, cellular phones were in standby
position for 2 h. In the second experimental group, phones were turned to the
speech position three times each for 1 min duration over 2 h. Rats in the first
and second experimental groups were exposed to microwaves emitted by phones for
2 h/day for a duration of 1 month. After the last exposure the rats were
killed. Brain, eyes, ears, liver, heart, lungs, stomach, kidneys, testes, small
and large intestines and skin of the rats were observed histologically. The
decrease of epididymal sperm counts in the speech groups were not found to be
significant (P > 0.05). Differences in terms of normal and abnormal sperm
forms were not observed (P > 0.05). Histological changes were especially
observed in the testes of rats of the speech groups. Seminiferous tubular
diameter of rat testes in the standby and speech groups was found to be lower
than the sham group (P < 0.05). Rectal temperatures of rats in the speech
group were found to be higher than the sham and standby groups (P < 0.05).
The rectal temperatures of rats before and after exposure were also found to be
significantly higher in the speech group (P < 0.05). Specific absorption
rate (SAR) was determined as 0.141 W/kg.
2
Singh B, Bate
LA, Responses of pulmonary intravascular macrophages to 915-MHz microwave
radiation: ultrastructural and cytochemical study. Anat Rec 246(3):343-355, 1996.
BACKGROUND: Microwave
(MW) radiation is being increasingly used as a source of heat supplementation
during early postnatal development of pigs. Although MW radiation does not
cause deleterious physiological effects, no specific information exists
regarding its impact on immune cells such as macrophages. Pulmonary intravascular
macrophages (PIMs) are emerging as important inflammatory cells due to their
endocytic and secretory potential. An in vivo study was conducted to evaluate
the effects of infrared, and low and high power MW radiation on the PIMs of
pigs. METHODS: Pigs were exposed to infrared (IR), low MW (LMW; 6.1mW cm-2),
and high MW (HMW; 11.4mW cm-2) radiation at 915 MHz (n = 2 for each treatment)
for 24 hr. The controls (n = 2) were exposed to natural light for the same
period of time. Lung tissues were processed for ultrastructural examination and
acid phosphatase (AcPase) cytochemistry. In addition, rough endoplasmic
reticulum (RER) as a fraction of cytosol of the PIMs was counted. RESULTS:
Ultrastructural and numerical data suggested enhanced secretory activity in the
PIMs of LMW-treated pigs as indicated by the increased RER:cytoplasm ratio,
prominent Golgi complex profiles, and accumulation of secretory vesicles in
conjunction with microtubules as compared with the control, IR, and HMW-exposed
pigs. High MW treatment induced some damage to pulmonary interstitium as
deduced from the presence of extracellular AcPase precipitates and disrupted
collagen matrix. Intracellular globules were noticed in the PIMs of IR and
LMW-treated pigs but not in the control and HMW-radiated animals. CONCLUSIONS:
Elaboration of structural signs of secretory activity in the PIMs by LMW
radiation in the absence of pulmonary pathological changes indicates its
potential for cell activation in addition to the already established role of
LMW in heat supplementation. This activation could be due to either increased
core body temperature or initiation of intracellular signaling by the LMW
radiation. This study also shows that the HMW radiation is capable of inducing
pathology in the form of changes in the pulmonary interstitial matrix and may
not be a good source of supplementary heat.
5. Measured Changes to body Chemistry
1
Aksen F, Dasdag S, Akdag MZ, Askin M, Dasdag MM. The effects
of whole body cell phone exposure on the T1 relaxation times and trace elements
in the serum of rats. Electromag. Biol. Med. 23:7-11, 2004.
The objective of this study was to
investigate the effects of radiofrequency radiation emitted from cellular
phones on: (1) trace elements such as manganese, iron, copper, zinc, (2) T1
relaxation times in serum, and (3) rectal temperature of rats exposed to
microwave radiation emitted from cellular phones. Sixteen Spraque-Dawley rats
were separated into two groups of eight, one sham-exposed (control) and one
exposed (experimental). The rats were confined in Plexiglas cages and a
cellular phone was placed 0.5 cm under the cage. For the experimental
group, cellular phones were activated 20 min per day, 7 days a week, for 1
month. For the control group, a cellular phone placed beneath the cage for
20 min a day was turned off. Rectal temperatures were measured weekly. For
250-mW-radiated powers, the whole body average specified absorption rate (SAR)
(rms) is 0.52 W/kg and 1-g-averaged peak SAR (rms) is 3.13 W/kg. The
Mann-Whitney U test was used for statistical comparisons of groups. T1
relaxation time and the values of iron and copper in the serum of the
experimental group were not changed compared to the control group (p > 0.05).
However, manganese and zinc values in the serum of the experimental group were
significantly different from the control group (p < 0.05).
The difference in rectal temperature measured before and after exposure in the
experimental groups was not statistically different from control (p > 0.05).
2
Barteri M, Pala A, Rotella S. Structural and
kinetic effects of mobile phone microwaves on acetylcholinesterase activity. Biophys Chem. 113(3):245-253, 2005.
The present study provides evidence that "in vitro" simple exposure
of an aqueous solution of electric eel acetylcholinesterase (EeAChE; EC
3.1.1.7.) to cellular phone emission alters its enzymatic activity. This paper
demonstrates, by combining different experimental techniques, that radio
frequency (RF) radiations irreversibly affect the structural and biochemical
characteristics of an important CNS enzyme. These results were obtained by
using a commercial cellular phone to reproduce the reality of the human
exposition. This experimental procedure provided surprising effects collected
practically without experimental errors because they were obtained comparing
native and irradiated sample of the same enzyme solution. Although these
results cannot be used to conclude whether exposure to RF during the use of
cellular phone can lead to any hazardous health effect, they may be a
significant first step towards further verification of these effects on other
"ex vivo" or "in vivo" biological systems.
3
Koyu A, Cesur G, Ozguner F, Akdogan M, Mollaoglu H, Ozen S. Effects of
900MHz electromagnetic field on TSH and thyroid hormones in rats. Toxicol Lett. 157(3):257-262, 2005b.
In this study, the effects of exposure to a 900megahertz (MHz) electromagnetic
field (EMF) on serum thyroid stimulating hormone (TSH) and
triiodothronine-thyroxin (T(3)-T(4)) hormones levels of adult male
Sprague-Dawley rats were studied. Thirty rats were used in three independent
groups, 10 of which were control (without stress and EMF), 10 of which were
exposed to 900MHz EMF and 10 of which were sham-exposed. The exposures were
performed 30min/day, for 5days/week for 4 weeks to 900MHz EMF. Sham-exposed
animals were kept under the same environmental conditions as the study groups
except with no EMF exposure. The concentration of TSH and T(3)-T(4) hormones in
the rat serum was measured by using an immunoradiometric assay (IRMA) method
for TSH and a radio-immunoassay (RIA) method for T(3) and T(4) hormones. TSH
values and T(3)-T(4) at the 900MHz EMF group were significantly lower than the
sham-exposed group (p<0.01). There were no statistically significant
differences in serum TSH values and T(3)-T(4) hormone concentrations between
the control and the sham-exposed group (p>0.05). These results indicate that
900MHz EMF emitted by cellular telephones decrease serum TSH and T(3)-T(4)
levels.
4
Leszczynski D, Joenväärä S,
Reivinen J, Kuokka R, Non-thermal
activation of the hsp27/p38MAPK stress pathway by mobile phone radiation in
human endothelial cells: Molecular mechanism for cancer- and blood-brain
barrier-related effects. Differentiation 70:120 - 129, 2002.
We have examined whether non-thermal exposures of cultures of the human
endothelial cell line EA.hy926 to 900 MHz GSM mobile phone microwave radiation
could activate stress response. Results obtained demonstrate that 1-hour
non-thermal exposure of EA.hy926 cells changes the phosphorylation status of
numerous, yet largely unidentified, proteins. One of the affected proteins was
identified as heat shock protein-27 (hsp27). Mobile phone exposure caused a transient increase in
phosphorylation of hsp27, an effect which was prevented by SB203580, a
specific inhibitor of p38 mitogen-activated protein kinase (p38MAPK). Also, mobile phone exposure
caused transient changes in the protein expression levels of hsp27 and p38MAPK.
All these changes were non-thermal effects because, as determined using
temperature probes, irradiation did not alter the temperature of cell cultures,
which remained throughout the irradiation period at 37 ± 0.3 °C. Changes in the overall pattern of protein
phosphorylation suggest that mobile phone radiation activates a variety of
cellular signal transduction pathways, among them the hsp27/p38MAPK stress
response pathway. Based on the known functions of hsp27, we put forward the
hypothesis that mobile phone radiation-induced activation of hsp27 may (i) facilitate the development of
brain cancer by inhibiting the cytochrome c/caspase-3 apoptotic pathway
and (ii) cause an increase
in blood-brain barrier permeability through stabilization of endothelial
cell stress fibers. We postulate that these events, when occurring repeatedly
over a long period of time, might become a health hazard because of the
possible accumulation of
brain tissue damage. Furthermore, our hypothesis suggests that other brain damaging
factors may co-participate in mobile phone radiation-induced effects.
5
Moustafa YM, Moustafa RM, Belacy A, Abou-El-Ela SH,
Ali FM.
Effects of acute exposure to the radiofrequency fields of cellular
phones on plasma lipid peroxide and antioxidase activities in human
erythrocytes. J
Pharm Biomed Anal
26(4):605-608, 2001.
Radiofrequency fields of cellular phones may affect biological systems by
increasing free radicals, which appear mainly to enhance lipid peroxidation,
and by changing the antioxidase activities of human blood thus leading to
oxidative stress. To test this, we have investigated the effect of acute
exposure to radiofrequency fields of commercially available cellular phones on
some parameters indicative of oxidative stress in 12 healthy adult male
volunteers. Each volunteer put the phone in his pocket in standby position with
the keypad facing the body. The parameters measured were lipid peroxide and the
activities of superoxide dismutase (SOD), total glutathione peroxidase (GSH-Px)
and catalase. The results obtained showed that the plasma level of lipid
peroxide was significantly increased after 1, 2 and 4 h of exposure to
radiofrequency fields of the cellular phone in standby position. Moreover, the
activities of SOD and GSH-Px in human erythrocytes showed significant reduction
while the activity of catalase in human erythrocytes did not decrease
significantly. These results indicate that acute exposure to radiofrequency
fields of commercially available cellular phones may modulate the oxidative
stress of free radicals by enhancing lipid peroxidation and reducing the
activation of SOD and GSH-Px, which are free radical scavengers. Therefore,
these results support the interaction of radiofrequency fields of cellular
phones with biological systems.
6
Weisbrot D,
Lin H, Ye L, Blank M, Goodman R. Effects of mobile phone
radiation on reproduction and development in Drosophila melanogaster. J Cell Biochem 89(1):48-55, 2003.
In this report we examined the effects of a discontinuous radio frequency (RF)
signal produced by a GSM multiband mobile phone (900/1,900 MHz; SAR
approximately 1.4 W/kg) on Drosophila melanogaster, during the 10-day
developmental period from egg laying through pupation. As found earlier with
low frequency exposures, the non-thermal radiation from the GSM mobile phone
increased numbers of offspring, elevated hsp70 levels, increased serum response
element (SRE) DNA-binding and induced the phosphorylation of the nuclear
transcription factor, ELK-1. The rapid induction of hsp70 within minutes, by a
non-thermal stress, together with identified components of signal transduction
pathways, provide sensitive and reliable biomarkers that could serve as the
basis for realistic mobile phone safety guidelines.
7
Yariktas M,
Doner F, Ozguner F, Gokalp O, Dogru H, Delibas N. Nitric oxide level in the
nasal and sinus mucosa after exposure to electromagnetic field. Otolaryngol Head Neck Surg.
132(5):713-716, 2005.
OBJECTIVE: The purpose of this study was to examine the changes in nitric oxide
(NO) level in the nasal and paranasal sinus mucosa after exposure
radiofrequency electromagnetic fields (EMF). STUDY DESIGN AND SETTING: Thirty
male Sprague-Dawley rats were randomly grouped as follows: EMF group (group I;
n, 10), EMF group in which melatonin received (group II; n, 10) and the control
(sham operated) group (group III; n, 10). Groups I and II were exposed to a 900
MHz. Oral melatonin was given in group II. Control rats (group III) were also
placed in the tube as the exposure groups, but without exposure to EMF. At the
end of 2 weeks, the rats were sacrificed, and the nasal and paranasal sinus
mucosa dissected. NO was measured in nasal and paranasal mucosa. RESULTS: The
nasal and paranasal sinus mucosa NO levels of group I were significantly higher
than those of the control group (group III) ( P < 0.05). However, there was
no statistically significant difference between group II and the control group
(group III) regarding NO output ( P > 0.05). CONCLUSION: Exposure to EMF
released by mobile phones (900 MHz) increase NO levels in the sinus and nasal
mucosa. SIGNIFICANCE: Increased NO levels may act as a defense mechanism and
presumably related to tissue damage. In addition, melatonin may have beneficial
effect to prevent these changes in the mucosa.
8
The ever
increasing use of cellular phones and the increasing number of associated base
stations are becoming a widespread source of nonionizing electromagnetic
radiation. Some biological effects are likely to occur even at low-level EM
fields. In this study, a gigahertz transverse electromagnetic (GTEM) cell was
used as an exposure environment for plane wave conditions of far-field free
space EM field propagation at the GSM base transceiver station (BTS) frequency
of 945 MHz, and effects on oxidative stress in rats were investigated. When EM
fields at a power density of 3.67 W/m2 (specific absorption rate = 11.3 mW/kg),
which is well below current exposure limits, were applied, MDA
(malondialdehyde) level was found to increase and GSH (reduced glutathione)
concentration was found to decrease significantly (p < 0.0001).
Additionally, there was a less significant (p = 0.0190) increase in SOD
(superoxide dismutase)
9
Zeng QL, Weng Y, Chen GD, Lu DQ, Chiang H, Xu ZP [Effects of GSM 1800 MHz
radiofrequency electromagnetic fields on protein expression profile of human
breast cancer cell MCF-7.] Zhonghua
Yu Fang Yi Xue Za Zhi. 40(3):153-158, 2006.
[Article in Chinese]
OBJECTIVE: To study the effects of GSM 1800 MHz radiofrequency electromagnetic
fields (RF EMF) exposure on protein expression profile of human breast cancer
cell line (MCF-7), as to exploring the possible effects on normal cell
physiological function. METHODS: MCF-7 cells were continuously or
intermittently (5 minutes field on followed by 10 minutes off) exposed to RF
EMF for different duration (1 hour, 3 hours, 6 hours, 12 hours, or 24 hours) at
an average specific absorption rate (SAR) of 3.5 W/kg. The extracted proteins
were separated by 2-dimensional electrophoresis and the protein-spot
distribution of the sliver-stained gels was analyzed by using PDQuest software
7.1. Each experiment was repeated three times. RESULTS: On the average, around
1100 proteins were detected using pH 4 - 7 IPG strip. There were no
differential proteins found under continuous exposure at SAR of 3.5 W/kg for 6
hours. Under other exposure conditions, we found various differentially
expressed proteins in exposure groups as compared with the sham-exposed
controls. Especially in 3 hours intermittent exposure and 12 hours continuous
exposure, eighteen and seven differential proteins were detected, respectively.
The categories and functions of these differentially expressed proteins were
analyzed by searching of SWISS-PROT protein database, which suggested that
these proteins should be related to the functions of biosynthesization, signal
transduction, and DNA damage and repair. CONCLUSIONS: Data indicated that the
protein expression changes induced by RF radiation might depend on exposure
duration and mode. Many biological processes might be affected by RF exposure.
6. Measured Cellular
Chemistry alterations
Gene expression, DNA synthesis, heat-shock proteins,
RNA, etc.
1
Czyz J ,
Guan K, Zeng Q, Nikolova T, Meister A, Schönborn F, Schuderer J, Kuster N, Wobus AM, High frequency electromagnetic fields
(GSM signals) affect gene expression levels in tumor suppressor p53-deficient
embryonic stem cells. Bioelectromagnetics
25:296-307, 2004.
Effects
of electromagnetic fields (EMF) simulating exposure to the Global System for
Mobile Communications (GSM) signals were studied using pluripotent embryonic
stem (ES) cells in vitro. Wild-type ES cells and ES cells deficient for the
tumor suppressor p53 were exposed to pulse modulated EMF at 1.71 GHz, lower end
of the uplink band of GSM 1800, under standardized and controlled conditions,
and transcripts of regulatory genes were analyzed during in vitro
differentiation. Two dominant GSM modulation schemes (GSM-217 and GSM-Talk),
which generate temporal changes between GSM-Basic (active during talking
phases) and GSM-DTX (active during listening phases thus simulating a typical
conversation), were applied to the cells at and below the basic safety limits
for local exposures as defined for the general public by the International
Commission on Nonionizing Radiation Protection (ICNIRP). GSM-217 EMF induced a
significant upregulation of mRNA levels of the heat shock protein, hsp70 of
p53-deficient ES cells differentiating in vitro, paralleled by a low and
transient increase of c-jun, c-myc, and p21 levels in p53-deficient, but not in
wild-type cells. No responses were observed in either cell type after EMF
exposure to GSM-Talk applied at similar slot-averaged specific absorption rates
(SAR), but at lower time-averaged SAR values. Cardiac differentiation and cell
cycle characteristics were not affected in embryonic stem and embryonic
carcinoma cells after exposure to GSM-217 EMF signals. Our data indicate that
the genetic background determines cellular responses to GSM modulated EMF.
2
Di
Carlo A, White N, Guo F, Garrett P, Litovitz T. Chronic electromagnetic field exposure
decreases HSP70 levels and lowers cytoprotection. J. Cell. Biochem. 84: 447-454, 2002.
Electromagnetic field (EMF) exposures have
been shown to induce heat shock proteins (HSPs), which help to maintain the
conformation of cellular proteins during periods of stress. We have previously
reported that short-term exposure of chick embryos to either 60 Hz (extremely
low frequency: ELF), or radio-frequency (RF: 915 MHz) EMFs induce protection
against hypoxia. Experiments presented in the current report are based on a
study in which long-term (4 days), continuous exposure to ELF-EMFs decreased protection against ultraviolet
radiation. Based on this result, it was hypothesized that de-protection against
hypoxia should also occur following long-term, continuous, or daily, repeated
exposures to EMFs. To test this hypothesis, chick embryos were exposed to
ELF-EMFs (8 T) continuously for 4 days, or to ELF or RF
(3.5 mW incident power)- EMFs repeated daily (20, 30, or 60 min once or twice
daily for 4 days). Several of the exposure protocols yielded embryos that had
statistically significant decreases in protection against hypoxic stress
(continuous and 30 or 60 min ELF twice daily; or 30 or 60 min once daily RF).
This is consistent with our finding that following 4 days of ELF-EMF exposure,
HSP70 levels decline by 27% as compared to controls. In addition, the
superposition of ELF-EM noise, previously shown to minimize ELF-EMF induced
hypoxia protection, inhibited hypoxia de-protection caused by long term,
continuous ELF or daily, repeated RF exposures. This EMF-induced decrease in
HSP70 levels and resulting decline in cytoprotection suggests a mechanism by
which daily exposure (such as might be experienced by mobile phone users) could enhance the probability of
cancer and other diseases.
3
Donnellan M, McKenzie DR, French PW, Effects
of exposure to electromagnetic radiation at 835 MHz on growth, morphology and
secretory characteristics of a mast cell analogue, RBL-2H3. Cell
Biol Int 21:427-439, 1997.
A mast cell line, RBL-2H3, was exposed to 835 MHz for 20 minutes, three times
per day for 7 days at a power density of 8.1 +/- 3 mW/cm2. From day 4 onwards,
it was observed that the rate of DNA synthesis and cell replication increased,
that actin distribution and cell morphology became altered, and the amount of
beta-hexosaminidase (a marker of granule secretion) released in response to a
calcium ionophore was significantly enhanced, in comparison to unexposed
cultures. There were no effects seen on levels of cytoskeletal protein
synthesis or of beta-actin mRNA. Morphological changes persisted following
subculture for at least 7 days in the absence of further exposure. It is
hypothesized that effects of exposure to an electromagnetic field at 835 MHz
may be mediated via a signal transduction pathway.
4
French PW, Donnellan M, McKenzie DR, Electromagnetic
radiation at 835 MHz changes the morphology and inhibits proliferation of a
human astrocytoma cell line. Bioelectrochem
Bioenerg 43:13-18, 1997.
A human
astrocytoma cell line, U-87 MG, was exposed to 835 MHz electromagnetic
radiation for 20 min, 3 times per day for 7 days, at a power density of either
40+15 mWcm-2 or 8.1 + 3 mWcm-2. At the low power density, it was observed
that the rate of DNA synthesis decreased, and that the cells flattened and
spread out in comparison to unexposed culture. At 40 mWcm-2, there
were no effects seen on cell proliferation, but alteration in cell morphology
included increased cell spreading and also the appearance of actin-containing
blebs at localized sites on the membrane. It is hypothesised that 835 MHz
radiation at low power density may be affecting a signal transduction pathway
involved in cell proliferation.
5
Goswami PC, Albee LD, Parsian AJ, Baty JD, Moros EG,
Pickard WF, Roti Roti JL, Hunt CR, Proto-oncogene mRNA levels and activities of
multiple transcription factors in C3H 10T 1/2 murine embryonic fibroblasts
exposed to 835.62 and 847.74 MHz cellular phone communication frequency
radiation. Radiat Res 151(3):300-309,
1999.
This study was
designed to determine whether two differently modulated
radiofrequencies
of the type generally used in cellular phone communications
could
elicit a general stress response in a biological system. The two modulations
and frequencies studied were a frequency-modulated continuous wave (FMCW) with
a carrier frequency of 835.62 MHz and a code division multiple-access (CDMA)
modulation centered on 847.74 MHz. Changes in proto-oncogene expression,
determined by measuring Fos, Jun, and Myc mRNA levels as well as by the
DNA-binding activity of the AP1, AP2 and NF-kappaB transcription factors, were
used as indicators of a general stress response. The effect of radiofrequency
exposure on proto-oncogene expression was assessed (1) in exponentially growing
C3H 10T 1/2 mouse embryo fibroblasts during their transition to plateau phase
and (2) during transition of serum-deprived cells to the proliferation cycle
after serum stimulation. Exposure of serum-deprived cells to 835.62 MHz FMCW or
847.74 MHz CDMA microwaves (at an average specific absorption rate, SAR, of 0.6
W/kg) did not significantly change the kinetics of proto-oncogene expression
after serum stimulation. Similarly, these exposures did not affect either the
Jun and Myc mRNA levels or the DNA-binding activity of AP1, AP2 and NF-kappaB
in exponential cells during transit to plateau-phase growth. Therefore, these
results suggest that the radiofrequency exposure is unlikely to elicit a
general stress response in cells of this cell line under these conditions.
However, statistically significant increases (approximately 2-fold, P = 0.001)
in Fos mRNA levels were detected in exponential cells in transit to the plateau
phase and in plateau-phase cells exposed to 835.62
MHz FMCW
microwaves. For 847.74 MHz CDMA exposure, the increase was 1.4-fold (P = 0.04).
This increase in Fos expression suggests that expression of specific genes
could be affected by radiofrequency exposure.
6
Harvey C, French PW, Effects on protein kinase C and
gene expression in a human mast cell line, HMC-1, following microwave exposure.
Cell Biol Int 23(11):739-748, 2000.
We used a
resonant cavity which delivered a continuous wave exposure at 864.3 MHz at an
average specific absorption rate (SAR) of 7 W/kg to determine non-thermal
biological effects of microwave exposure. A human mast cell line, HMC-1, was
used as the biological target. Cells were given three exposures each of 20-min
duration daily for 7 days. The temperature of the cell culture medium during
the exposure fell to 26.5 degrees C. Effects were seen on localization of
protein kinase C, and expression of three genes of 588 screened. The affected
genes included the proto-oncogene c-kit, the transcription factor Nucleoside
diphosphate kinase B and the apoptosis-associated gene DAD-1. Stress response
genes were variably upregulated. No significant effect on morphology or on
F-actin distribution was detected. We conclude that low-power microwave exposure may act on HMC-1 cells by
altering gene expression via a mechanism involving activation of protein kinase
C, and at temperatures well below those known to induce a heat shock response.
7
Irmak MK, Fadillioglu E, Gulec M, Erdogan H, Yagmurca M, Akyol O. Effects of electromagnetic radiation from a cellular telephone on the
oxidant and antioxidant levels in rabbits. Cell Biochem Funct. 20(4):279-283, 2002.
The number of reports on the effects induced by electromagnetic radiation (EMR)
in various cellular systems is still increasing. Until now no satisfactory
mechanism has been proposed to explain the biological effects of this
radiation. Oxygen free radicals may play a role in mechanisms of adverse
effects of EMR. This study was undertaken to investigate the influence of
electromagnetic radiation of a digital GSM mobile telephone (900 MHz) on
oxidant and antioxidant levels in rabbits. Adenosine deaminase, xanthine
oxidase, catalase, myeloperoxidase, superoxide dismutase (SOD) and glutathione
peroxidase activities as well as nitric oxide (NO) and malondialdehyde levels
were measured in sera and brains of EMR-exposed and sham-exposed rabbits. Serum
SOD activity increased, and serum NO levels decreased in EMR-exposed animals
compared to the sham group. Other parameters were not changed in either group.
This finding may indicate the possible role of increased oxidative stress in
the pathophysiology of adverse effect of EMR. Decreased NO levels may also
suggest a probable role of NO in the adverse effect.
8
Irmak MK, Oztas E, Yagmurca M, Fadillioglu E,
Bakir B.
Effects of electromagnetic radiation from a cellular telephone on epidermal
Merkel cells. J Cutan
Pathol. 30(2):135-138, 2003.
The number of reports on the
effects induced by electromagnetic radiation (EMR) from cellular telephones in
various cellular systems is still increasing. Until now, no satisfactory
mechanism has been proposed to explain the biological effects of this radiation
except a role suggested for mast cells. Merkel cells may also play a role in
the mechanisms of biological effects of EMR. This study was undertaken to
investigate the influence of EMR from a cellular telephone (900 MHz) on Merkel
cells in rats. A group of rats was exposed to a cellular telephone in speech
position for 30 min. Another group of rats was sham-exposed under the same
environmental conditions for 30 min. Exposure led to significantly higher
exocytotic activity in Merkel cells compared with the sham exposure group. This
finding may indicate the possible role of Merkel cells in the pathophysiology
of the effects of EMR.
9
Kwee S,
Raskmark P, Changes in cell
proliferation due to environmental non-ionizing radiation 2. Microwave
radiation. Bioelectrochem Bioenerg 44(2) 251-255, 1998.
Due to the use of mobile telephones, there
is an increased exposure of the environment to weak radiofrequency (RF)
electromagnetic fields, emitted by these devices. This study was undertaken to
investigate if the microwave radiation from these fields will have a similar effect
on cell proliferation as weak electromagnetic (ELF) fields. The field was
generated by signal simulation of the Global System for Mobile communications
(GSM) of 960 MHz. Cell cultures, growing in microtiter plates, were exposed in
a specially constructed chamber, a Transverse Electromagnetic (TEM) cell. The
Specific Absorption Rate (SAR) values for each cell well were calculated for
this exposure system. Experiments were performed on cell cultures of
transformed human epithelial amnion cells (AMA), which were exposed to 960 MHz
microwave fields at three different power levels and three different exposure
times, respectively. It was found that cell growth in the exposed cells was
decreased in comparison to that in the control and sham exposed cells. Cell proliferation
during the period following exposure varied not only with the various SAR
levels, but also with the length of exposure time. On the other hand, repeated
periods of exposure did not seem to change the effects. There was a general
linear correlation between power level and growth change. However, the exposure
time required to obtain the maximum effect was not the same for the various
power levels. It turned out that at low power level, a maximum effect was first
reached after a longer exposure time than at higher power level. A similar
phenomenon was registered in the studies on ELF electromagnetic fields. Here,
it was found that there was a linear correlation between the length of exposure
time to obtain maximum effect and field strength.
10
Kwee S,
Raskmark P, Velizarov P. Changes in cellular proteins
due to environmental non-ionizing radiation. I. Heat-shock proteins. Electro- and Magnetobiology 20: 141-152, 2001.
This paper
describes the effect of weak microwave fields on the amounts of heat-shock
proteins in cell cultures at various temperatures. The field was generated by
signal simulation of the Global System for Mobile communications (GSM) of 960
Mhz, used in portable phones. Transformed human epithelial amnion (AMA) cells,
growing on glass coverslips, were exposed in a transverse electromagnetic (TEM)
cell to a microwave field, generating a specific absorption rate (SAR) of 2.1
mW.kg-1 in the cells. Exposure temperatures were 35, 37, and
40 ± 0.1°C, respectively, and the exposure time was 20 min. The heat-shock
proteins Hsp-70 and Hsp-27 were detected by immuno-fluorescence. Higher amounts
of Hsp-70 were present in the cells exposed at 35 and 37°C than in the
sham-exposed cells. These effects can be considered to be athermal, since the field
strength was much lower than the safety standard for absence of heat generation
by microwave fields. There was no significant response in the case of Hsp-27.
11
Markova E, Hillert L, Malmgren L, Persson BR, Belyaev IY. Microwaves
from GSM Mobile Telephones Affect 53BP1 and gamma-H2AX Foci in Human
Lymphocytes from Hypersensitive and Healthy Persons. Environ Health Perspect. 113(9):1172-1177,
2005.
The data on biologic effects of nonthermal microwaves (MWs) from mobile
telephones are diverse, and these effects are presently ignored by safety
standards of the International Commission for Non-Ionizing Radiation Protection
(ICNIRP). In the present study, we investigated effects of MWs of Global System
for Mobile Communication (GSM) at different carrier frequencies on human
lymphocytes from healthy persons and from persons reporting hypersensitivity to
electromagnetic fields (EMFs). We measured the changes in chromatin
conformation, which are indicative of stress response and genotoxic effects, by
the method of anomalous viscosity time dependence, and we analyzed tumor
suppressor p53-binding protein 1 (53BP1) and phosphorylated histone H2AX
(gamma-H2AX), which have been shown to colocalize in distinct foci with DNA
double-strand breaks (DSBs), using immunofluorescence confocal laser
microscopy. We found that MWs from GSM mobile telephones affect chromatin
conformation and 53BP1/gamma-H2AX foci similar to heat shock. For the first
time, we report here that effects of MWs from mobile telephones on human
lymphocytes are dependent on carrier frequency. On average, the same response
was observed in lymphocytes from hypersensitive and healthy subjects.
12
Mancinelli F,
Caraglia M, Abbruzzese A, d'Ambrosio G, Massa R, Bismuto E. Non-thermal
effects of electromagnetic fields at mobile phone frequency on the refolding of
an intracellular protein: myoglobin. J Cell Biochem. 93(1):188-196, 2004.
Non-thermal effects induced by exposure to microwave electromagnetic field
(MW-EMF) at 1.95 MHz, a frequency used in mobile communication, have been
observed on the refolding kinetics of the heme binding site in an intracellular
protein: tuna myoglobin, starting from acidic conditions. We have selected myoglobin
because it can be considered a good model to study protein interactions with
MW-EMF for its well-known high-resolution crystallographic structure. Myoglobin
solutions at pH 3.0 were subjected to 3 h exposure to microwave field (with a
specific absorption rate of 51 +/- 1 mW/g); the heme site refolding has been
followed by measuring the molecular absorption in the Soret spectral region and
the data were fitted to a bi-exponential model. The kinetics of exposed samples
appear to be slowered by MW-EMF action. Moreover, the tryptophanyl lifetime
distribution of the exposed protein, as deduced by the analysis of the
fluorescence emission decay from its single tryptophan, appears sharper if
compared to non-exposed protein samples. This observation suggests that the
presence of MW-EMF could affect the propensity of protein molecules to populate
specific conformational substates among which myoglobin molecules fluctuate at
acidic pH. Changes in the structural fluctuation caused by MW perturbation can
affect differently the aggregation process that occurs competitively during the
protein folding, so representing a potential risk for protein
"misfolding." These data suggest that MW-EMF could have also
biochemical and, consequently, biological effects on eukaryotic cells that are
still under investigation.
13
Nylund
R, Leszczynski D. Proteomics analysis of human endothelial cell line EA.hy926
after exposure to GSM 900 radiation. Proteomics 4:1359-1365, 2004.
The
human endothelial cell line EA.hy926 was exposed to mobile phone radiation and
the effect on protein expression was examined using two-dimensional
electrophoresis (2-DE). Up to 38 various proteins have statistically
significantly altered their expression levels following the irradiation. Four
proteins were identified with matrix-assisted laser desorption/ionization-mass
spectrometry (MALDI-MS). Two of the affected proteins were determined
to be isoforms of cytoskeletal vimentin. This finding supports our earlier
presented working hypothesis which indicated that the mobile phone radiation
might affect the cytoskeleton and might have an effect on the physiological
functions that are regulated by the cytoskeleton.
14
Nylund R, Leszczynski D.Mobile phone radiation causes changes in gene
and protein expression in human endothelial cell lines and the response seems
to be genome- and proteome-dependent. Proteomics.
2006 Jul 28; [Epub ahead of print]
We have examined in vitro cell response to
mobile phone radiation (900 MHz GSM signal) using two variants of human
endothelial cell line: EA.hy926 and EA.hy926v1. Gene expression changes were
examined in three experiments using cDNA Expression Arrays and protein
expression changes were examined in ten experiments using 2-DE and PDQuest
software. Obtained results show that gene and protein expression were altered,
in both examined cell lines, in response to one hour mobile phone radiation
exposure at an average specific absorption rate of 2.8 W/kg. However, the same
genes and proteins were differently affected by the exposure in each of the
cell lines. This suggests that the cell response to mobile phone radiation
might be genome- and proteome-dependent. Therefore, it is likely that different
types of cells and from different species might respond differently to mobile
phone radiation or might have different sensitivity to this weak stimulus. Our
findings might also explain, at least in part, the origin of discrepancies in
replication studies between different laboratories.
15
Philippova
TM, Novoselov VI, Alekseev SI, Influence of microwaves on different types of
receptors and the role of peroxidation of lipids on receptor-protein shedding. Bioelectromagnetics
15(3):183-192, 1994.
The effects of a continuous wave or
pulse-modulated, 900 MHz microwave field were studied by in vitro assays of rat
chemoreceptors. The pulsed field was modulated as rectangular waves at rates of
1, 6, 16, 32, 75, or 100 pps. The pulse-period to pulse-duration ratio was 5 in
all cases, and specific absorption rates (SARs) ranged from 0.5 to 18 W/kg.
Binding of ligands to cell membranes was differentially affected by exposure to
microwaves. For example, binding of H3-glutamic acid to hippocampal cells was
not altered by a 15 min exposure to a continuous wave field at 1 W/kg, but
binding of H3-dihydroalprenolol to liver-cell membranes of neonates underwent a
fivefold decrease under the same field conditions. This effect was not
dependent on modulation or on a change in the constant of stimulus-receptor
binding but depended on a shedding of the membrane's receptor elements into
solution. The magnitude of inhibition correlated with the oxygen concentration
in the exposed suspension. Antioxidants (dithiothreitol and ionol) inhibited
the shedding of receptor elements. The microwave exposure did not cause an
accumulation of products from the peroxidation of lipids (POL).
Ascorbate-dependent or non-enzymatic POL was not responsible for the
inhibition, and POL was not found in other model systems. However, enzymatic
POL mechanisms in localized areas of receptor binding remain a possibility.
16
Stopczyk D,
Gnitecki W, Buczynski A, Markuszewski L, Buczynski J. [Effect of electromagnetic field produced by
mobile phones on the activity of superoxide dismutase (SOD-1) and the level of
malonyldialdehyde (MDA)--in vitro study] Med Pr. 53(4):311-314, 2002.
[Article in Polish]
The aim of the study was to assess in vitro the effect of electromagnetic field
produced by mobile phones on the activity of superoxide dismutase (SOD-1) and
the level of malonyldialdehyde (MDA) in human blood platelets. The suspension
of blood platelets was exposed to the electromagnetic field with the frequency
of 900 MHz for 1, 3, 5, and 7 min. Our studies demonstrated that microwaves
produced by mobile phones significantly depleted SOD-1 activity after 1, 5, and
7 min of exposure and increased after 3 min in comparison with the control
test. There was a significant increase in the concentration of MDA after 1, 5,
and 7 min and decrease after 3 min of exposure as compared with the control
test. On the grounds of
our results we conclude that oxidative stress after exposure to microwaves may
be the reason for many adverse changes in cells and may cause a number of
systemic disturbances in the human body.
17
Tafforeau M, Verdus
M-C, Norris V, White G, Demarty M, Thellier M, Ripoll C. SIMS study of the
calcium-deprivation step related to epidermal meristem production induced in
flax by cold shock or radiation from a GSM telephone. J Trace Microprobe
Tech 20(4):611-623, 2002.
Exposing seedlings of the flax, Linum
usitatissimum L., to a variety of weak environmental stresses plus a 2-day
calcium deprivation triggers the common response of production of epidermal
meristems in the hypocotyls. Here, we show that the same response was induced
by a 1 min cold shock. Epidemal meristem production was also induced by a
single 2-h exposure to radiation emitted at 0.9 GHz at non-thermal levels by a
GSM telephone. This flax-based system is
therefore well suited to studying the effects of low intensity stimuli,
including those of electromagnetic radiation.
To begin to determine the underlying mechanisms, in which calcium is
implicated, it is desirable to analyse the changes in ions in the tissues
affected. We therefore performed a Secondary Ion Mass Spectrometry (SIMS) study
of the distribution of the main inorganic cations in the hypocotl of control
and calcium-deprived seedlings. This showed decreases in calcium, sodium and
potassium and an increase in magnesium that did not alter substantially the
overall ratio of divalent to monovalent cations.
18
Baohong Wang, Jiliang H, Lifen J, Deqiang L, Wei Z, Jianlin L,
Hongping D. Studying the synergistic damage effects induced by 1.8GHz
radiofrequency field radiation (RFR) with four chemical mutagens on human
lymphocyte DNA using comet assay in vitro. Mutat Res. 2005 May 31; [Epub ahead of
print]
The aim of this investigation was to study the synergistic DNA damage effects
in human lymphocytes induced by 1.8GHz radiofrequency field radiation (RFR, SAR
of 3W/kg) with four chemical mutagens, i.e. mitomycin C (MMC, DNA crosslinker),
bleomycin (BLM, radiomimetic agent), methyl methanesulfonate (MMS, alkylating
agent), and 4-nitroquinoline-1-oxide (4NQO, UV-mimetic agent). The DNA damage
of lymphocytes exposed to RFR and/or with chemical mutagens was detected at two
incubation time (0 or 21h) after treatment with comet assay in vitro. Three
combinative exposure ways were used. Cells were exposed to RFR and chemical
mutagens for 2 and 3h, respectively. Tail length (TL) and tail moment (TM) were
utilized as DNA damage indexes. The results showed no difference of DNA damage
indexes between RFR group and control group at 0 and 21h incubation after
exposure (P>0.05). There were significant difference of DNA damage indexes
between MMC group and RFR+MMC co-exposure group at 0 and 21h incubation after
treatment (P<0.01). Also the significant difference of DNA damage indexes
between 4NQO group and RFR+4NQO co-exposure group at 0 and 21h incubation after
treatment was observed (P<0.05 or P<0.01). The DNA damage in RFR+BLM co-exposure
groups and RFR+MMS co-exposure groups was not significantly increased, as
compared with corresponding BLM and MMS groups (P>0.05). The experimental
results indicated 1.8GHz RFR (SAR, 3W/kg) for 2h did not induce the human
lymphocyte DNA damage effects in vitro, but could enhance the human lymphocyte
DNA damage effects induced by MMC and 4NQO. The synergistic DNA damage effects
of 1.8GHz RFR with BLM or MMS were not obvious.
19
Wolke S, Neibig U, Elsner R, Gollnick F, Meyer R,
Calcium homeostasis of isolated heart muscle cells exposed to pulsed
high-frequency electromagnetic fields. Bioelectromagnetics
17(2):144-153, 1996.
The intracellular calcium
concentration ([Ca(2+)]i) of isolated ventricular
cardiac myocytes
of the guinea pig was measured during the application of
pulsed
high-frequency electromagnetic fields. The high-frequency fields were
applied in a
transverse electromagnetic cell designed to allow microscopic
observation of
the myocytes during the presence of the high-frequency fields.
The [Ca(2+)]i was
measured as fura-2 fluorescence by means of digital image
analysis. Both
the carrier frequency and the square-wave pulse-modulation
pattern were
varied during the experiments (carrier frequencies: 900, 1,300,
and 1,800 MHz
pulse modulated at 217Hz with 14 percent duty cycle; pulsation
pattern at 900
MHz: continuous wave, 16 Hz, and 50 Hz modulation with 50
percent duty
cycle and 30 kHz modulation with 80 percent duty cycle). The mean
specific
absorption rate (SAR) values in the solution were within one order of
magnitude of 1 mW/kg. They varied depending on the
applied carrier frequency
and pulse
pattern. The experiments were designed in three phases: 500 s of sham exposure,
followed by 500 s of field exposure, then chemical stimulation
without field. The
chemical stimulation (K+ -depolarization) indicated the
viability of the
cells. The K+ depolarization yielded a significant increase in
[Ca(2+)]i.
Significant differences between sham exposure and high-frequency
field exposure
were not found except when a very small but statistically
significant
difference was detected in the case of 900 MHz/50 Hz. However, this
small difference
was not regarded as a relevant effect of the exposure.
20
Zmyslony M,
Politanski P, Rajkowska E, Szymczak W, Jajte J. Acute exposure to 930 MHz
CW electromagnetic radiation in vitro affects reactive oxygen species level in
rat lymphocytes treated by iron ions. Bioelectromagnetics. 25(5):324-328, 2004.
The aim of this study was to test the hypothesis that the 930 MHz continuous wave
(CW) electromagnetic field, which is the carrier of signals emitted by cellular
phones, affects the reactive oxygen species (ROS) level in living cells. Rat
lymphocytes were used in the experiments. A portion of the lymphocytes was
treated with iron ions to induce oxidative processes. Exposures to
electromagnetic radiation (power density 5 W/m2, theoretical calculated SAR =
1.5 W/kg) were performed within a GTEM cell. Intracellular ROS were measured by
the fluorescent probe dichlorofluorescin diacetate (DCF-DA). The results show
that acute (5 and 15 min) exposure does not affect the number of produced ROS.
If, however, FeCl2 with final concentration 10 microg/ml was added to the
lymphocyte suspensions to stimulate ROS production, after both durations of exposure,
the magnitude of fluorescence (ROS level during the experiment) was
significantly greater in the exposed lymphocytes. The character of the changes
in the number of free radicals observed in our experiments was qualitatively
compatible with the theoretical prediction from the model of electromagnetic
radiation effect on radical pairs.
21
Zotti-Martelli L, Peccatori
M, Maggini V, Ballardin M, Barale R.
Individual responsiveness
to induction of micronuclei in human lymphocytes after exposure in vitro to
1800-MHz microwave radiation. Mutat
Res. 582(1-2):42-52, 2005.
The widespread application
of microwaves is of great concern in view of possible consequences for human
health. Many in vitro studies have been carried out to detect possible effects
on DNA and chromatin structure following exposure to microwave radiation. The
aim of this study is to assess the capability of microwaves, at different power
densities and exposure times, to induce genotoxic effects as evaluated by the
in vitro micronucleus (MN) assay on peripheral blood lymphocytes from nine
different healthy donors, and to investigate also the possible inter-individual
response variability. Whole blood samples were exposed for 60, 120 and 180min
to continuous microwave radiation with a frequency of 1800MHz and power
densities of 5, 10 and 20mW/cm(2). Reproducibility was tested by repeating the
experiment 3 months later. Multivariate analysis showed that lymphocyte
proliferation indices were significantly different among donors (p<0.004) and
between experiments (p<0.01), whereas the applied power density and the
exposure time did not have any effect on them. Both spontaneous and induced MN
frequencies varied in a highly significant way among donors (p<0.009) and
between experiments (p<0.002), and a statistically significant increase of
MN, although rather low, was observed dependent on exposure time (p=0.0004) and
applied power density (p=0.0166). A considerable decrease in spontaneous and
induced MN frequencies was measured in the second experiment. The results show
that microwaves are able to induce MN in short-time exposures to medium power
density fields. Our data analysis highlights a wide inter-individual
variability in the response, which was confirmed to be a characteristic
reproducible trait by means of the second experiment.
Cellular damage
Balci M, Devrim E, Durak I. Effects of mobile phones on
oxidant/antioxidant balance in cornea and lens of rats. Curr Eye Res.
32(1):21-25, 2007.
Purpose: To investigate the effects of mobile-phone-emitted
radiation on the oxidant/antioxidant balance in corneal and lens tissues and to
observe any protective effects of vitamin C in this setting. Methods: Forty
female albino Wistar rats were assigned to one of four groups containing 10
rats each. One group received a standardized daily dose of mobile phone
radiation for 4 weeks. The second group received this same treatment along with
a daily oral dose of vitamin C (250 mg/kg). The third group received this dose
of vitamin C alone, while the fourth group received standard laboratory care
and served as a control. In corneal and lens tissues, malondialdehyde (MDA) levels
and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px),
and catalase (CAT) were measured with spectrophotometric methods. Results: In
corneal tissue, MDA level and CAT activity significantly increased in the
mobile phone group compared with the mobile phone plus vitamin C group and the
control group (p < 0.05), whereas SOD activity was significantly decreased
(p < 0.05). In the lens tissues, only the MDA level significantly increased
in the mobile phone group relative to mobile phone plus vitamin C group and the
control groups (p < 0.05). In lens tissue, significant differences were not
found between the groups in terms of SOD, GSH-Px, or CAT (p > 0.05).
Conclusions: The results of this study suggest that mobile telephone radiation
leads to oxidative stress in corneal and lens tissues and that antioxidants
such as vitamin C can help to prevent these effects
Belyaev IY, Koch CB, Terenius O, Roxstrom-Lindquist K, Malmgren LO, H Sommer W, Salford LG, Persson BR. Exposure
of rat brain to 915 MHz GSM microwaves induces changes in gene expression but
not double stranded DNA breaks or effects on chromatin conformation. Bioelectromagnetics.
2006 Mar 1; [Epub ahead of print]
We investigated whether exposure of rat brain to microwaves (MWs) of global
system for mobile communication (GSM) induces DNA breaks, changes in chromatin
conformation and in gene expression. An exposure installation was used based on
a test mobile phone employing a GSM signal at 915 MHz, all standard modulations
included, output power level in pulses 2 W, specific absorption rate (SAR) 0.4
mW/g. Rats were exposed or sham exposed to MWs during 2 h. After exposure, cell
suspensions were prepared from brain samples, as well as from spleen and
thymus. For analysis of gene expression patterns, total RNA was extracted from
cerebellum. Changes in chromatin conformation, which are indicative of stress
response and genotoxic effects, were measured by the method of anomalous
viscosity time dependencies (AVTD). DNA double strand breaks (DSBs) were
analyzed by pulsed-field gel electrophoresis (PFGE). Effects of MW exposure
were observed on neither conformation of chromatin nor DNA DSBs. Gene
expression profiles were obtained by Affymetrix U34 GeneChips representing 8800
rat genes and analyzed with the Affymetrix Microarray Suite (MAS) 5.0 software.
In cerebellum from all exposed animals, 11 genes were upregulated in a range of
1.34-2.74 fold and one gene was downregulated 0.48-fold (P < .0025). The
induced genes encode proteins with diverse functions including neurotransmitter
regulation, blood-brain barrier (BBB), and melatonin production. The data shows
that GSM MWs at 915 MHz did not induce PFGE-detectable DNA double stranded
breaks or changes in chromatin conformation, but affected expression of genes
in rat brain cells
Capri M, Scarcella E,
Fumelli C, Bianchi E, Salvioli S, Mesirca P, Agostini C, Antolini A, Schiavoni
A, Castellani G, Bersani F, Franceschi C. In vitro exposure of human lymphocytes to 900 MHz CW
and GSM modulated radiofrequency: studies of proliferation, apoptosis and
mitochondrial membrane potential. Radiat Res.
162(2):211-218, 2004a .
The aim of this study was to investigate the nonthermal effects of
radiofrequency (RF) fields on human immune cells exposed to a Global System for
Mobile Communication (GSM) signal generated by a commercial cellular phone and
by a sinusoidal non-modulated signal. To assess whether mobile phone RF-field
exposure affects human immune cell functions, peripheral blood mononuclear
cells (PBMCs) from healthy donors were exposed in vitro to a 900 MHz GSM or
continuous-wave (CW) RF field 1 h/day for 3 days in a transverse
electromagnetic mode (TEM) cell system (70-76 mW/kg average specific absorption
rate, SAR). The cells were cultured for 48 or 72 h, and the following end
points were studied: (1) mitogen-induced proliferation; (2) cell cycle
progression; (3) spontaneous and 2-deoxy-D-ribose (dRib)-induced apoptosis; (4)
mitochondrial membrane potential modifications during spontaneous and
dRib-induced-apoptosis. Data obtained from cells exposed to a GSM-modulated RF
field showed a slight decrease in cell proliferation when PBMCs were stimulated
with the lowest mitogen concentration and a slight increase in the number of
cells with altered distribution of phosphatidylserine across the membrane. On
the other hand, cell cycle phases, mitochondrial membrane potential and
susceptibility to apoptosis were found to be unaffected by the RF field. When
cells were exposed to a CW RF field, no significant modifications were observed
in comparison with sham-exposed cells for all the end points investigated.
Friedman J, Kraus S, Hauptman Y, Schiff Y, Seger R. Mechanism of a short-term ERK activation by
electromagnetic fields at mobile phone frequency. Biochem J. 2007
Apr 25; [Epub ahead of print]
The exposure to non-thermal
microwave electromagnetic field generated by mobile phones affects the
expression of many proteins. This effect on transcription and protein stability
can be mediated by the mitogen-activated protein kinase (MAPK) cascades, which
serve as central signaling pathways, and govern essentially all stimulated
cellular processes. Indeed, a long-term exposure of cells to mobile phone
irradiation results in the activation of p38MAPKs as well as the ERK/MAPKs.
Here we studied the immediate effect of irradiation on the MAPK cascades, and
found that ERKs, but not stress related MAPKs are rapidly activated in response
to various frequencies and intensities. Using signaling inhibitors we
delineated the mechanism that is involved in this activation. We found that the
first step is mediated in the plasma membrane by NADH oxidase, which rapidly
generates reactive oxygen species (ROS). These ROS then directly stimulate
matrix metalloproteinases and allow them to cleave and release heparin
binding-EGF. This secreted factor, activates EGF receptor, which in turn
further activates the ERK cascade. Thus, this study demonstrates for the first time a detailed molecular
mechanism by which electromagnetic irradiation by mobile phones induces the
activation of the ERK cascade and thereby induces transcription and other
cellular processes.
Mausset A, de
Seze R, Montpeyroux F, Privat A. Effects of radiofrequency
exposure on the GABAergic system in the rat cerebellum: clues from
semi-quantitative immunohistochemistry. Brain Res 912(1):33-46, 2001.
The widespread use of cellular phones raises the problem of interaction of
electromagnetic fields with the central nervous system (CNS). In order to
measure these effects on neurotransmitter content in the CNS, we developed a
protocol of neurotransmitter detection based on immunohistochemistry and image
analysis. Gamma-vinyl-GABA (GVG), an inhibitor of the GABA-transaminase was
injected in rats to increase GABA concentration in the CNS. The cellular GABA
contents were then revealed by immunohistochemistry and semi-quantified by
image analysis thanks to three parameters: optical density (O.D.), staining
area, and number of positive cells. The increase in cerebellar GABA content
induced by GVG 1200 mg/kg was reflected in these three parameters in the
molecular and the granular layers. Therefore, control of immunohistochemistry
parameters, together with appropriate image analysis, allowed both the location
and the detection of variations in cellular neurotransmitter content. This
protocol was used to investigate the effects of exposure to 900 MHz
radiofrequencies on cerebellar GABA content. Both pulsed emission with a
specific absorption rate (SAR) of 4 W/kg and continuous emission with high SAR
(32 W/kg) were tested. We observed a selective diminution of the stained
processes area in the Purkinje cell layer after exposure to pulsed
radiofrequency and, in addition, a decrease in O.D. in the three cell layers
after exposure to continuous waves. Whether this effect is, at least partly,
due to a local heating of the tissues is not known. Overall, it appears that
high energetic radiofrequency exposure induces a diminution in cellular GABA
content in the cerebellum.
Sarimov R, Malmgren L.O.G., Markova,
E., Persson,
B.R.R.. Belyaev,
I.Y. Nonthermal GSM microwaves affect chromatin
conformation in human lymphocytes similar to heat shock. IEEE Trans Plasma
Sci 32:1600-1608, 2004.
Here we investigated whether microwaves (MWs) of Global System for Mobile
Communication (GSM) induce changes in chromatin conformation in human
lymphocytes. Effects of MWs were studied at different frequencies in the range
of 895-915 MHz in experiments with lymphocytes from seven healthy persons.
Exposure was performed in transverse electromagnetic transmission line cell
(TEM-cell) using a GSM test-mobile phone. All standard modulations included 2 W
output power in the pulses, specific absorbed rate (SAR) being 5.4 mW/kg.
Changes in chromatin conformation, which are indicative of stress response and
genotoxic effects, were measured by the method of anomalous viscosity time
dependencies (AVTD). Heat shock and treatment with the genotoxic agent
camptothecin, were used as positive controls. 30-min exposure to MWs at 900 and
905 MHz resulted in statistically significant condensation of chromatin in
lymphocytes from 1 of 3 tested donors. This condensation was similar to effects
of heat shock within the temperature window of 40/spl deg/C-44/spl deg/C.
Analysis of pooled data from all donors showed statistically significant effect
of 30-min exposure to MWs. Stronger effects of MWs was found following 1-h
exposure. In replicated experiments, cells from four out of five donors
responded to 905 MHz. Responses to 915 MHz were observed in cells from 1 out of
5 donors, p<0.002. Dependent on donor, condensation, 3 donors, or
decondensation, 1 donor, of chromatin was found in response to 1-h exposure. Analysis
of pooled data from all donors showed statistically significant effect of 1-h
exposure to MWs. In cells from one donor, this effect was frequency-dependent
(p<0.01). Effects of MWs correlated statistically significantly with effects
of heat shock and initial state of chromatin before exposure. MWs at 895 and
915 MHz affected chromatin conformation in transformed lymphocytes. The
conclusion-GSM microwaves under specific conditions of exposure affected human
lymphocytes similar to stress response. The data suggested that the MW effects differ at
various GSM frequencies and vary between donors.
Velizarov, S, Raskmark, P, Kwee, S, The effects of
radiofrequency fields on cell proliferation are non-thermal. Bioelectrochem
Bioenerg 48(1):177-180, 1999.
The number of
reports on the effects induced by radiofrequency (RF) electromagnetic fields
and microwave (MW) radiation in various cellular systems is still increasing.
Until now no satisfactory mechanism has been proposed to explain the biological
effects of these fields. One of the current theories is that heat generation by
RF/MW is the cause, in spite of the fact that a great number of studies under
isothermal conditions have reported significant cellular changes after exposure
to RF/MW. Therefore, this study was undertaken to investigate which effect MW
radiation from these fields in combination with a significant change of
temperature could have on cell proliferation. The experiments were performed on
the same cell line, and with the same exposure system as in a previous work [S.
Kwee, P. Raskmark, Changes in cell proliferation due to environmental
non-ionizing radiation: 2. Microwave radiation, Bioelectrochem. Bioenerg., 44
(1998), pp. 251-255]. The field was generated by signal simulation of the
Global System for Mobile communications (GSM) of 960 MHz. Cell cultures,
growing in microtiter plates, were exposed in a specially constructed chamber,
a Transverse Electromagnetic (TEM) cell. The Specific Absorption Rate (SAR)
value for each cell well was calculated for this exposure system. However, in
this study the cells were exposed to
the field at a higher or lower temperature than the temperature in the
field-free incubator i.e., the temperature in the TEM cell was either 39 or 35
+/- 0.1 degrees C. The corresponding sham experiments were performed under
exactly the same experimental conditions. The results showed that there was a
significant change in cell proliferation in the exposed cells in comparison to
the non-exposed (control) cells at both temperatures. On the other hand, no
significant change in proliferation rate was found in the sham-exposed cells at
both temperatures. This shows that biological effects due to RF/MW cannot be
attributed only to a change of temperature. Since the RF/MW induced changes
were of the same order of magnitude at both temperatures and also comparable to
our previous results under isothermal conditions at 37 degrees C, cellular
stress caused by electromagnetic fields could initiate the changes in cell
cycle reaction rates. It is widely accepted that certain classes of heat-shock
proteins are involved in these stress reactions.
7. Cellular Damage and Cell
Death
DNA damage, Apoptosis
1
Gandhi G, Anita. Genetic damage in mobile phone
users: some preliminary findings. Ind J
Hum Genet 11(2): 99-104, 2005a.
BACKGROUND: The impact of microwave (MW)/radio
frequency radiation (RFR) on important biological parameters is probably more
than a simply thermal one. Exposure to radio frequency (RF) signals generated
by the use of cellular telephones have increased dramatically and reported to
affect physiological, neurological, cognitive and behavioural changes and to
induce, initiate and promote carcinogenesis. Genotoxicity of RFR has also been
reported in various test systems after in vitro and/or in vivo
exposure but none in mobile phone users.
AIMS: In the present study, DNA and chromosomal damage investigations
were carried out on the peripheral blood lymphocytes of individuals using
mobile phones, being exposed to MW frequency ranging from 800 to 2000 MHz.
METHODS: DNA damage was assessed using the single cell gel
electrophoresis assay and aneugenic and clastogenic damage by the in vivo
capillary blood micronucleus test (MNT) in a total of 24 mobile phone users.
RESULTS: Mean comet tail length (26.76 ± 0.054 mm; 39.75% of cells
damaged) in mobile phone users was highly significant from that in the control group. The in
vivo capillary blood MNT also revealed highly significant (0.25) frequency
of micronucleated (MNd) cells.
CONCLUSIONS: These results highlight a
correlation between mobile phone use (exposure to RFR) and genetic damage and
require interim public health actions in the wake of widespread use of mobile
telephony.
2
Belyaev IY,
Hillert L, Protopopova M, Tamm C, Malmgren LO, Persson BR, Selivanova G,
Harms-Ringdahl M. 915 MHz microwaves and 50 Hz magnetic field affect
chromatin conformation and 53BP1 foci in human lymphocytes from hypersensitive
and healthy persons. Bioelectromagnetics. 26(3):173-184, 2005.
We used exposure to microwaves from a global system for mobile communication
(GSM) mobile phone (915 MHz, specific absorption rate (SAR) 37 mW/kg) and power
frequency magnetic field (50 Hz, 15 muT peak value) to investigate the response
of lymphocytes from healthy subjects and from persons reporting
hypersensitivity to electromagnetic field (EMF). The hypersensitive and healthy
donors were matched by gender and age and the data were analyzed blind to
treatment condition. The changes in chromatin conformation were measured with
the method of anomalous viscosity time dependencies (AVTD). 53BP1 protein,
which has been shown to colocalize in foci with DNA double strand breaks
(DSBs), was analyzed by immunostaining in situ. Exposure at room temperature to
either 915 MHz or 50 Hz resulted in significant condensation of chromatin,
shown as AVTD changes, which was similar to the effect of heat shock at 41
degrees C. No significant differences in responses between normal and
hypersensitive subjects were detected. Neither 915 MHz nor 50 Hz exposure
induced 53BP1 foci. On the contrary, a distinct decrease in background level of
53BP1 signaling was observed upon these exposures as well as after heat shock
treatments. This decrease correlated with the AVTD data and may indicate
decrease in accessibility of 53BP1 to antibodies because of stress-induced
chromatin condensation. Apoptosis was determined by morphological changes and
by apoptotic fragmentation of DNA as analyzed by pulsed-field gel
electrophoresis (PFGE). No apoptosis was induced by exposure to 50 Hz and 915
MHz microwaves. In conclusion, 50 Hz magnetic field and 915 MHz microwaves
under specified conditions of exposure induced comparable responses in
lymphocytes from healthy and hypersensitive donors that were similar but not identical
to stress response induced by heat shock.
3
Caraglia M, Marra M, Mancinelli F, D'Ambrosio G, Massa R, Giordano A, Budillon A, Abbruzzese A, Bismuto E. Electromagnetic
fields at mobile phone frequency induce apoptosis and inactivation of the
multi-chaperone complex in human epidermoid cancer cells. J Cell Physiol. 204(2):539-548, 2005.
The exposure to non-thermal microwave electromagnetic field (MW-EMF) at 1.95
MHz, a frequency used in mobile communication, affects the refolding kinetics
of eukaryotic proteins (Mancinelli et al., 2004). On these basis we have
evaluated the in vivo effect of MW-EMF in human epidermoid cancer KB cells. We
have found that MW-EMF induces time-dependent apoptosis (45% after 3 h) that is
paralleled by an about 2.5-fold decrease of the expression of ras and Raf-1 and
of the activity of ras and Erk-1/2. Although also the expression of Akt was
reduced its activity was unchanged likely as a consequence of the increased
expression of its upstream activator PI3K. In the same experimental conditions
an about 2.5-fold increase of the ubiquitination of ras and Raf-1 was also
found and the addition for 12 h of proteasome inhibitor lactacystin at 10
microM caused an accumulation of the ubiquitinated isoforms of ras and Raf-1
and counteracted the effects of MW-EMF on ras and Raf-1 expression suggesting
an increased proteasome-dependent degradation induced by MW-EMF. The exposure
of KB cells to MW-EMF induced a differential activation of stress-dependent
pathway with an increase of JNK-1 activity and HSP70 and 27 expression and with
a reduction of p38 kinase activity and HSP90 expression. The overexpression of
HSP90 induced by transfection of KB cells with a plasmid encoding for the
factor completely antagonized the apoptosis and the inactivation of the ras -->
Erk-dependent survival signal induced by MW-EMF. Conversely, the inhibition of
Erk activity induced by 12 h exposure to 10 mM Mek-1 inhibitor U0126
antagonized the effects induced by HSP90 transfection on apoptosis caused by
MW-EMF. In conclusion, these results demonstrate for the first time that MW-EMF
induces apoptosis through the inactivation of the ras --> Erk survival
signaling due to enhanced degradation of ras and Raf-1 determined by decreased
expression of HSP90 and the consequent increase of proteasome dependent
degradation.
4
d'Ambrosio G, Massa R, Scarfi MR, Zeni O, Cytogenetic
damage in human lymphocytes following GMSK phase modulated microwave exposure. Bioelectromagnetics 23:7-13, 2002.
The present study
investigated, using in vitro experiments on human lymphocytes, whether exposure
to a microwave frequency used for mobile communication, either unmodulated or
in presence of phase only modulation, can cause modification of cell
proliferation kinetics and/or genotoxic effects, by evaluating the cytokinesis
block proliferation index and the micronucleus frequency. In the GSM 1800
mobile communication systems the field is both phase (Gaussian minimum shift
keying, GMSK) and amplitude (time domain multiple access, TDMA) modulated. The
present study investigated only the effects of phase modulation, and no
amplitude modulation was applied. Human peripheral blood cultures were exposed
to 1.748 GHz, either continuous wave (CW) or phase only modulated wave (GMSK),
for 15 min. The maximum specific absorption rate ( 5 W/kg) was higher than that occurring in the
head of mobile phone users; however, no changes were found in cell
proliferation kinetics after exposure to either CW or GMSK fields. As far as
genotoxicity is concerned, the micronucleus frequency result was not affected
by CW exposure; however, a statistically significant micronucleus effect was
found following exposure to phase modulated field. These results would suggest
a genotoxic power of the phase modulation per se.
5
Diem E,
Schwarz C, Adlkofer F, Jahn O, Rudiger H. Non-thermal DNA breakage by
mobile-phone radiation (1800MHz) in human fibroblasts and in transformed
GFSH-R17 rat granulosa cells in vitro. Mutat Res. 583:178-183, 2005.
Cultured human diploid fibroblasts and
cultured rat granulosa cells were exposed to intermittent and continuous
radiofrequency electromagnetic fields (RF-EMF) used in mobile phones, with
different specific absorption rates (SAR) and different mobile-phone
modulations. DNA strand breaks were determined by means of the alkaline and
neutral comet assay. RF-EMF exposure (1800MHz; SAR 1.2 or 2W/kg; different
modulations; during 4, 16 and 24h; intermittent 5min on/10min off or continuous
wave) induced DNA single- and double-strand breaks. Effects occurred after 16h
exposure in both cell types and after different mobile-phone modulations. The
intermittent exposure showed a stronger effect in the comet assay than
continuous exposure. Therefore
we conclude that the induced DNA damage cannot be based on thermal effects.
6
Ferreira AR, Knakievicz T, de Bittencourt
Pasquali MA, Gelain DP, Dal-Pizzol F, Fernandez CE, de Almeida de Salles
AA, Ferreira HB, Moreira JC. Ultra high frequency-electromagnetic field
irradiation during pregnancy leads to an increase in erythrocytes micronuclei
incidence in rat offspring. Life Sci. 2006
Aug 23; [Epub ahead of print]
Mobile telephones and their
base stations are an important ultra high frequency-electromagnetic field
(UHF-EMF) source and their utilization is increasing all over the world.
Epidemiological studies suggested that low energy UHF-EMF emitted from a
cellular telephone may cause biological effects, such as DNA damage and changes
on oxidative metabolism. An in vivo mammalian cytogenetic test, the
micronucleus (MN) assay, was used to investigate the occurrence of chromosomal
damage in erythrocytes from rat offspring exposed to a non-thermal UHF-EMF from
a cellular phone during their embryogenesis; the irradiated group showed a
significant increase in MN occurrence. In order to investigate if UHF-EMF could
also alter oxidative parameters in the peripheral blood and in the liver - an
important hematopoietic tissue in rat embryos and newborns - we also measured
the activity of antioxidant enzymes, quantified total sulfhydryl content,
protein carbonyl groups, thiobarbituric acid-reactive species and total
non-enzymatic antioxidant defense. No significant differences were found in any
oxidative parameter of offspring blood and liver. The average number of pups in
each litter has also not been significantly altered. Our results suggest that,
under our experimental conditions, UHF-EMF is able to induce a genotoxic
response in hematopoietic tissue during the embryogenesis through an unknown
mechanism.
7
Gadhia
PK, Shah T, Mistry A, Pithawala M, Tamakuwala D. A Preliminary Study to Assess
Possible Chromosomal Damage Among Users of Digital Mobile Phones. Electromag
Biol Med 22:149-159, 2003.
In a preliminary study to examine possible
lymphocyte chromosomal damage, we have tested two cytogenetic endpoints,
namely, chromosomal aberrations (CA) and sister chromatid exchange frequencies
(SCE), in 24 mobile phone users (12 nonsmoker-nonalcoholic subjects and 12
smoker-alcoholics), who used digital mobile phones for at least 2 years,
employing Gaussian Minimum Shift Keying modulations with uplink frequencies at
935-960 MHz. and downlinks at 890-915 MHz. For comparison, the control study
group included another 24 individuals, matched according to their age, sex,
drinking and smoking habits, as well as similar health status, working habits,
and professional careers; but did not use mobile phones. Blood samples of 12
mobile users (6 smoker-alcoholic and 6 nonsmoker-nonalcoholic) and 12 controls
(identical to mobile users in every respect) were further treated with a known
mutagen Mitomycin-C (MMC) to find out comutagenic/synergistic effect. A
complete blood picture for each individual was assessed with an automatic
particle cell counter.
There was a significant increase (P < 0.05)
in dicentric chromosomes among mobile users who were smoker-alcoholic as
compared to nonsmoker-nonalcoholic; the same held true for controls of both
types. After MMC treatment, there was a significant increase in dicentrics (P < 0.05)
and ring chromosomes (P < 0.001) in both smoker-alcoholic
and nonsmoker-nonalcoholic mobile users when compared with the controls.
Although SCEs showed a significant increase among mobile users, no change in
cell cycle progression was noted. The hematological picture showed only minor
variations between mobile users and controls.
8
Gandhi G, Singh P. Cytogenetic damage in mobile phone
users: preliminary data. Int J Hum Genet
5(4):259-265, 2005b.
Mobile
telephones, sometimes called cellular (cell) phones or handies, are now an
integral part of modern life. The mobile phone handsets are low-powered
radiofrequency transmitters, emitting maximum powers in the range of 0.2 to 0.6
watts. Scientific concenrns have increased sufficiently over the possible
hazard to health from using cell phones. The reported adverse health effects
include physiological, behavioural and cognitive changes as well as tumour formation
and genetic damage. However findings are controversial and no consensus exists.
Genotoxicity has been observed either in lower organisms or in vitro studies.
The aim of the present study hence was to detect any cytogenertic damage in
mobile phone users by analysing short term peripheral lymphocyte cultures for
chromosomal aberrations and the buccal mucosal cells for micronuclei
(aneugenicity and clastogenicity). The results revealed increased number of
micronucleated buccal cells and cytological abnormalities in cultured
lymphocytes indicating the
genotoxic response from mobile phone use.
9
Maes A, Collier M, Slaets D, Verschaeve L, 954 MHz
microwaves enhance the mutagenic properties of mitomycin C. Environ Mol
Mutagen 28(1):26-30, 1996.
This paper focuses on the combined effects of microwaves from mobile
communication frequencies and a chemical DNA damaging agent mitomycin C (MMC).
The investigation was performed in vitro by exposing whole blood samples to a
954 MHz emitting antenna from a GSM (Global System for Mobile Communication)
base station, followed by lymphocyte cultivation in the presence of MMC. A highly reproducible
synergistic effect was observed as based on the frequencies of sister
chromatid exchanges in metaphase figures.
10
Maes A, Collier M, Van Gorp U, Vandoninck S,
Verschaeve L, Cytogenetic effects of 935.2-MHz (GSM) microwaves alone and in
combination with mitomycin C. Mutat Res 393(1-2):151-156, 1997.
This paper
focuses on the genetic effects of microwaves from mobile communication
frequencies (935.2 MHz) alone and in combination with a chemical DNA-damaging
agent (mitomycin C). Three cytogenetic endpoints were investigated after in
vitro exposure of human whole blood cells. These endpoints were the 'classical'
chromosome aberration test, the sister chromatid exchange test and the alkaline
comet assay. No direct cytogenetic effect was found. The combined exposure of
the cells to the radiofrequency fields followed by their cultivation in the
presence of mitomycin C revealed a very weak effect when compared to cells
exposed to mitomycin C alone.
11
Marinelli F,
La Sala D, Cicciotti G, Cattini L, Trimarchi C, Putti S, Zamparelli A, Giuliani
L, Tomassetti G, Cinti C. Exposure to 900 MHz electromagnetic field induces an
unbalance between pro-apoptotic and pro-survival signals in T-lymphoblastoid
leukemia CCRF-CEM cells. J Cell Physiol. 198(2):324-332, 2004.
It has been recently established that low-frequency electromagnetic field
(EMFs) exposure induces biological changes and could be associated with
increased incidence of cancer, while the issue remains unresolved as to whether
high-frequency EMFs can have hazardous effect on health. Epidemiological
studies on association between childhood cancers, particularly leukemia and brain
cancer, and exposure to low- and high-frequency EMF suggested an etiological
role of EMFs in inducing adverse health effects. To investigate whether
exposure to high-frequency EMFs could affect in vitro cell survival, we
cultured acute T-lymphoblastoid leukemia cells (CCRF-CEM) in the presence of
unmodulated 900 MHz EMF, generated by a transverse electromagnetic (TEM) cell,
at various exposure times. We evaluated the effects of high-frequency EMF on
cell growth rate and apoptosis induction, by cell viability (MTT) test, FACS
analysis and DNA ladder, and we investigated pro-apoptotic and pro-survival
signaling pathways possibly involved as a function of exposure time by Western
blot analysis. At short exposure times (2-12 h), unmodulated 900 MHz EMF induced
DNA breaks and early activation of both p53-dependent and -independent
apoptotic pathways while longer continuous exposure (24-48 h) determined
silencing of pro-apoptotic signals and activation of genes involved in both
intracellular (Bcl-2) and extracellular (Ras and Akt1) pro-survival signaling.
Overall our results indicate that exposure to 900 MHz continuous wave, after
inducing an early self-defense response triggered by DNA damage, could confer
to the survivor CCRF-CEM cells a further advantage to survive and proliferate.
12
Mashevich
M, Folkman D, Kesar A, Barbul A, Korenstein R, Jerby E, Avivi L, Exposure of
human peripheral blood lymphocytes to electromagnetic fields associated with
cellular phones leads to chromosomal instability. Bioelectromagnetics
24:82-90, 2003.
Whether exposure
to radiation emitted from cellular phones poses a health hazard is at the focus
of current debate. We have examined whether in vitro exposure of human
peripheral blood lymphocytes (PBL) to continuous 830 MHz electromagnetic fields
causes losses and gains of chromosomes (aneuploidy), a major somatic mutation leading to genomic instability and thereby
to cancer. PBL were irradiated at different average absorption rates (SAR) in
the range of 1.6-8.8 W/kg for 72 hr in an exposure system based on a parallel
plate resonator at temperatures ranging from 34.5-37.5 °C. The averaged SAR and
its distribution in the exposed tissue culture flask were determined by
combining measurements and numerical analysis based on a finite element
simulation code. A linear increase in chromosome 17 aneuploidy was observed as
a function of the SAR value, demonstrating that this radiation has a genotoxic
effect. The SAR dependent aneuploidy was accompanied by an abnormal mode of
replication of the chromosome 17 region engaged in segregation (repetitive DNA
arrays associated with the centromere), suggesting that epigenetic alterations
are involved in the SAR dependent genetic toxicity. Control experiments (i.e.,
without any RF radiation) carried out in the temperature range of 34.5-38.5 °C
showed that elevated temperature is not associated with either the genetic or
epigenetic alterations observed following RF radiation - the
increased levels of aneuploidy and the modification in replication of the
centromeric DNA arrays. These
findings indicate that the genotoxic effect of the electromagnetic radiation is
elicited via a non-thermal pathway. Moreover, the fact that aneuploidy is a
phenomenon known to increase the risk for cancer, should be taken into
consideration in future evaluation of exposure guidelines.
13
Nikolova T, Czyz J, Rolletschek A, Blyszczuk P, Fuchs J, Jovtchev G, Schuderer J, Kuster N, Wobus AM. Electromagnetic
fields affect transcript levels of apoptosis-related genes in embryonic stem
cell-derived neural progenitor cells. ASEB J. 19(12):1686-1688, 2005.
Mouse embryonic stem (ES) cells were used as an experimental model to study the
effects of electromagnetic fields (EMF). ES-derived nestin-positive neural
progenitor cells were exposed to extremely low frequency EMF simulating power
line magnetic fields at 50 Hz (ELF-EMF) and to radiofrequency EMF simulating
the Global System for Mobile Communication (GSM) signals at 1.71 GHz (RF-EMF).
Following EMF exposure, cells were analyzed for transcript levels of cell cycle
regulatory, apoptosis-related, and neural-specific genes and proteins; changes
in proliferation; apoptosis; and cytogenetic effects. Quantitative RT-PCR
analysis revealed that ELF-EMF exposure to ES-derived neural cells
significantly affected transcript levels of the apoptosis-related bcl-2, bax,
and cell cycle regulatory "growth arrest DNA damage inducible" GADD45
genes, whereas mRNA levels of neural-specific genes were not affected. RF-EMF
exposure of neural progenitor cells resulted in down-regulation of
neural-specific Nurr1 and in up-regulation of bax and GADD45 mRNA levels.
Short-term RF-EMF exposure for 6 h, but not for 48 h, resulted in a low and
transient increase of DNA double-strand breaks. No effects of ELF- and RF-EMF
on mitochondrial function, nuclear apoptosis, cell proliferation, and chromosomal
alterations were observed. We may conclude that EMF exposure of ES-derived
neural progenitor cells transiently affects the transcript level of genes
related to apoptosis and cell cycle control. However, these responses are not
associated with detectable changes of cell physiology, suggesting compensatory
mechanisms at the translational and posttranslational level.
14
Pyrpasopoulou
A, Kotoula V, Cheva A, Hytiroglou P, Nikolakaki E, Magras IN, Xenos TD,
Tsiboukis TD, Karkavelas G. Bone morphogenetic protein expression in newborn rat
kidneys after prenatal exposure to radiofrequency radiation. Bioelectromagnetics 25(3):216-227, 2004.
Effects of nonthermal radiofrequency radiation (RFR) of the global system of
mobile communication (GSM) cellular phones have been as yet mostly studied at
the molecular level in the context of cellular stress and proliferation, as
well as neurotransmitter production and localization. In this study, a
simulation model was designed for the exposure of pregnant rats to pulsed GSM-like
RFR (9.4 GHz), based on the different resonant frequencies of man and rat. The
power density applied was 5 microW/cm2, in order to avoid thermal
electromagnetic effects as much as possible. Pregnant rats were exposed to RFR
during days 1-3 postcoitum (p.c.) (embryogenesis, pre-implantation) and days
4-7 p.c. (early organogenesis, peri-implantation). Relative expression and
localization of bone morphogenetic proteins (BMP) and their receptors (BMPR),
members of a molecular family currently considered as major endocrine and
autocrine morphogens and known to be involved in renal development, were
investigated in newborn kidneys from RFR exposed and sham irradiated (control)
rats. Semi-quantitative duplex RT-PCR for BMP-4, -7, BMPR-IA, -IB, and -II showed
increased BMP-4 and BMPR-IA, and decreased BMPR-II relative expression in
newborn kidneys. These changes were statistically significant for BMP-4,
BMPR-IA, and -II after exposure on days 1-3 p.c. (P <.001 each), and for
BMP-4 and BMPR-IA after exposure on days 4-7 p.c. (P <.001 and P =.005,
respectively). Immunohistochemistry and in situ hybridization (ISH) showed
aberrant expression and localization of these molecules at the histological
level. Our findings suggest that GSM-like RFR interferes with gene expression
during early gestation and results in aberrations of BMP expression in the
newborn. These molecular changes do not appear to affect renal organogenesis
and may reflect a delay in the development of this organ. The differences of
relative BMP expression after different time periods of exposure indicate the
importance of timing for GSM-like RFR effects on embryonic development.
15
Possible biological effects
of mobile phone microwaves were investigated in vitro. In this study, which was
part of the 5FP EU project REFLEX (Risk Evaluation of Potential Environmental
Hazards From Low-Energy Electromagnetic Field Exposure Using Sensitive in vitro
Methods), six human cell types, immortalized cell lines and primary cells, were
exposed to 900 and 1800 MHz. RNA was isolated from exposed and sham-exposed
cells and labeled for transcriptome analysis on whole-genome cDNA arrays. The
results were evaluated statistically using bioinformatics techniques and
examined for biological relevance with the help of different databases. NB69
neuroblastoma cells, T lymphocytes, and CHME5 microglial cells did not show
significant changes in gene expression. In EA.hy926 endothelial cells, U937
lymphoblastoma cells, and HL-60 leukemia cells we found between 12 and 34 up-
or down-regulated genes. Analysis of the affected gene families does not point
towards a stress response. However, following microwave exposure, some but not
all human cells might react with an increase in expression of genes encoding
ribosomal proteins and therefore up-regulating the cellular metabolism.
16
Sun LX, Yao K, He JL, Lu DQ, Wang KJ, Li HW. [Effect of acute exposure to microwave from mobile
phone on DNA damage and repair of cultured human lens epithelial cells in
vitro.] Zhonghua
Lao Dong Wei Sheng Zhi Ye Bing Za Zhi. 24(8):465-467, 2006.
[Article in Chinese]
OBJECTIVE: To investigate the
DNA damage of human lens epithelial cells (LECs) caused by acute exposure to
low-power 217 Hz modulated 1.8 GHz microwave radiation and DNA repair. METHODS:
Cultured LECs were exposed to 217 Hz modulated 1.8 GHz microwave radiation at
SAR (specific absorption rate) of 0, 1, 2, 3 and 4 W/kg for 2 hours in an
sXc-1800 incubator and irradiate system. The DNA single strand breaks were
detected with comet assay in sham-irradiated cells and irradiated cells
incubated for varying periods: 0, 30, 60, 120 and 240 min after irradiation.
Images of comets were digitized and analyzed using an Imagine-pro plus
software, and the indexes used in this study were tail length (TL) and tail
moment (TM). RESULTS: The difference in DNA-breaks between the exposure and
sham exposure groups induced by 1 and 2 W/kg irradiation was not significant at
every detect time (P > 0.05). As for the dosage of 3 and 4 W/kg there was
difference in both group immediately after irradiation (P < 0.01). At the
time of 30 min after irradiation the difference went on at both group (P <
0.01). However, the difference disappeared after one hour's incubation in 3
W/kg group (P > 0.05), and existed in 4 W/kg group. CONCLUSION: No or
repairable DNA damage was observed after 2 hour irradiation of 1.8 GHz
microwave on LECs when SAR </= 3 W/kg. The DNA damages caused by 4 W/kg irradiation were
irreversible.
17
Sun LX, Yao K, Jiang H, He JL, Lu DQ, Wang KJ, Li HW [DNA damage and
repair induced by acute exposure of microwave from mobile phone on cultured
human lens epithelial cells] Zhonghua
Yan Ke Za Zhi. 42(12):1084-1088, 2006..
[Article in
Chinese]
.OBJECTIVE: To investigate the effects of acute exposure of
low-power 217 Hz modulated 1. 8 GHz microwave radiation on the DNA damage of
human lens epithelial cells (hLECs) and repair. METHODS: Cultured hLECs were
exposed to 217 Hz modulated 1. 8 GHz microwave radiation at SAR (specific
absorption rate) of 1. 0, 2. 0, 3. O0 and 4. 0 W/kg for 2 hours in an sXc-1800
incubator and irradiate system, the DNA single strand breaks were detected with
comet assay ( single-cell gel electrophoresis) in sham-irradiated cells and
irradiated cells incubated for varying periods: 0, 30 and 60 minutes after
irradiation. Images of comets were digitized and analyzed using an Imagine-pro
plus software, and the indexes used in this study were tail length (TL) and
tail moment (TM). BrdU was added into the medium with additional one hour
incubation after radiation, the cell proliferation rate was determined using a
BrdU-kit. RESULTS: The difference of DNA-breaks between the exposure and sham
exposure groups induced by 1.0 and 2.0 W/kg irradiation were not significant in
each time points (P > 0.05) ; there were significant difference in both
groups at the exposure dose of 3. 0 and 4. 0 W/kg immediately and at the time
of 30 minutes after irradiation (P <0. 01) ; if the radiation exposure time
was beyond one hour no differences were be able to detected in 3.0 W/kg group
(P > 0. 05) compared with control, but the evidence of significant DNA
damage still existed in 4. 0 W/kg group at the same time point. Cell
proliferation rate had no significant difference when the application of SAR
was < or = 3. 0 W/kg (P >0. 05) , however the cell proliferation was
decreased significantly at the dose of 4. 0 W/kg irradiation ( P < 0. 01).
CONCLUSIONS: No effective DNA damage was induced using comet assay after 2
hours irradiation of 1. 8 GHz microwave on hLECs at the dose SAR < or = 3.0
W/kg. 4.0 W/kg irradiation caused significantly DNA damage and inhibition of
hLECs proliferation.
18
Sykes PJ,
McCallum BD, Bangay MJ, Hooker AM, Morley AA. Effect of Exposure to 900
MHz Radiofrequency Radiation on Intrachromosomal Recombination in pKZ1 Mice. Radiat Res 156(5):495-502, 2001.
Radiofrequency (RF) radiation emitted
from mobile phones is not considered to be directly genotoxic, but it may have
downstream effects on cellular DNA. We studied the effect of 4 W/kg pulsed 900
MHz RF radiation on somatic intrachromosomal recombination in the spleen in the
pKZ1 recombination mutagenesis model. Somatic intrachromosomal recombination
inversion events were detected in spleen tissue of pKZ1 mice by histochemical
staining for E. coli beta-galactosidase protein in cells in which the lacZ
transgene has undergone an inversion event. pKZ1 mice were exposed daily for 30
min to plane-wave fields of 900 MHz with a pulse repetition frequency of 217 Hz
and a pulse width of 0.6 ms for 1, 5 or 25 days. Three days after the last
exposure, spleen sections were screened for DNA inversion events. There was no
significant difference between the control and treated groups in the 1- and
5-day exposure groups, but there was a significant reduction in inversions
below the spontaneous frequency in the 25-day exposure group. This observation
suggests that exposure to RF radiation can lead to a perturbation in
recombination frequency which may have implications for recombination repair of
DNA. The biological significance of a reduction below the spontaneous frequency
is not known. The number of mice in each treatment group in this study was
small (n = 10 or n = 20). Therefore, repetition of this study with a larger
number of animals is required to confirm these observations.
19
Tice RR , Hook GG , Donner M
, McRee DI, Guy AW. Genotoxicity
of radiofrequency signals. I. Investigation of DNA damage and micronuclei
induction in cultured human blood cells. Bioelectromagnetics 23:113-126,
2002.
As part of a comprehensive investigation of
the potential genotoxicity of radiofrequency (RF) signals emitted by cellular
telephones, in vitro studies evaluated the induction of DNA and chromosomal
damage in human blood leukocytes and lymphocytes, respectively. The signals
were voice modulated 837 MHz produced by an analog signal generator or by a
time division multiple access (TDMA) cellular telephone, 837 MHz generated by a
code division multiple access (CDMA) cellular telephone (not voice modulated),
and voice modulated 1909.8 MHz generated by a global system of mobile
communication (GSM)-type personal communication systems (PCS) cellular
telephone. DNA damage (strand breaks/alkali labile sites) was assessed in
leukocytes using the alkaline (pH>13) single cell gel electrophoresis (SCG)
assay. Chromosomal damage was evaluated in lymphocytes mitogenically stimulated
to divide postexposure using the cytochalasin B-binucleate cell micronucleus
assay. Cells were exposed at 37±1°C, for 3 or 24 h at average specific
absorption rates (SARs) of 1.0-10.0 W/kg. Exposure for either 3 or 24 h did not
induce a significant increase in DNA damage in leukocytes, nor did exposure for 3 h induce a significant
increase in micronucleated cells among lymphocytes. However, exposure to each
of the four RF signal technologies for 24 h at an average SAR of 5.0 or 10.0
W/kg resulted in a significant and reproducible increase in the frequency of
micronucleated lymphocytes. The magnitude of the response (approximately four
fold) was independent of the technology, the presence or absence of voice
modulation, and the frequency (837 vs. 1909.8 MHz). This research demonstrates
that, under extended exposure conditions, RF signals at an average SAR of at
least 5.0 W/kg are capable of inducing chromosomal damage in human lymphocytes.
20
Zhang DY, Xu ZP, Chiang H, Lu DQ, Zeng QL. [Effects of GSM 1800 MHz
radiofrequency electromagnetic fields on DNA damage in Chinese hamster lung
cells.] Zhonghua
Yu Fang Yi Xue Za Zhi. 40(3):149-152, 2006.
[Article in Chinese]
OBJECTIVE: To study the effects of GSM 1800 MHz radiofrequency electromagnetic
fields (RF EMF) on DNA damage in Chinese hamster lung (CHL) cells. METHODS: The
cells were intermittently exposed or sham-exposed to GSM 1800 MHz RF EMF (5
minutes on/10 minutes off) at a special absorption rate (SAR) of 3.0 W/kg for 1
hour or 24 hours. Meanwhile, cells exposed to 2-acetaminofluorene, a DNA damage
agent, at a final concentration of 20 mg/L for 2 hours were used as positive
control. After exposure, cells were fixed by using 4% paraformaldehyde and
processed for phosphorylated form of H2AX (gammaH2AX) immunofluorescence
measurement. The primary antibody used for immunofluorescence was mouse
monoclonal antibody against gammaH2AX and the secondary antibody was
fluorescein isothiocyanate (FITC)-conjugated goat anti-mouse IgG. Nuclei were
counterstained with 4, 6-diamidino-2-phenylindole (DAPI). The gammaH2AX foci
and nuclei were visualized with an Olympus AX70 fluorescent microscope. Image
Pro-Plus software was used to count the gammaH2AX foci in each cell. For each
exposure condition, at least 50 cells were selected to detect gammaH2AX foci.
Cells were classified as positive when more than five foci were detected. The
percentage of gammaH2AX foci positive cells was adopted as the index of DNA
damage. RESULTS: The percentage of gammaH2AX foci positive cell of 1800 MHz RF EMF
exposure for 24 hours (37.9 +/- 8.6)% or 2-acetylaminofluorene exposure (50.9
+/- 9.4)% was significantly higher compared with the sham-exposure (28.0 +/-
8.4)%. However, there was no significant difference between the sham-exposure
and RF EMF exposure for 1 hour (31.8 +/- 8.7)%. CONCLUSION: 1800 MHz RF EMF
(SAR, 3.0 W/kg) for 24 hours might induce DNA damage in CHL cells.
21
Aksoy U, Sahin S, Ozkoc S, Ergor G. The effect of
electromagnetic waves on the growth of Entamoeba histolytica and Entamoeba
dispar. Saudi Med J.
26(9):1388-1390, 2005.
OBJECTIVE: The aim of this study was to investigate the influence of
electromagnetic radiation of a digital Global System for Mobile Communication
mobile telephone (900 MHz) on Entamoeba histolytica (E. histolytica) and
Entamoeba dispar (E. dispar) (cysts or trophozoites, or both) in a 24-hour
period. METHODS: This study was carried out from April 2004 to May 2004 at the
Department of Parasitology, Medical Faculty of Dokuz Eylul University in Izmir,
Turkey. The cultivated isolate tubes, which were exposed to electromagnetic
field at 37OC, were evaluated as study group, whereas the tubes without
exposure were assessed as control group. Finally, only living parasites in all
tubes were counted using a hemacytometer. The effect of the temperature was
evaluated for both control and study groups. RESULTS: The influence of electromagnetic
field and temperature was assessed separately for the study group. The parasite
number of E. histolytica decreased after exposure at 37OC and room temperature
(p=0.009) compared to the decrease in the control group (p=0.009). The parasite
number of E. dispar also decreased after exposure at 37OC and room temperature
(p=0.009). In comparison to control tubes, this was a significant decrease
(p=0.008). In the case of exposure of E. histolytica the results did not reveal
any significant difference between temperature degrees to magnetic field
(p=0.459) and E. dispar (p=0.172). CONCLUSION: Our findings show that exposure
to electromagnetic field for a certain period of time may cause damage that can
lead to death in single-cell organisms.
22
Markkanen A, Penttinen P, Naarala J, Pelkonen J,
Sihvonen A-P, Juutilainen J. Apoptosis induced by
ultraviolet radiation is enhanced by amplitude modulated radiofrequency
radiation in mutant yeast cells Bioelectromagnetics 25:127-133, 2004.
The aim of
this study was to investigate whether radiofrequency (RF) electromagnetic field
(EMF) exposure affects cell death processes of yeast cells. Saccharomyces
cerevisiae yeast cells of the strains KFy417 (wild-type) and KFy437
(cdc48-mutant) were exposed to 900 or 872 MHz RF fields, with or without
exposure to ultraviolet (UV) radiation, and incubated simultaneously with
elevated temperature (+37°C) to induce apoptosis in the cdc48-mutated strain.
The RF exposure was carried out in a special waveguide exposure chamber where
the temperature of the cell cultures can be precisely controlled. Apoptosis was
analyzed using the annexin V-FITC method utilizing flow cytometry. Amplitude
modulated (217 pulses per second) RF exposure significantly enhanced UV induced
apoptosis in cdc48-mutated cells, but no effect was observed in cells exposed
to unmodulated fields at identical time-average specfic absorption rates (SAR,
0.4 or 3.0 W/kg). The findings suggest that amplitude modulated RF fields,
together with known damaging agents, can affect the cell death process in
mutated yeast cells.
23
Panagopoulos DJ,
Chavdoula ED,
Nezis IP,
Margaritis LH
Cell death induced by GSM 900-MHz and DCS 1800-MHz mobile telephony radiation. Mutat Res. 2006
Oct 10; [Epub ahead of print] .
In the present study, the
TUNEL (Terminal deoxynucleotide transferase dUTP Nick End Labeling) assay - a
well known technique widely used for detecting fragmented DNA in various types of
cells - was used to detect cell death (DNA fragmentation) in a biological
model, the early and mid stages of oogenesis of the insect Drosophila
melanogaster. The flies were exposed in vivo to either GSM 900-MHz (Global
System for Mobile telecommunications) or DCS 1800-MHz (Digital Cellular System)
radiation from a common digital mobile phone, for few minutes per day during
the first 6 days of their adult life. The exposure conditions were similar to
those to which a mobile phone user is exposed, and were determined according to
previous studies of ours [D.J. Panagopoulos, A. Karabarbounis, L.H. Margaritis,
Effect of GSM 900-MHz mobile phone radiation on the reproductive capacity of D.
melanogaster, Electromagn. Biol. Med. 23 (1) (2004) 29-43; D.J. Panagopoulos,
N. Messini, A. Karabarbounis, A.L. Philippetis, L.H. Margaritis, Radio
frequency electromagnetic radiation within "safety levels" alters the
physiological function of insects, in: P. Kostarakis, P. Stavroulakis (Eds.),
Proceedings of the Millennium International Workshop on Biological Effects of
Electromagnetic Fields, Heraklion, Crete, Greece, October 17-20, 2000, pp.
169-175, ISBN: 960-86733-0-5; D.J. Panagopoulos, L.H. Margaritis, Effects of
electromagnetic fields on the reproductive capacity of D. melanogaster, in: P.
Stavroulakis (Ed.), Biological Effects of Electromagnetic Fields, Springer,
2003, pp. 545-578], which had shown a large decrease in the oviposition of the
same insect caused by GSM radiation. Our present results suggest that the decrease
in oviposition previously reported, is due to degeneration of large numbers of
egg chambers after DNA fragmentation of their constituent cells, induced by
both types of mobile telephony radiation. Induced cell death is recorded for
the first time, in all types of cells constituting an egg chamber (follicle
cells, nurse cells and the oocyte) and in all stages of the early and
mid-oogenesis, from germarium to stage 10, during which programmed cell death
does not physiologically occur. Germarium and stages 7-8 were found to be the
most sensitive developmental stages also in response to electromagnetic stress
induced by the GSM and DCS fields and, moreover, germarium was found to be even
more sensitive than stages 7-8.
8. Embryo Mortality
Grigor'ev IuG. [Biological effects of mobile phone
electromagnetic field on chick embryo (risk assessment using the mortality
rate)] Radiats Biol
Radioecol. 43(5):541-543,
2003.
[Article in Russian]
Chicken embryos were exposed to EMF from GSM mobile phone
during the embryonic development (21 days). As a result the embryo mortality
rate in the incubation period increased to 75% (versus 16% in control group).
9. Blood Brain Barrier
1
Salford LG, Brun A, Sturesson K, Eberhardt JL,
Persson BR Permeability of the blood-brain barrier induced by 915 MHz
electromagnetic radiation, continuous wave and modulated at 8, 16, 50, and 200
Hz. Microsc Res Tech 27(6):535-542, 1994.
Biological effects of electromagnetic fields (EMF) on the blood-brain barrier
(BBB) can be studied in sensitive and specific models. In a previous
investigation of the permeability of the blood-brain barrier after exposure to
the various EMF-components of proton magnetic resonance imaging (MRI), we found
that the exposure to MRI induced leakage of Evans Blue labeled proteins
normally not passing the BBB of rats [Salford et al. (1992), in: Resonance
Phenomena in Biology, Oxford University Press, pp. 87-91]. In the present
investigation we exposed male and female Fischer 344 rats in a transverse
electromagnetic transmission line chamber to microwaves of 915 MHz as
continuous wave (CW) and pulse-modulated with repetition rates of 8, 16, 50,
and 200 s-1. The specific energy absorption rate (SAR) varied between 0.016 and
5 W/kg. The rats were not anesthetized during the 2-hour exposure. All animals
were sacrificed by perfusion-fixation of the brains under chloral hydrate
anesthesia about 1 hour after the exposure. The brains were perfused with
saline for 3-4 minutes, and thereafter fixed in 4% formaldehyde for 5-6
minutes. Central coronal sections of the brains were dehydrated and embedded in
paraffin and sectioned at 5 microns. Albumin and fibrinogen were demonstrated
immunohistochemically. The results show albumin leakage in 5 of 62 of the
controls and in 56 of 184 of the animals exposed to 915 MHz microwaves.
Continuous wave resulted in 14 positive findings of 35, which differ
significantly from the controls (P = 0.002).
2
Salford LG,
Brun AR, Eberhardt JL, Malmgren L, Persson BRR, Nerve cell damage in mammalian
brain after exposure to microwaves from GSM mobile phones. Environ Health
Persp 111:881-883, 2003.
The possible
risks of radio-frequency electromagnetic fields for the human body is a growing
concern for the society. We have earlier shown that weak pulsed microwaves give
rise to a significant leakage of albumin through the blood-brain barrier (BBB).
Now we have investigated whether a pathological leakage over the BBB might be
combined with damage to the neurons. Three groups of each 8 rats were exposed
for 2 hours to GSM mobile phone electromagnetic fields of different strengths.
We found, and present here for the first time, highly significant (p< 0.002)
evidence for neuronal damage in both the cortex, the hippocampus and the basal
ganglia in the brains of exposed rats.
3
Schirmacher A, Winters S, Fischer
S, Goeke J, Galla H, Kullnick U, Ringelstein EB, Stogbauer F, Electromagnetic
fields (1.8 GHz) increase the permeability to sucrose of the blood-brain
barrier in vitro. Bioelectromagnetics
21(5):338-345, 2000.
We report an
investigation on the influence of high frequency electromagnetic
fields
(EMF) on the permeability of an in vitro model of the blood-brain barrier
(BBB). Our model was a co-culture consisting of rat astrocytes and porcine brain
capillary endothelial cells (BCEC). Samples were characterized morphologically
by scanning electron microscopy and immunocytochemistry. The BBB phenotype of
the BCEC was shown by the presence of zona occludens protein (ZO-1) as a marker
for tight junctions and the close contact of the cells together with the
absence of intercellular clefts. Permeability measurements using (14)C-sucrose
indicated a physiological tightness which correlated with the morphological
findings and verified the usefulness of our in vitro model. Samples were
exposed to EMF conforming to the GSM1800-standard used in mobile telephones
(1.8 GHz). The permeability of the samples was monitored over four days and
compared with results of samples that were cultured identically but not exposed
to EMF. Exposure to EMF increased permeability for (14)C-sucrose significantly
compared to unexposed samples. The underlying pathophysiological mechanism
remains to be investigated.
10. Brain Tumours
1
Hardell L, Mild KH, Carlsberg M. Case-control study on the use of cellular and
cordless phones and the risk for malignant brain tumours. Int. J. Radiat. Biol. 78:931-936, 2002.
Purpose: To investigate the use of cellular and cordless
phones and the risk for malignant brain tumours.
Materials and Methods: A case-control study was performed on
649 patents aged 20-80 years of both sexes with malignant brain tumour
diagnosed from 1 January 1997 to 30 June 2000. All patients were alive during
the time of the study and had histopathology verified brain tumours. One
matched control to each case was selected from the Swedish Population Register.
The study area was the Uppasala-Orebro, Stockholm, Linkoping and Goteborg
medical regions of Sweden.
Results: Exposure was assessed by a questionnaire answered
by 588 (91%) cases and 581 (90%) controls. Phone usage was defined as ‘ever
use' and usage starting 1 year before dagnosis was disregarded. Overall, no
significantly increased risks were found: analogue cellular phones yielded an
odds ratio (OR) =1.13, 95% confidence interval (CI) = 0.82-1.57, digital
cellular phones OR = 1.13, CI = 0.86-1.48, and cordless phones OR = 1.13, CI
=0.85-1.50. For ipsilateral (same side) radiofrequency exposure, analogue
mobile phones gave OR = 1.85, CI = 1.16-2.96, for all malignant brain tumours.
For astrocytoma, this risk was OR = 1.95, CI = 1.12-3.39. For all malignant brain tumours, digital
mobile phones yielded OR = 1.59, CI = 1.05-2.41, and cordless phones yielded OR
= 1.46, CI = 0.96-2.23, in the analysis of ipsilateral exposure.
Conclusion: The ipsilateral use of an analogue cellular phone yielded a
significantly increased risk for malignant brain tumours.
2
Hardell L, Hansson Mild K, Pahlson A, Hallquist A,
Ionizing radiation, cellular telephones and the risk of brain tumours. Europ J Cancer Prevent 10:523-529, 2001.
A case-control
study on brain tumours included 233 patients aged 20-80 years and alive at the
study time. They had histopathologically verified brain tumour and lived in the
Upsala-Orebro region (1994-1996) or in Stockholm region (1995-1996). Two
matched controls to each case were selected from the Swedish Population
Register. Two hundred and nine cases (90%) and 425 controls (91%) answered the
questionnaire. Results are presented for the whole study group, as given here,
and for malignant and benign tumours separately. For workers in the chemical
industry the odds ratio (OR) was 4.10, 95% confidence interval (95% CI)
1.25-13.4 and laboratory workers OR 3.21, 95%CI 1.16-8.85. Radiotherapy of the
head and neck region gave OR 3.61, 95% CI 0.65-19.9. Medical diagnostic X-ray
of the same area yielded OR 1.64, 95% CI 1.04-2.58. Work as a physician gave OR
6.00, 95% CI 0.62-57.7. All three cases
had worked with fluoroscopy. Ipsilateral (same side) use of a cellular telephone
increased the risk of tumours in the temporal, temporo-parietal and occipital
areas, with OR 2.42, 95% CI 0.97-6.05 (i.e., the anatomical areas with highest
exposure to microwaves from a mobile phone).
3
Hardell
L, Nasman A, Pahlson A, Hallquist A, Case-Control Study on Radiology Work,
Medical X-ray Investigations, and Use of Cellular Telephones as Risk Factors
for Brain Tumors.
Medscape General Medicine May 4, 2000.
Abstract
Context. Ionizing radiation is a well-established risk factor for brain tumors.
During recent years, microwave exposure from the use of cellular telephones has
been discussed as a potential risk factor.
Objective. To
determine risk factors for brain tumors.
Design. A case-control
study, with exposure assessed by questionnaires.
Participants. A total
of 233 currently living men and women, aged 20 to 80 years, were included. The
case patients had histopathologically verified brain tumors and lived in the
Uppsala-Orebro region (1994-1996) or the Stockholm region (1995-1996). Two
matched controls to each case were selected from the Swedish Population
Register.
Main Outcome Measures.
Ionizing radiation and use of cellular telephones as risk factors for brain
tumors.
Results. A total of
209 cases (90%) and 425 controls (91%) answered the questionnaire. Work as a
physician yielded an odds ratio (OR) of 6.00, with a 95% confidence interval
(CI) of 0.62 to 57.7. All three case patients had worked with fluoroscopy.
Radiotherapy of the head and neck region yielded an OR of 3.61 (95% CI,
0.65-19.9). Medical diagnostic x-ray examination of the same area yielded an OR
of 2.10 (95% CI, 1.25-3.53), with a tumor induction period of 5 years or more.
Chemical industry work yielded an OR of 4.10 (95% CI, 1.25-13.4), and
laboratory work yielded an OR of 3.21 (95% CI, 1.16-8.85). Ipsilateral use of
cellular telephones increased the risk for tumors in the temporal,
temporoparietal, and occipital lobes (OR, 2.42; 95% CI, 0.97-6.05), ie, the
anatomic areas with highest exposure to microwaves from a mobile telephone. The
result was further strengthened (OR, 2.62; 95% CI, 1.02-6.71) in a multivariate
analysis that included laboratory work and medical diagnostic x-ray
investigations of the head and neck.
Conclusion. Exposure
to ionizing radiation, work in laboratories, and work in the chemical industry
increased the risk of brain tumors. Use of a cellular telephone was associated
with an increased risk in the anatomic area with highest exposure.
4
Hardell L, Hallquist A, Hansson Mild K,
Carlberg M, Pahlson A, Lilja A. cellular and cordless telephones and the risk
for brain tumours. Europ J Cancer Prevent 11:377-386, 2002.
Microwave
exposure from the use of cellular telephones ahs been discussed in recently
years as a potential risk factor for brain tumours. We included in a
case-control study 1617 patients aged 20-80 years of both sexes with brain
tumour diagnosed between 1 January 1997 and 30 June 2000. They were alive at
the study time and had histopathologically verified brain tumour. One matched control
to each case was selected from the Swedish Population Register. The study area
was the Uppsala-Orebro, Stockholm, Linkoping and Goteborg medical regions of
Sweden. Exposure was assessed by a questionnaire that was answered by 1429
(88%) cases and 1470 (91%) controls. In total, use of analogue cellular
telephones gave an increased risk with an odds ratio (OR) of 1.3 (95%
confidence interval (CI) 1.02-1.6). With a tumour induction period of >10
years the risk increased further; OR 1.8 (95% CI 1.1-2.9). No clear association
was found for digital or cordless telephones. With regard to the anatomical
area of the tumour and exposure to microwaves, the risk was increased for
tumours located in the temporal area on the same side of the brain that was
used during phone calls; for analogue cellular telephones the OR was 2.5 (95%
CI 1.3-4.9). Use of a telephone on the opposite side of the brain was not
associated with an increased risk for brain tumours. With regard to different
tumour types, the highest risk was for acoustic neurinoma (OR 3.5, 95% CI
1.8-6.8) among analogue cellular telephone users.
5
Hardell
L, Mild KH, Carlberg M. Further
aspects on cellular and cordless telephones and brain tumours. Int J Oncol 22(2):399-407, 2003.
We included in a case-control study on brain tumours and mobile and cordless
telephones 1,617 patients aged 20-80 years of both sexes diagnosed during
January 1, 1997 to June 30, 2000. They were alive at the study time and had
histopathology verified brain tumour. One matched control to each case was
selected from the Swedish Population Register. The study area was the
Uppsala-Orebro, Stockholm, Linkoping and Goteborg medical regions of Sweden.
Exposure was assessed by a questionnaire that was answered by 1,429 (88%) cases
and 1,470 (91%) controls. In total use of analogue cellular telephones gave an
increased risk with odds ratio (OR)=1.3, 95% confidence interval (CI)=1.04-1.6,
whereas digital and cordless phones did not overall increase the risk
significantly. Ipsilateral use of analogue phones gave OR=1.7, 95% CI=1.2-2.3,
digital phones OR=1.3, 95% CI=1.02-1.8 and cordless phones OR=1.2, 95%
CI=0.9-1.6. The risk for ipsilateral use was significantly increased for
astrocytoma for all studied phone types, analogue phones OR=1.8,95% CI=1.1-3.2,
digital phones OR=1.8, 95% CI=1.1-2.8, cordless phones OR=1.8, 95% CI=1.1-2.9.
Use of a telephone on the opposite side of the brain was not associated with a
significantly increased risk for brain tumours. Regarding anatomical area of
the tumour and exposure to microwaves, the risk was increased for tumours
located in the temporal area on the same side of the brain that was used during
phone calls, significantly so for analogue cellular telephones OR=2.3, 95%
CI=1.2-4.1. For acoustic neurinoma OR=4.4, 95% CI=2.1-9.2 was calculated among
analogue cellular telephone users. When duration of use was analysed as a
continuous variable in the total material, the risk increased per year for
analogue phones with OR=1.04, 95% CI=1.01-1.08. For astrocytoma and ipsilateral
use the trend was for analogue phones OR=1.10, 95% CI=1.02-1.19, digital phones
OR=1.11, 95% CI=1.01-1.22, and cordless phones OR=1.09, 95% CI=1.01-1.19. There
was a tendency of a shorter tumour induction period for ipsilateral exposure to
microwaves than for contralateral, which may indicate a tumour promotor effect.
6
Hardell L,
Mild KH, Sandstrom M, Carlberg M, Hallquist A, Pahlson A. Vestibular
schwannoma, tinitus and cellular telephones. Neuroepidemiol 22:124-129,
2003.
Cases with tinnitus
after using analogue cellular telephones are presented. An increased odds radio
of 3.45, 95% confidence interval (CI) 1.77-6.76, was found for vestibular
schwannoma (VS) associated with the use of analogue cell phones. During the time period 1960-1998, the
age-standardized incidence of VS in Sweden significantly increased yearly by
+2.53% (CI 1.71-3.35). A significant increases in the incidence of VS was only
found for the latter of the two time period 1960-1979 and 1980-1998. For all
other brain tumors taken together, the incidence significantly increased yearly
by +0.80% (CI 0.59-1.02) for the time period 1960-1998, although the increase
was only significant for benign tumors other than VS during 1960-1979.
7
Hardell, L, Nasman, A, Pahlson, A, Hallquist, A,
Hansson Mild, K, Use of cellular telephones and the risk for brain tumours: A
case-control study. Int J Oncol 15(1):113-116, 1999.
The use of
cellular telephones has increased dramatically during the 1990's in the world.
In the 1980's the analogue NMT system was used whereas the digital GSM system
was introduced in early 1990's and is now the preferred system. Case reports of
brain tumours in users initiated this case-control study on brain tumours and
use of cellular telephones. Also other exposures were assessed. All cases, both
males and females, with histopathologically verified brain tumour living in
Uppsala-Orebro region (1994-96) and Stockholm region (1995-96) aged 20-80 at
the time of diagnosis and alive at start of the study were included, 233 in
total. Two controls to each case were selected from the Swedish Population
Register matched for sex, age and study region. Exposure was assessed by
questionnaires supplemented over the phone. The analyses were based on answers
from 209 (90%) cases and 425 (91%) controls. Use of cellular telephone gave
odds ratio (OR) = 0.98 with 95% confidence interval (CI) = 0. 69-1.41. For the
digital GSM system OR = 0.97, CI = 0.61-1.56 and for the analogue NMT system OR
= 0.94, CI = 0.62-1.44 were calculated. Dose-response analysis and using
different tumour induction periods gave similar results. Non-significantly
increased risk was found for tumour in the temporal or occipital lobe on the
same side as a cellular phone had been used, right side OR = 2.45, CI =
0.78-7.76, left side OR = 2.40, CI = 0.52-10.9 Increased risk was found only
for use of the NMT system. For GSM use the observation time is still too short
for definite conclusions. An increased risk for brain tumour in the anatomical
area close to the use of a cellular telephone should be especially studied in
the future.
8
Hardell L, Carlberg M, Hansson Mild K. Use of
cellular telephones and brain tumour risk in urban and rural areas. Occup Environ Med 62:390-394, 2005a.
Aim: To
investigate the association between the use of cellular or cordless telephones
and the risk for brain tumours in different geographical areas, urban and
rural.
Methods: patients
aged 20-80 years, living in the middle part of Sweden, and diagnosed between 1
January 1997 and 30 June 2000 were included. One control matched for sex and
age in five year age groups was selected for each case. Use of different phone
types was assessed by a questionnaire.
Results: The
number of participating cases was 1429; there were 1470 controls. An effect of
rural living was most pronounced for digital cellular telephones. Living in
rural areas yielded an odd ratio (OR) of 1.4 (95% CI 0.98 to 2.0), increasing
to 3.2 (95% CI 1.2 to 8.4) with > 5 year latency time for digital phones.
The corresponding Ors for living in urban areas were 0.9 (95% CI 0.8 to 1.2)
and 0.9 (95% CI 0.6 to 1.4), respectively. This effect was most obvious for
malignant brain tumours.
Conclusion: In
future studies, place of residence should be considered in assessment of exposure
to microwaves from cellular telephone, although the results in this study must
be interpreted with caution due to low numbers in some of the calculations.
9
Hardell L, Carlberg M, Hansson Mild K. Case-Control Study on Cellular and Cordless Telephones and the Risk for Acoustic Neuroma or Meningioma in Patients Diagnosed 2000-2003. Neuroepidemiology 25:120-128, 2005b.
We performed a
case-control study on the use of cellular and cordless telephones and the risk
for brain tumors. We report the results for benign brain tumors with data from
413 cases (89% response rate), 305 with meningioma, 84 with acoustic neuroma,
24 with other types and 692 controls (84% response rate). For meningioma,
analogue phones yielded odds ratio (OR) = 1.7, 95% confidence interval (CI) =
0.97-3.0, increasing to OR = 2.1, 95% CI = 1.1-4.3 with a >10-year latency
period. Also digital cellular phones and cordless phones increased the risk to
some extent. For acoustic neuroma, analogue phones gave OR = 4.2, 95% CI =
1.8-10 increasing to OR = 8.4, 95% CI = 1.6-45 with a >15-year latency
period, but based on low numbers. Digital phones yielded OR = 2.0, 95% CI =
1.05-3.8, whereas for cordless phones OR was not significantly increased. In
the multivariate analysis, analogue phones represented a significant risk
factor for acoustic neuroma.
10
Hardell, L., Carlberg, M., Mild, K.,
Case-control study of the association between the use of cellular and cordless
telephones and malignant brain tumors diagnosed during 2000-2003. Environmental Research. 100: 232-241, 2006a.
We performed a case-control study on the use of cellular and cordless
telephones and the risk for brain tumors diagnosed during 2000-2003. We report
the results for malignant brain tumors with data from 317 cases (88%) and 692
controls (84%). The use of analog cellular phones yielded odds ratio (OR) of
2.6 and a 95% confidence interval (CI) of 1.5-4.3, increasing to OR=3.5 and 95%
CI=2.0-6.4 with a >10-year latency period. Regarding digital cellular
telephones, the corresponding results were OR=1.9, 95% CI=1.3-2.7 and OR=3.6,
95% CI=1.7-7.5, respectively. Cordless telephones yielded OR=2.1, 95%
CI=1.4-3.0, and with a >10-year latency period, OR=2.9, 95% CI=1.6-5.2. The
OR increased with the cumulative number of hours of use and was highest for
high-grade astrocytoma. A somewhat increased risk was also found for low-grade
astrocytoma and other types of malignant brain tumors, although not
significantly so. In multivariate analysis, all three phone types studied
showed an increased risk.
11
Hardell L, Carlberg M, Hansson Mild K. Pooled analysis of two case-control studies on the use of cellular and
cordless telephones and the risk of benign brain tumours diagnosed during
1997-2003. Int J Oncol. 28(2):509-518, 2006b.
The use of cellular and cordless telephones and the risk of brain tumours is of
concern since the brain is a high exposure area. We present the results of a
pooled analysis of two case-control studies on benign brain tumours diagnosed
during 1997-2003 including answers from 1,254 (88%) cases and 2,162 (89%)
controls aged 20-80 years. For acoustic neuroma, the use of analogue cellular phones
gave an odds ratio (OR) of 2.9 and a 95% confidence interval (CI) of 2.0-4.3;
for digital cellular phones, OR=1.5; 95% CI=1.1-2.1; and for cordless
telephones, OR=1.5, 95% CI=1.04-2.0. The highest OR was found for analogue
phones with a latency period of >15 years; OR=3.8, 95% CI=1.4-10. Regarding
meningioma, the results were as follows: for analogue phones, OR=1.3, 95%
CI=0.99-1.7; for digital phones, OR=1.1, 95% CI=0.9-1.3; and for cordless
phones, OR=1.1, 95% CI=0.9-1.4. In the multivariate analysis, a significantly
increased risk of acoustic neuroma was found with the use of analogue phones.
12
Hardell LO, Carlberg M, Soderqvist F, Hansson Mild K, Morgan LL Long-term use of cellular phones and brain tumours -
increased risk associated with use for > 10 years. Occup
Environ Med. 2007 Apr 4; [Epub ahead of print]
AIM: To evaluate brain tumour
risk among long-term users of cellular telephones. METHODS: One cohort study
and 13 case-control studies were identified on this topic. Data were
scrutinized for use of mobile phone for > 10 years and ipsilateral exposure
if presented. RESULTS: The cohort study was of limit value due to
methodological shortcomings in the study. Of the 13 case-control studies, 9
gave results for > 10 years use or latency period. Most of these results
were based on low numbers. Clearly an association with acoustic neuroma was
found in four studies with two- to three-fold increased risk in the group with
at least 10 years use of a mobile phone. No risk was found in one study, but
the tumour size was significantly larger among users. Five studies gave results
for malignant brain tumours in that latency group. All gave increased OR
especially for ipsilateral exposure. Highest OR = 5.4, 95 % CI = 3.0-9.6 was
calculated for high-grade glioma and ipsilateral exposure in one study.
CONCLUSIONS: Results from present studies on use of mobile phones for > 10
years give a consistent pattern of an increased risk for acoustic neuroma and
glioma, most pronounced for high-grade glioma. The risk is highest for
ipsilateral exposure.
13
Lonn S, Ahlbom
A, Hall P, Feychting M. Mobile Phone Use and the Risk of Acoustic Neuroma. Epidemiology. 15(6):653-659, 2004.
BACKGROUND:: Radiofrequency exposure
from mobile phones is concentrated to the tissue closest to the handset, which
includes the auditory nerve. If this type of exposure increases tumor risk,
acoustic neuroma would be a potential concern. METHODS:: In this
population-based case-control study we identified all cases age 20 to 69 years
diagnosed with acoustic neuroma during 1999 to 2002 in certain parts of Sweden.
Controls were randomly selected from the study base, stratified on age, sex,
and residential area. Detailed information about mobile phone use and other environmental
exposures was collected from 148 (93%) cases and 604 (72%) controls. RESULTS::
The overall odds ratio for acoustic neuroma associated with regular mobile
phone use was 1.0 (95% confidence interval = 0.6-1.5). Ten years after the
start of mobile phone use the estimates relative risk increased to 1.9
(0.9-4.1); when restricting to tumors on the same side of the head as the phone
was normally used, the relative risk was 3.9 (1.6-9.5). CONCLUSIONS:: Our
findings do not indicate an increased risk of acoustic neuroma related to
short-term mobile phone use after a short latency period. However, our data
suggest an increased risk of acoustic neuroma associated with mobile phone use
of at least 10 years' duration.
14
Hansson Mild K, Hardell L, Carlberg M. Pooled analysis of two Swedish
case-control studies on the use of mobile and cordless telephones and the risk
of brain tumours diagnosed during 1997-2003. Int
J Occup Saf Ergon. 13(1):63-71, 2007.
Here we present the pooled
analysis of 2 case-control studies on the association of brain tumours with
mobile phone use. Use of analogue cellular phones increased the risk for
acoustic neuroma by 5%, 95% confidence interval (CI) = 2-9% per 100 hrs of use.
The risk increased for astrocytoma grade III-IV with latency period with
highest estimates using >10-year time period from first use of these phone
types. The risk increased per one year of use of analogue phones by 10%, 95% CI
= 6-14%, digital phones by 11%, 95% CI = 6-16%, and cordless phones by 8%, 95%
CI = 5-12%. For all studied phone types OR for brain tumours, mainly acoustic
neuroma and malignant brain tumours, increased with latency period, especially
for astrocytoma grade III-IV.
15
Muscat
JE, Malkin MG, Shore RE,. Thompson S, Neugut AL, Stellman
SD, Bruce J. Handheld cellular telephones and risk of acoustic
neuroma. Neurology 58:1304-1306, 2002.
The hypothesis that intracranial energy
deposition from handheld cellular telephones causes acoustic neuroma
was tested in an epidemiologic study of 90 patients and 86 control
subjects. The relative risk was 0.9 (p = 0.07) and did not
vary significantly by the frequency, duration, and lifetime hours of
use. In patients who used cellular telephones, the tumor occurred
more often on the contralateral than ipsilateral side of the head.
Further efforts should focus on potentially longer induction periods.
11. General Cancer
1
Repacholi, MH, Basten, A, Gebski, V, Noonan, D,
Finnie, J, Harris, AW, Lymphomas in E mu-Pim1 transgenic mice exposed to pulsed
900 MHZ electromagnetic fields. Radiat Res 147(5):631-640, 1997.
Whether
radiofrequency (RF) fields are carcinogenic is controversial; epidemiological
data have been inconclusive and animal tests limited. The aim of the present
study was to determine whether long-term exposure to pulse-modulated RF fields
similar to those used in digital mobile telecommunications would increase the
incidence of lymphoma in E mu-Pim1 transgenic mice, which are moderately
predisposed to develop lymphoma spontaneously. One hundred female E mu-Pim1
mice were sham-exposed and 101 were exposed for two 30-min periods per day for
up to 18 months to plane-wave fields of 900 MHz with a pulse repetition
frequency of 217 Hz and a pulse width of 0.6 ms. Incident power densities were
2.6-13 W/m2 and specific absorption rates were 0.008-4.2 W/kg, averaging
0.13-1.4 W/kg. Lymphoma risk was found to be significantly higher in the
exposed mice than in the controls (OR = 2.4. P = 0.006, 95% CI = 1.3-4.5).
Follicular lymphomas were the major contributor to the increased tumor
incidence. Thus long-term intermittent exposure to RF fields can enhance the
probability that mice carrying a lymphomagenic oncogene will develop lymphomas.
We suggest that such genetically cancer-prone mice provide an experimental
system for more detailed assessment of dose-response relationships for risk of
cancer after RF-field exposure.
2
Stang A, Anastassiou G,
Ahrens W, Bromen K, Bornfeld N, Jockel KH,
The possible role of radiofrequency radiation in the development of uveal
melanoma. Epidemiology 12(1):7-12, 2001.
There are few epidemiologic studies dealing with electromagnetic radiation and
uveal melanoma. The majority of these studies are exploratory and are based on
job and industry titles only. We conducted a hospital-based and
population-based case-control study of uveal melanoma and occupational exposures
to different sources of electromagnetic radiation, including radiofrequency
radiation. We then pooled these results. We interviewed a total of 118 female
and male cases with uveal melanoma and 475 controls matching on sex, age, and
study regions. Exposure to radiofrequency-transmitting devices was rated as (a)
no radiofrequency radiation exposure, (b) possible exposure to mobile phones,
or (c) probable/certain exposure to mobile phones. Exposures were rated
independently by two of the authors who did not know case or control status. We
used conditional logistic regression to calculate odds ratios (ORs) and 95%
confidence intervals (95% CIs). We found an elevated risk for exposure to radiofrequency-transmitting
devices (exposure to radio sets, OR = 3.0, 95% CI = 1.4-6.3; probable/certain
exposure to mobile phones, OR = 4.2, 95% CI = 1.2-14.5). Other sources
of electromagnetic radiation such as high-voltage lines, electrical machines,
complex electrical environments, visual display terminals, or radar units were
not associated with uveal melanoma. This is the first study describing an
association between radiofrequency radiation exposure and uveal melanoma.
Several methodologic limitations prevent our results from providing clear
evidence on the hypothesized association.
12. Immune response
1
Capri M, Salvioli S, Altilia S, Sevini F, Remondini D, Mesirca P, Bersani F, Monti D, Franceschi C Age-Dependent Effects of in Vitro
Radiofrequency Exposure (Mobile Phone) on CD95+ T Helper Human Lymphocytes. Ann N Y Acad Sci. 1067:493-499, 2006.
.Recent studies on "nonthermal" effects of mobile phone
radiofrequency (RF) suggest that RF can interact with cellular functions and
molecular pathways. To study the possible RF effects on human lymphocyte
activation, we analyzed CD25, CD95, CD28 molecules in unstimulated and
stimulated CD4+ e CD8+ T cells in vitro. Peripheral blood mononuclear cells
(PBMCs) from young and elderly donors were exposed or sham-exposed to RF (1,800
MHz, Specific Absorption Rate 2 W/kg) with or without mitogenic stimulation. No
significant changes in the percentage of these cell subsets were found between
exposed and sham-exposed lymphocytes in both young and elderly donors.
Nevertheless, after RF exposure we observed a slight, but significant,
downregulation of CD95 expression in stimulated CD4+ T lymphocytes from
elderly, but not from young donors. This age-related result is noteworthy given
the importance of such a molecule in
regulation of the immune response.
2
Stankiewicz W, Dąbrowski MP,
Kubacki R, Sobiczewska E, Szmigielski S
Immunotropic Influence of 900 MHz Microwave GSM Signal on Human Blood
Immune Cells Activated in Vitro. Electromagnetic Biology and Medicine
25(1) 45-51, 2006.
In an earlier
study we reported that Go phase peripheral blood mononulclear
cells (PBMC) exposed to low-level (SAR = 0.18 W/kg)
pulse-modulated 1300 MHz microwaves and subsequently cultured, demonstrate
changed immune activity (Dabrowski et al., 2003). We investigated whether
cultured immune cells induced into the active phases of cell cycle (G1,
S) and then exposed to microwaves will also be sensitive to electromagnetic
field. An anechoic chamber of our design containing a microplate with cultured
cells and an antenna emitting microwaves (900 MHz simulated GSM signal,
27 V/m, SAR 0.024 W/kg) was placed inside the ASSAB incubator. The
microcultures of PBMC exposed to microwaves demonstrated significantly higher
response to mitogens and higher immunogenic activity of monocytes (LM index)
than control cultures. LM index, described in detail elsewhere (Dabrowski et
al., 2001), represents the monokine influence on lymphocyte mitogenic response.
The results suggest that immune activity of responding lymphocytes and
monocytes can be additionally intensified by 900 MHz microwaves.
13. Effects on Melatonin
1
Burch
JB, Reif JS, Noonan CW, Ichinose T, Bachand AM, Koleber TL, Yost MG.
Melatonin metabolite excretion among cellular telephone users. Int J Rad
Biol 78: 1029-1036, 2002.
Abstract: Purpose: The relationship between cellular
telephone use and excretion of the melatonin metabolite 6-hydroxymelatonin
sulfate (6-OHMS) was evaluated in two populations of male electric utility
workers (Study 1, n=149; Study 2, n=77).
Materials and methods: Participants collected urine samples and recorded
cellular telephone use over 3 consecutive workdays. Personal 60-Hz magnetic
field (MF) and ambient light exposures were characterized on the same days
using EMDEX II meters. A repeated measures analysis was used to assess the
effects of cellular telephone use, alone and combined with MF exposures, after
adjustment for age, participation month and light exposure.
Results: No change in 6-OHMS excretion was observed among those with
daily cellular telephone use >25 min in Study 1 (5 worker-days). Study 2
workers with >25 min cellular telephone use per day (13 worker-days) had
lower creatinine-adjusted mean nocturnal 6-OHMS concentrations (p=0.05)
and overnight 6-OHMS excretion (p=0.03) compared with those without
cellular telephone use. There was also a linear trend of decreasing mean
nocturnal 6-OHMS/creatinine concentrations (p=0.02) and overnight 6-OHMS
excretion (p=0.08) across categories of increasing cellular telephone
use. A combined effect of cellular telephone use and occupational 60-Hz MF
exposure in reducing 6-OHMS excretion was also observed in Study 2.
Conclusions: Exposure-related reductions in 6-OHMS excretion were
observed in Study 2, where daily cellular telephone use of >25min was more
prevalent. Prolonged use of cellular telephones may lead to reduced melatonin
production, and elevated 60-Hz MF exposures may potentiate the effect.
2
Jarupat S, Kawabata A, Tokura H, Borkiewicz A. Effects of the
1900 MHz Electromagnetic Field Emitted from Cellular Phone on Nocturnal
Melatonin Secretion. J
Physiol Anthropol Appl Human Sci 22(1):61-63, 2003.
Exposure to
cellular phone EMF caused a significant reduction in salivary melatonin in
female human subjects.
3
Oktem F,
Ozguner F, Mollaoglu H, Koyu A, Uz E. Oxidative Damage in the Kidney Induced by
900-MHz-Emitted Mobile Phone: Protection by Melatonin. Arch Med Res. 36(4):350-355,
2005.
BACKGROUND: The mobile phones emitting 900-MHz electromagnetic radiation (EMR)
may be mainly absorbed by kidneys because they are often carried in belts.
Melatonin, the chief secretory product of the pineal gland, was recently found
to be a potent free radical scavenger and antioxidant. The aim of this study
was to examine 900-MHz mobile phone-induced oxidative stress that promotes
production of reactive oxygen species (ROS) on renal tubular damage and the
role of melatonin on kidney tissue against possible oxidative damage in rats.
METHODS: The animals were randomly grouped as follows: 1) sham-operated control
group and 2) study groups: i) 900-MHz EMR exposed (30 min/day for 10 days)
group and ii) 900-MHz EMR exposed+melatonin (100 mug kg(-1) s.c. before the
daily EMR exposure) treated group. Malondialdehyde (MDA), an index of lipid
peroxidation), and urine N-acetyl-beta-d-glucosaminidase (NAG), a marker of
renal tubular damage were used as markers of oxidative stress-induced renal
impairment. Superoxide dismutase (SOD), catalase (CAT), and glutathione
peroxidase (GSH-Px) activities were studied to evaluate the changes of
antioxidant status. RESULTS: In the EMR-exposed group, while tissue MDA and
urine NAG levels increased, SOD, CAT, and GSH-Px activities were reduced.
Melatonin treatment reversed these effects as well. In this study, the increase
in MDA levels of renal tissue and in urine NAG and also the decrease in renal
SOD, CAT, GSH-Px activities demonstrated the role of oxidative mechanism
induced by 900-MHz mobile phone exposure, and melatonin, via its free radical
scavenging and antioxidant properties, ameliorated oxidative tissue injury in
rat kidney. CONCLUSIONS: These results show that melatonin may exhibit a
protective effect on mobile phone-induced renal impairment in rats.
4
Oral B, Guney M, Ozguner F, Karahan N, Mungan T, Comlekci S, Cesur G. Endometrial Apoptosis Induced by a 900-MHz Mobile
Phone: Preventive Effects of Vitamins E and C. Adv Ther.
23(6):957-973, 2006.
Numerous reports have
described the effects induced by an electromagnetic field (EMF) in various
cellular systems. The purposes of this study were to examine oxidative stress
that promotes production of reactive oxygen species induced by a 900-megahertz (MHz)
mobile phone and the possible ameliorating effects of vitamins E and C on
endometrial tissue against EMF-induced endometrial impairment and apoptosis in
rats. Animals were randomly grouped as follows: (1) sham-operated control group
(n=8), (2) 900 MHz EMF-exposed group (n=8; 30 min/d for 30 d), and (3) 900 MHz
EMF-exposed group, treated with vitamins E and C (n=8; 50 mg/kg intramuscularly
and 20 mg/kg body weight intraperitoneally before daily EMF exposure).
Malondialdehyde (an index of lipid peroxidation) was used as a marker of
oxidative stress-induced endometrial impairment; Bcl-2, Bax, caspase-3, and
caspase-8 were assessed immunohistochemically. In this study, increased
malondialdehyde levels in endometrial tissue and apoptosis illustrated the role
of the oxidative mechanism induced by exposure to a 900-MHz mobile phone-like
device and vitamins E and C; via free radical scavenging and antioxidant
properties, oxidative tissue injury and apoptosis were ameliorated in rat
endometrium. In conclusion, exposure to 900-MHz radiation emitted by mobile
phones may cause endometrial apoptosis and oxidative stress, but treatment with
vitamins E and C can diminish these changes and may have a beneficial effect in
preventing endometrial changes in rats.
5
Ozguner F,
Aydin G, Mollaoglu H, Gokalp O, Koyu A, Cesur G. Prevention of mobile phone
induced skin tissue changes by melatonin in rat: an experimental study. Toxicol Ind Health.
20(6-10):133-139, 2004.
Most of the mobile phones in Turkey emit 900 MHz radiation which is mainly
absorbed by the skin and, to a lesser extent, muscle. The aim of this study was
to investigate the effects the 900 MHz electromagnetic irradiation emitted by
these devices on the induction of histopathologic changes in skin and the
effect of melatonin (Mel) on any of these changes. Thirty male Wistar-Albino
rats were used in the study. The experimental groups were composed of: a
nontreated control group, an irradiated group (IR) without Mel and an
irradiated with Mel treatment group (IR + Mel). 900 MHz radiation was applied
to IR group for 10 days (30 min/day). The IR + Mel group received 10 mg/kg per
day melatonin in tap water for 10 days before irradiation. At the end of the
tenth day, the skin graft was excized from the thoraco-abdominal area.
Histopathologic changes in skin were analyzed. In the IR group, increased
thickness of stratum corneum, atrophy of epidermis, papillamatosis, basal cell
proliferation, increased granular cell layer (hypergranulosis) in epidermis and
capillary proliferation, impairment in collagen tissue distribution and
separation of collagen bundles in dermis were all observed compared to the
control group. Most of these changes, except hypergranulosis, were prevented
with melatonin treatment. In conclusion, exposure to 900 MHz radiation emitted
by mobile phones caused mild skin changes. Furthermore, melatonin treatment can
reduce these changes and may have a beneficial effect to prevent 900 MHz mobile
phone-induced rat skin changes.
6
Ozguner F, Oktem F, Armagan A, Yilmaz R, Koyu A, Demirel R, Vural H, Uz E. Comparative
analysis of the protective effects of melatonin and caffeic acid phenethyl
ester (CAPE) on mobile phone-induced renal impairment in rat. Mol Cell Biochem. 276(1-2):31-37, 2005b.
Melatonin and caffeic acid phenethyl ester (CAPE), a component of honeybee
propolis, were recently found to be potent free radical scavengers and
antioxidants. There are a number of reports on the effects induced by
electromagnetic radiation (EMR) in various cellular systems. Mechanisms of
adverse effects of EMR indicate that reactive oxygen species may play a role in
the biological effects of this radiation. The present study was carried out to
compare the protective effects of melatonin and CAPE against 900 MHz EMR
emitted mobile phone-induced renal tubular injury. Melatonin was administered
whereas CAPE was given for 10 days before the exposure. Urinary
N-acetyl-beta-D-glucosaminidase (NAG, a marker of renal tubular injury) and
malondialdehyde (MDA, an index of lipid peroxidation), were used as markers of
oxidative stress-induced renal impairment in rats exposed to EMR. Superoxide
dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities
were studied to evaluate the changes of antioxidant status in renal tissue.
Urinary NAG and renal MDA were increased in EMR exposed rats while both
melatonin and CAPE caused a significant reduction in the levels of these
parameters. Likewise, renal SOD and GSH-Px activities were decreased in EMR
exposed animals while melatonin caused a significant increase in the activities
of these antioxidant enzymes but CAPE did not. Melatonin caused a significant
decrease in urinary NAG activity and MDA levels which were increased because of
EMR exposure. CAPE also reduced elevated MDA levels in EMR exposed renal
tissue, but the effect of melatonin was more potent than that of CAPE.
Furthermore, treatment of EMR exposed rats with melatonin increased activities
of SOD and GSH-Px to higher levels than those of control rats. In conclusion,
melatonin and CAPE prevent renal tubular injury by reducing oxidative stress
and protect the kidney from oxidative damage induced by 900 MHz mobile phone.
Nevertheless, melatonin seems to be a more potent antioxidant compared with
CAPE in kidney.
7
Ozguner F, Altinbas A, Ozaydin M, Dogan A, Vural H, Kisioglu AN, Cesur G, Yildirim NG. Mobile phone-induced myocardial oxidative stress: protection by a novel
antioxidant agent caffeic acid phenethyl ester. Toxicol Ind Health. 21(9):223-230, 2005c.
Electromagnetic radiation (EMR) or radiofrequency fields of cellular mobile
phones may affect biological systems by increasing free radicals, which appear
mainly to enhance lipid peroxidation, and by changing the antioxidant defense
systems of human tissues, thus leading to oxidative stress. Mobile phones are
used in close proximity to the heart, therefore 900 MHz EMR emitting mobile
phones may be absorbed by the heart. Caffeic acid phenethyl ester (CAPE), one
of the major components of honeybee propolis, was recently found to be a potent
free radical scavenger and antioxidant, and is used in folk medicine. The aim
of this study was to examine 900 MHz mobile phone-induced oxidative stress that
promotes production of reactive oxygen species (ROS) and the role of CAPE on
myocardial tissue against possible oxidative damage in rats. Thirty rats were
used in the study. Animals were randomly grouped as follows: sham-operated
control group (N: 10) and experimental groups: (a) group II: 900 MHz EMR
exposed group (N: 10); and (b) group III: 900 MHz EMR exposed+CAPE-treated
group (N: 10). A 900 MHz EMR radiation was applied to groups II and III 30
min/day, for 10 days using an experimental exposure device. Malondialdehyde
(MDA, an index of lipid peroxidation), and nitric oxide (NO, a marker of
oxidative stress) were used as markers of oxidative stress-induced heart
impairment. Superoxide dismutase (SOD), catalase (CAT), and glutathione
peroxidase (GSH-Px) activities were studied to evaluate the changes of
antioxidant status. In the EMR exposed group, while tissue MDA and NO levels
increased, SOD, CAT and GSH-Px activities were reduced. CAPE treatment in group
III reversed these effects. In this study, the increased levels of MDA and NO
and the decreased levels of myocardial SOD, CAT and GSH-Px activities
demonstrate the role of oxidative mechanisms in 900 MHz mobile phone-induced
heart tissue damage, and CAPE, via its free radical scavenging and antioxidant
properties, ameliorates oxidative heart injury. These results show that CAPE
exhibits a protective effect on mobile phone-induced and free radical mediated
oxidative heart impairment in rats.
8
Ozguner F, Bardak Y, Comlekci S. Protective effects of melatonin and caffeic acid phenethyl ester against
retinal oxidative stress in long-term use of mobile phone: A comparative study.
Mol Cell Biochem. 282(1-2):83-88, 2006.
There are numerous reports on the effects of electromagnetic radiation (EMR) in
various cellular systems. Melatonin and caffeic acid phenethyl ester (CAPE), a
component of honeybee propolis, were recently found to be potent free radical
scavengers and antioxidants. Mechanisms of adverse effects of EMR indicate that
reactive oxygen species may play a role in the biological effects of this
radiation. The present study was carried out to compare the efficacy of the
protective effects of melatonin and CAPE against retinal oxidative stress due
to long-term exposure to 900 MHz EMR emitting mobile phones. Melatonin and CAPE
were administered daily for 60 days to the rats prior to their EMR exposure
during our study. Nitric oxide (NO, an oxidant product) levels and
malondialdehyde (MDA, an index of lipid peroxidation), were used as markers of
retinal oxidative stress in rats following to use of EMR. Superoxide dismutase
(SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were
studied to evaluate the changes of antioxidant status in retinal tissue.
Retinal levels of NO and MDA increased in EMR exposed rats while both melatonin
and CAPE caused a significant reduction in the levels of NO and MDA. Likewise,
retinal SOD, GSH-Px and CAT activities decreased in EMR exposed animals while
melatonin and CAPE caused a significant increase in the activities of these
antioxidant enzymes. Treatment of EMR exposed rats with melatonin or CAPE
increased the activities of SOD, GSH-Px and CAT to higher levels than those of
control rats. In conclusion, melatonin and CAPE reduce retinal oxidative stress
after long-term exposure to 900 MHz emitting mobile phone. Nevertheless, there
was no statistically significant difference between the efficacies of these two
antioxidants against to EMR induced oxidative stress in rat retina. The
difference was in only GSH-Px activity in rat retina. Melatonin stimulated the
retinal GSH-Px activity more efficiently than CAPE did.
9
Wood A, Loughran
S, Stough C, Does evening exposure to mobile phone radiation affect
subsequent melatonin production? Int. J. Rad. Biol 82:69-76, 2006.
Purpose: To test
whether exposure to the emissions from a digital mobile phone handset prior to
sleep alters the secretion of melatonin. Materials and methods: In a
double-blind cross-over design, 55 adult volunteers were both actively exposed
or sham-exposed (in random order on successive Sunday nights) to mobile phone
emissions for 30 min (0.25 W average power). Urine collection
occurred immediately prior to retiring to bed and on rising the next morning.
Melatonin output was estimated from principal metabolite concentrations
(6-sulphatoxymelatonin (aMT6s) via radioimmunoassay), urine volumes and
creatinine concentrations. Results: Total melatonin metabolite output
(concentration×urine volume) was unchanged between the two exposure conditions
(active 14.1±1.1 µg; sham 14.6±1.3 µg). The pre- and post-bedtime
outputs considered separately were also not significantly different, although
the pre-bedtime value was less for active versus sham exposure. When melatonin
metabolite output was estimated from the ratio of aMT6s to creatinine
concentrations, the pre-bedtime value was significantly less ( p
= 0.037) for active compared to sham. Examination of individual
responses is suggestive of a small group of `responders'. Conclusions: Total
nighttime melatonin output is unchanged by mobile phone handset emissions, but
there could be an effect on melatonin onset time.
14. Sperm quality:
1
Agarwal A, Deepinder F, Sharma RK, Ranga G, Li J. Effect of cell phone usage on semen analysis in men
attending infertility clinic: an observational study. Fertil Steril.
2007 May 3; [Epub ahead of print]
OBJECTIVE: To investigate the
effect of cell phone use on various markers of semen quality. DESIGN:
Observational study. SETTING: Infertility clinic. PATIENT(S): Three hundred
sixty-one men undergoing infertility evaluation were divided into four groups
according to their active cell phone use: group A: no use; group B: <2
h/day; group C: 2-4 h/day; and group D: >4 h/day. INTERVENTION(S): None.
MAIN OUTCOME MEASURE(S): Sperm parameters (volume, liquefaction time, pH,
viscosity, sperm count, motility, viability, and morphology). RESULT(S): The
comparisons of mean sperm count, motility, viability, and normal morphology
among four different cell phone user groups were statistically significant.
Mean sperm motility, viability, and normal morphology were significantly
different in cell phone user groups within two sperm count groups. The
laboratory values of the above four sperm parameters decreased in all four cell
phone user groups as the duration of daily exposure to cell phones increased.
CONCLUSION(S): Use of cell phones decrease the semen quality in men by
decreasing the sperm count, motility, viability, and normal morphology. The
decrease in sperm parameters was dependent on the duration of daily exposure to
cell phones and independent of the initial semen quality.
2
Erogul O, Oztas E, Yildirim I, Kir T, Aydur E, Komesli G, Irkilata HC, Irmak MK, Peker AF. Effects of electromagnetic radiation from a cellular
phone on human sperm motility: an in vitro study. Arch Med Res.
37(7):840-843, 2006.
BACKGROUND: There has been
growing public concern on the effects of electromagnetic radiation (EMR)
emitted by cellular phones on human health. Many studies have recently been
published on this topic. However, possible consequences of the cellular phone usage
on human sperm parameters have not been investigated adequately. METHODS: A
total number of 27 males were enrolled in the study. The semen sample obtained
from each participant was divided equally into two parts. One of the specimens
was exposed to EMR emitted by an activated 900 MHz cellular phone, whereas the
other was not. The concentration and motility of the specimens were compared to
analyze the effects of EMR. Assessment of sperm movement in all specimens was
performed using four criteria: (A) rapid progressive, (B) slow progressive, (C)
nonprogressive, (D) no motility. RESULTS: Statistically significant changes
were observed in the rapid progressive, slow progressive and no-motility
categories of sperm movement. EMR exposure caused a subtle decrease in the
rapid progressive and slow progressive sperm movement. It also caused an
increase in the no-motility category of sperm movement. There was no
statistically significant difference in the sperm concentration between two
groups. CONCLUSIONS: These data suggest that EMR emitted by cellular phone
influences human sperm motility. In addition to these acute adverse effects of
EMR on sperm motility, long-term EMR exposure may lead to behavioral or
structural changes of the male germ cell. These effects may be observed later
in life, and they are to be investigated more seriously.
3
Fejes I, Za Vaczki Z, Szollosi J, Kolosza R S, Daru J, Kova Cs L, Pa L A Is there a
relationship between cell phone use and semen quality? Arch Androl. 51(5):385-393, 2005.
This study was conducted to determine a possible relationship between regular
cell phone use and different human semen attributes. The history-taking of men
in our university clinic was supplemented with questions concerning cell phone
use habits, including possession, daily standby position and daily transmission
times. Semen analyses were performed by conventional methods. Statistics were
calculated with SPSS statistical software. A total of 371 were included in the
study. The duration of possession and the daily transmission time correlated
negatively with the proportion of rapid progressive motile sperm (r = - 0.12 and
r = - 0.19, respectively), and positively with the proportion of slow
progressive motile sperm (r = 0.12 and r = 0.28, respectively). The low and
high transmitter groups also differed in the proportion of rapid progressive
motile sperm (48.7% vs. 40.6%). The prolonged use of cell phones may have
negative effects on the sperm motility characteristics.
4
Kilgallon SJ, Simmons LW. Image content influences
men's semen quality. Biol Lett 2005 (doi:10.1098/rsbl.2005.0324)
There is
increasing evidence from non-human animals that males adjust their ejaculation
expenditure according to the risk of sperm competition. In this study we show
that, after controlling for lifestyle factors known to influence semen quality,
human males viewing images depicting sperm competition had a higher percentage
of motile sperm in their ejaculates. Many lifestyle variables were confirmed to
influence semen quality, including the recent suggestion that storage of mobile
phones close to the testes can decrease semen quality.
15. Miscellaneous Studies:
1
Ayata A, Mollaoglu H, Yilmaz HR, Akturk O, Ozguner F,
Altuntas I. Oxidative stress-mediated skin damage in an experimental
mobile phone model can be prevented by melatonin. J Dermatol. 31(11):878-883, 2004.
Most mobile phones emit 900 MHz of radiation that is mainly absorbed by the
external organs. The effects of 900 MHz of radiation on fibrosis, lipid
peroxidation, and anti-oxidant enzymes and the ameliorating effects of
melatonin (Mel) were evaluated in rat skin. Thirty Wistar-Albino rats were used
in the study. The experimental groups were the control group, the irradiated
group (IR), and the irradiated+Mel treated group (IR+Mel). A dose of 900 MHz, 2
W radiation was applied to the IR group every day for 10 days (30 min/day). The
IR+Mel group received 10 mg/kg/day melatonin in tap water for 10 days before
the irradiation. At the end of the 10th day, a skin specimen was excised from
the thoracoabdominal area. The levels of malondialdehyde (MDA) and
hydroxypyroline and the activities of superoxide dismutase (SOD), glutathione
peroxidase (GSH-Px), and catalase (CAT) were studied in the skin samples. MDA
and hydroxyproline levels and activities of CAT and GSH-Px were increased
significantly in the IR group compared to the control group (p<0.05) and
decreased significantly in the IR+Mel group (p<0.05). SOD activity was
decreased significantly in the IR group and this decrease was not prevented by
the Mel treatment. These results suggest that rats irradiated with 900 MHz
suffer from increased fibrosis and lipid peroxidation (LPO). Mel treatment can
reduce the fibrosis and LPO caused by radiation.
2
Berg G, Spallek J, Schuz J, Schlehofer B, Bohler E, Schlaefer K, Hettinger I, Kunna-Grass K, Wahrendorf J, Blettner M. Occupational Exposure to Radio Frequency/Microwave
Radiation and the Risk of Brain Tumors: Interphone
It is still under debate whether
occupational exposure to radio frequency/microwave electromagnetic fields
(RF/MW-EMF) contributes to the development of brain tumors. This analysis
examined the role of occupational RF/MW-EMF exposure in the risk of glioma and
meningioma. A population-based, case-control study including 381 meningioma
cases, 366 glioma cases, and 1,494 controls aged 30-69 years was performed in
three German regions in 2000-2003. An exposure matrix for occupational activity
was constructed by using information on RF/MW-EMF exposure collected in a
computer-assisted personal interview. "High" exposure was defined as
an occupational exposure that may exceed the RF/MW-EMF exposure limits for the
general public recommended by the International Commission on Non-Ionizing
Radiation Protection. Multiple conditional logistic regressions were performed
separately for glioma and meningioma. No significant association between
occupational exposure to RF/MW-EMF and brain tumors was found. For glioma, the
adjusted odds ratio for highly exposed persons compared with persons not highly
exposed was 1.21 (95% confidence interval: 0.69, 2.13); for meningioma, it was
1.34 (95% confidence interval: 0.64, 2.81). However, the slight increase in
risk observed with increasing duration of exposure merits further research with
larger sample sizes.
3
Braune, S, Wrocklage, C, Raczek, J, Gailus, T,
Lucking, CH, Resting blood pressure increase during exposure to a
radio-frequency electromagnetic field. Lancet 351(9119):1857-1858,
1998.
Exposure of the right
hemisphere to a radiofrequency EMF for 35 min causes in human subjects an
increase in sympathetic efferent activity with increases the resting blood
pressure between 5-10 mm Hg. The effect is likely caused by vasoconstriction.
4
Forgacs Z, Somosy Z, Kubinyi G, Bakos J, Hudak A, Surjan A, Thuroczy G. Effect of whole-body 1800MHz GSM-like microwave exposure on testicular
steroidogenesis and histology in mice. Reprod Toxicol. 2006 Jan 21; [Epub ahead of
print]
The aim of our
study was to evaluate the possible effects of whole-body 1800MHz GSM-like
microwave exposure on male reproduction. After repeated exposure of mice to
microwaves at 0.018-0.023W/kg whole-body specific energy absorption rate (SAR)
an elevated serum testosterone level was measured, but no microwave exposure
related histopathological alteration could be detected in the reproductive
organs. The in vitro steroidogenic response of 48h Leydig cell cultures
obtained from exposed animals did not differ from the controls, suggesting that
Leydig cells were not the primary targets of the applied microwave exposure or
direct action of microwaves on Leydig cells was temporary only. In exposed
animals the red blood cell count and volume of packed red cells were also
increased. Further investigations are required to clarify the mechanism of
action of the applied microwave exposure on male mice, as well as to establish
the biological significance of the observed phenomena.
5
Grisanti G, Parlapiano C, Tamburello CC, Tine G,
Zanforlin L. Cellular phone effects on otoacoustic emissions. IEEE MTT-S Digest 2: 771-774, 1998.
A study on
bioelectromagnetic effects induced by the use of TACS phones, evidencing a
variation of the natural response of the auditory system is presented. This
study was performed applying a method based on the registration of the evoked
otoacosutic emissions (transient and distortion products). The experimental
results show that modulated electromagnetic fields modify the distortion
products in about all the examined subjects.
6
Hardell L, Eriksson M, Carlberg M, Sundstrom C, Mild KH. Use of
cellular or cordless telephones and the risk for non-Hodgkin's lymphoma. Int Arch Occup Environ Health. 2005c Jul
5;:1-8 [Epub ahead of print]
Objectives: To evaluate the use of cellular and cordless telephones as the risk
factor for non-Hodgkin's lymphoma (NHL). Methods: Male and female subjects aged
18-74 years living in Sweden were included during a period from 1 December 1999
to 30 April 2002. Controls were selected from the national population registry.
Exposure to different agents was assessed by questionnaire. Results: In total,
910 (91%) cases and 1016 (92%) controls participated. NHL of the B-cell type
was not associated with the use of cellular or cordless telephones. Regarding
T-cell NHL and >5 year latency period, the use of analogue cellular phones
yielded: odds ratio (OR) = 1.46, 95%; confidence interval (CI) = 0.58-3.70,
digital: OR=1.92, 95%; CI=0.77-4.80 and cordless phones: OR=2.47; CI=1.09-5.60.
The corresponding results for certain, e.g. cutaneous and leukaemia, T-cell
lymphoma for analogue phones were: OR=3.41, 95%; CI=0.78-15.0, digital:
OR=6.12, 95%; CI=1.26-29.7 and cordless phones: OR=5.48, 95%; CI=1.26-23.9.
Conclusions: The results indicate an association between T-cell NHL and the use
of cellular and cordless telephones, however based on low numbers and must be
interpreted with caution. Regarding B-cell NHL no association was found.
7
Kellenyi, L, Thuroczy, G, Faludy, B, Lenard, L,
Effects of mobile GSM radiotelephone exposure on the auditory brainstem
response (ABR). Neurobiology 7:79-81, 1999.
A 15-min
exposure to GSM phone radiation caused an increase in auditory brainstem
response in the exposed side of human subjects. Subjects also showed a hearing
deficiency in the high frequency range (20 dB hearing deficiency from 2 KHz to
10 KHz).
8
Kerekhanjanarong V, Supiyaphun P, Naratricoon J, Laungpitackchumpon P. The
effect of mobile phone to audiologic system. J Med
Assoc Thai. 2005 Sep;88 Suppl 4:S231-234.
Mobile phones have come into widespread use. There are a lot of possible
adverse effect to health. Use of mobile phone generate potentially harmful
radiofrequency electromagnetic field (EMF) particularly for the hearing aspect.
98 subjects underwent hearing evaluations at Department of Otolaryngology,
Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn
University. 31 males and 67females, mean age was 30.48 +/- 9.51 years old, all
subjects were investigated the hearing level by audiometry, tympanometry,
otoacoustic emission (OAE) and auditory brain stem evoked response (ABR). The
average of using time were 32.54 +/- 27.64 months, 57 subjects usually used the
right side and 41 the left side. Average time of use per day was 26.31 +/-
30.91 minutes (range from 3 to 180 mins). When the authors compared the
audiogram, both pure tone and speech audiometry, between the dominant and
nondominant side, it indicated that there is no significant different. When the
authors focused on the 8 subjects that used the mobile phone more than 60 mins
per day. It indicated that the hearing threshold of the dominant ears was worse
than the nondominant ears.
9
Khudnitskii, SS, Moshkarev, EA, Fomenko, TV, [On the
evaluation of the influence of cellular phones on their users]. [Article in
Russian] Med Tr Prom Ekol (9):20-24,
1999.
The authors
studied influence of ultrahigh frequency radiation caused by cellular phones on
functional state of central nervous, cardiovascular systems and local
temperature changes in cellular phones users. The head area near the phone
antenna appeared to be under the most intensive heating. Ultrahigh frequency
radiation induces significant changes in local temperature and in physiologic
parameters of central nervous and cardiovascular systems.
10
Kimata H. Enhancement of
allergic skin wheal responses by microwave radiation from mobile phones in
patients with atopic eczema/dermatitis syndrome. Int Arch Allergy Immunol 129(4):348-350, 2002.
Microwave radiation from mobile phones enhanced skin wheal responses induced by
house dust mite and Japanese cedar pollen while it had no effect on wheal
responses induced by histamine in patients with atopic eczema/dermatitis
syndrome (AEDS). Microwave radiation also increased plasma levels of substance
P (SP) and vasoactive intestinal peptide (VIP) in patients with AEDS. These
results indicate that microwave radiation from mobile phones may enhance
allergen-induced wheal responses in association with the release of SP and VIP.
This finding may be useful in elucidating the pathophysiology and treatment of
AEDS.
11
Kimata H.
Microwave radiation from cellular phones increases allergen-specific IgE
production. Allergy
60(6):838-839, 2005.
12
Monfrecola G,
Moffa G, Procaccini EM. Non-ionizing electromagnetic radiations, emitted by a
cellular phone, modify cutaneous blood flow. Dermatology. 207(1):10-14, 2003.
BACKGROUND: Our
surroundings are full of non-ionizing electromagnetic radiation (EMR) of
different frequency and power. The non-ionizing EMRs emitted by television,
computer and cellular phone (CF) sets have been increasing over the past few
years. OBJECTIVE: The aim of our study was to assess the effects of
non-ionizing EMRs (frequency 3 x 10(8) to 3 x 10(11) Hz), emitted by CFs, on
cutaneous blood flow in healthy volunteers. METHODS: Thirty healthy volunteers
(14 male and 16 female; age: 18-53 years) entered the study. Measurements of
cutaneous blood flow were taken under standard conditions (temperature and
humidity), using a laser Doppler He-Ne flowmeter that was applied to the ear
skin by an optical fibre probe. Microflow values were recorded without CF
contact with the skin (T0), with the CF turned off but in contact with the ear
skin (T1), with CF contact and turned on (T2), with CF contact, turned on and
receiving (T3). The microflow values were also recorded backwards: with CF
contact and set turned on (T4), with CF contact and turned off (T5), without CF
contact (T6). RESULTS: The mean value of basal microflow (T0), expressed as
perfusion units (PU), was 51.26+/-11.93 PU. During the T1 phase, the microflow
increase was 61.38%; in T2 it was 131.74%, in T3 157.67%, in T4 139.21% and in
T5 122.90%; in T6, the microflow value was 57.58+/-10 PU (similar to the basal
microflow). Statistically significant cutaneous microflow values (p<0.050)
were observed comparing the T1 to T5 values with basal microflow (T0).
Furthermore, in comparison with T1 values (CF turned off in contact with the
ear skin), the T2, T3 and T4 data were statistically significant (T2 vs. T1:
t=7.763 with p<0.050; T3 vs. T1: t=9.834 with p<0.050; T4 vs. T1: t=8.885
with p<0.050).
13
Nam KC, Kim SW, Kim SC, Kim DW.
Effects of RF exposure of teenagers and adults by CDMA cellular phones. Bioelectromagnetics.
27(7):509-514, 2006.
Many cellular phone provocation studies
have been conducted since the question of increased health risk from extended
usage of cellular phones became a social issue. Internationally, most studies
have been conducted regarding the effects of GSM cellular phones on blood
pressure and heart rate of adult volunteers. On the other hand, very few
provocation studies have been conducted regarding the physiological effects of
CDMA phones on teenagers. In this study, two volunteer groups consisting of 21
teenagers and 21 adults were exposed to 300 mW of radio frequency (RF)
electromagnetic field emitted by a CDMA cellular phone for half an hour.
Physiological parameters such as systolic and diastolic blood pressures, heart
rate, respiration rate, and skin resistance were simultaneously measured. All
the parameters for both groups were unaffected during the exposure except for
decreased skin resistance of the teenager group (P < .0001). For the
regrouped 23 male and 19 female subjects, all the parameters for both groups
were unaffected during the exposure except for decreased skin resistance of the
male subjects (P = .0026). Those resistances at 10 min after the terminated
exposure returned to the resistances at rest regardless of the different groups
of age and sex.
14
Oktay MF, Dasdag S. Effects of intensive and moderate
cellular phone use on hearing function. Electromagn Biol Med. 25(1):13-21, 2006.
The purpose of this study is to investigate the effects of radiation emitted by
mobile phones on the hearing of users. The study was carried out on three
groups: 1) 20 men who have used a cellular phone frequently and spoken
approximately 2 h per day for four years; 2) 20 men who have used a cellular
phone for 10-20 min per day for four years; and 3) 20 healthy men who have
never used a cellular phone (the control group). Brainstem evoked response
audiometric (BERA) and pure tone audiometric (PTA) methods were used to measure
the effects of exposure on hearing function of the subjects. In BERA
measurements, I-III, III-V, and I-V interpeak latencies were evaluated.
Interpeak latency of subjects in two experimental groups was compared to that
of subjects in the control group. The BERA results showed no differences among
the groups (p > 0.05).In PTA measurements, detection thresholds at 250 Hz,
500 Hz, 1000 Hz, 2000 Hz, 4000 Hz, and 8000 Hz frequencies were measured in all
three groups. No differences were observed between moderate mobile phone users
(10-20 min. per day) and control subjects. However, detection thresholds in
those who talked approximately 2 h per day were found to be higher than those
in either moderate users or control subjects. Differences at 4000 Hz for both
bone and air conduction for right ears, and 500 Hz, and 4000 Hz bone and air
conduction for left ears were significant for mean hearing threshold. This
study shows that a higher degree of hearing loss is associated with long-term
exposure to electromagnetic (EM) field generated by cellular phones.
15
Ozguner F, Oktem F, Ayata A, Koyu A, Yilmaz HR. A novel
antioxidant agent caffeic acid phenethyl ester prevents long-term mobile phone
exposure-induced renal impairment in rat. Prognostic value of malondialdehyde,
N-acetyl-beta-D-glucosaminidase and nitric oxide determination. Mol Cell Biochem. 277(1-2):73-80, 2005a.
Caffeic acid phenethyl ester (CAPE), a flavonoid like compound, is one of the
major components of honeybee propolis. It has been used in folk medicine for many
years in Middle East countries. It was found to be a potent free radical
scavenger and antioxidant recently. The aim of this study was to examine
long-term applied 900 MHz emitting mobile phone-induced oxidative stress that
promotes production of reactive oxygen species (ROS) and, was to investigate
the role of CAPE on kidney tissue against the possible electromagnetic
radiation (EMR)-induced renal impairment in rats. In particular, the ROS such
as superoxide and nitric oxide (NO) may contribute to the pathophysiology of
EMR-induced renal impairment. Malondialdehyde (MDA, an index of lipid
peroxidation) levels, urinary N-acetyl-beta-D: -glucosaminidase (NAG, a marker
of renal tubular injury) and nitric oxide (NO, an oxidant product) levels were
used as markers of oxidative stress-induced renal impairment and the success of
CAPE treatment. The activities of superoxide dismutase (SOD), catalase (CAT),
and glutathione peroxidase (GSH-Px) in renal tissue were determined to evaluate
the changes of antioxidant status. The rats used in the study were randomly
grouped (10 each) as follows: i) Control group (without stress and EMR), ii)
Sham-operated rats stayed without exposure to EMR (exposure device off), iii)
Rats exposed to 900 MHz EMR (EMR group), and iv) A 900 MHz EMR exposed + CAPE
treated group (EMR + CAPE group). In the EMR exposed group, while tissue MDA,
NO levels and urinary NAG levels increased (p < 0.0001), the activities of
SOD, CAT, and GSH-Px in renal tissue were reduced (p < 0.001). CAPE treatment
reversed these effects as well (p < 0.0001, p < 0.001 respectively). In
conclusion, the increase in NO and MDA levels of renal tissue, and in urinary
NAG with the decrease in renal SOD, CAT, GSH-Px activities demonstrate the role
of oxidative mechanisms in 900 MHz mobile phone-induced renal tissue damage,
and CAPE, via its free radical scavenging and antioxidant properties,
ameliorates oxidative renal damage. These results strongly suggest that CAPE
exhibits a protective effect on mobile phone-induced and free radical mediated
oxidative renal impairment in rats.
16
Pacini
S, Ruggiero M, Sardi I, Aterini S, Gulisano F, Gulisano M. Exposure to global system
for mobile communication (GSM) cellular phone radiofrequency alters gene
expression, proliferation, and morphology of human skin fibroblasts. Oncol Res 13(1):19-24, 2002.
Human skin fibroblasts were exposed to global system for mobile communication
(GSM) cellular phone radiofrequency for 1 h. GSM exposure induced alterations
in cell morphology and increased the expression of mitogenic signal
transduction genes (e.g., MAP kinase kinase 3, G2/mitotic-specific cyclin G1),
cell growth inhibitors (e.g., transforming growth factor-beta), and genes
controlling apoptosis (e.g., bax). A significant increase in DNA synthesis and
intracellular mitogenic second messenger formation matched the high expression
of MAP kinase family genes. These findings show that these electromagnetic
fields have significant biological effects on human skin fibroblasts.
17
Panagopoulos DJ, Karabarbounis A,
Margaritis LH. Effect of GSM 900-MHz mobile phone radiation on the reproductive
capacity of Drosophila melanogaster.
Electromag. Biol. Med. 23:29-43, 2004.
Pulsed radio frequency, (RF),
electromagnetic radiation from common GSM mobile phones, (Global System for
Mobile Telecommunications) with a carrier frequency at 900 MHz,
"modulated" by human voice, (speaking emission) decreases the reproductive
capacity of the insect Drosophila melanogaster by 50%-60%, whereas the
corresponding "nonmodulated" field (nonspeaking emission) decreases the
reproductive capacity by 15%-20%. The insects were exposed to the near field of
the mobile phone antenna for 6 min per day during the first 2-5 days of
their adult lives. The GSM field is found to affect both females and males. Our
results suggest that this field-radiation decreases the rate of cellular
processes during gonad development in insects.
18
Papageorgiou CC, Nanou ED, Tsiafakis VG, Kapareliotis E, Kontoangelos KA, Capsalis CN, Rabavilas AD, Soldatos CR. Acute
mobile phone effects on pre-attentive operation. Neurosci Lett.
2006 Jan 4; [Epub ahead of print]
There is a debate whether electromagnetic field (EMF) emitted by mobile phones
(MP) have an effect on cognitive functions. Since the auditory P50 component of
event-related potentials (ERPs) reflects pre-attentive processing and working
memory (WM) operation, the present study was designed to investigate whether the
exposure to MP-EMF affects the patterns of the P50 component of ERPs elicited
during a WM test. The P50 elicited during a WM task and evoked by two warning
stimuli low and high frequency (500 and 3000Hz) has been assessed in 19 normal
subjects (10 women and 9 men) both without and with exposure to a 900MHz
signal, emitted by a dipole antenna placed near the subjects. Results showed
that the presence of MP-EMFs induced statistically significant increase in the
amplitude of P50 evoked by the low frequency stimuli, at Fp1 and O1 electrode
leads as compared to themselves without MP-EMF exposure. In contrast the
exposure to MP-EMFs revealed statistically significant decrease of the
amplitude of P50 evoked by the high frequency stimuli, at Fp1 electrode lead as
compared to themselves without MP-EMF exposure. These findings provide evidence
that the MP-EMF emitted by mobile phone affect pre-attentive information
processing as it is reflected in P50 evoked potential. The basis of such an
effect is unclear, although several possibilities exist and call for potential
directions of future research.
19
Paredi P, Kharitonov SA, Hanazawa T, Barnes PJ, Local
vasodilator response to mobile phones. Laryngoscope 111(1):159-162, 2001.
OBJECTIVES: The use of mobile phones with the resulting generation of
potentially harmful electromagnetic fields (EMF) is the focus of public
interest. Heat generation and the activation of the inducible form of nitric
oxide (NO) synthase may be possible causes of the biological effects of EMF
exposure. We investigated if a mobile telephone conversation can modify skin
temperature, NO, and nasal resistance. METHODS: We studied the effect of an EMF
(900 MHz) generated by a commercially available cellular phone during a
30-minute telephone conversation on skin temperature, nasal NO measured by
chemiluminescence, and nasal minimal cross-sectional area (MCA) measured by
rhinometry. Eleven normal subjects (mean age +/- standard error of mean [SEM],
32 +/- 5 y; 10 male) were studied. RESULTS: There was a similar and significant
increase in skin temperature of the nostril and occipital area on the same side
as the telephone (maximal increase 2.3 +/- 0.2 degrees C at 6 min) as well as a
tendency for higher nasal NO levels (maximal increase 12.9 +/- 4.9% at 10 min),
whereas the MCA was significantly reduced (maximal decrease -27 +/- 6% at 15
min). Such changes were not recorded when an earpiece was used to avoid the
direct exposure to the electromagnetic field. There were no changes in the skin
temperature and nasal NO measured on the opposite side to the mobile phone,
whereas the MCA was significantly increased (38 +/- 10%). CONCLUSIONS: Exposure
to EMF produced by a mobile phone produces biological effects that can be
easily measured. Microwaves may increase skin temperature and therefore cause
vasodilation and reduce MCA. Further studies are needed to study the long-term
effects of mobile phone use and the relation among NO production, vasodilation,
and temperature.
20
Pavicic I, Trosic I, Sarolic A. Comparison of 864 MHz and 935 MHz microwave radiation effects on cell
culture. Arh
Hig Rada Toksikol. 57(2):149-154, 2006.
The objective of this study was to compare the effects of 864 MHz and 935 MHz
radiofrequency/microwave radiation on the ability of V79 cells to proliferate,
form colonies and on their viability. For one, two and three hours, the cells
were exposed to the 864 MHz field in a transversal electromagnetic mode cell
(TEM) connected with amplifier and to the 935 MHz field in a gigahertz
transversal electromagnetic mode cell (GTEM) equipped with a signal generator.
The average specific absorption rate (SAR) was 0.08 W kg(-1) for the 864 MHz
field and 0.12 W kg(-1) for the 935 MHz field. In comparison to the control
cell samples, the growth curve of the 864 MHz irradiated cells showed a
significant decrease after two-hour and three-hour exposure on the Day 3 after
exposure. Likewise, cells exposed to 935 MHz microwaves for three hours showed
a significant growth on Day 3 after exposure. The colony-forming ability and
viability of cells exposed to 864 MHz and 935 MHz microwaves did not
significantly differ from the matched controls. The applied RF/MW fields showed
a similar effect on cell culture growth, colony-forming ability and viability
of V79 cells.
21
Penafiel LM, Litovitz T, Krause D, Desta A, Mullins
JM, Role of modulation on the effect of microwaves on ornithine decarboxylase
activity in L929 cells. Bioelectromagnetics
18(2):132-141, 1997.
The effect of 835 MHz microwaves
on the activity of ornithine decarboxylase
(ODC) in L929
murine cell was investigated at an SAR of approximately 2.5 W/kg. The results
depended upon the type of modulation employed. AM frequencies of 16 Hz and 60
Hz produced a transient increase in ODC activity that reached a peak at 8 h of
exposure and returned to control levels after 24 h of exposure. In this case,
ODC was increased by a maximum of 90% relative to control levels. A 40%
increase in ODC activity was also observed after 8 h of exposure with a typical
signal from a TDMA digital cellular telephone operating in the middle of its
transmission frequency range (approximately 840 MHz). This signal was burst
modulated at 50 Hz, with approximately 30% duty cycle. By contrast, 8 h
exposure with 835 MHz microwaves amplitude modulated with speech produced no
significant change in ODC activity. Further investigations, with 8 h of
exposure to AM microwaves, as a function of modulation frequency, revealed that
the response is frequency dependent, decreasing sharply at 6 Hz an 600 Hz. Exposure
with 835 MHz microwaves, frequency modulated with a 60 Hz sinusoid, yielded no
significant enhancement in ODC activity for exposure times ranging between 2
and 24 h. Similarly, exposure with a typical signal from an AMPS analog
cellular telephone, which uses a form of frequency modulation, produced no
significant enhancement in ODC activity. Exposure with 835 MHz continuous wave
microwaves produced no effects for exposure times between 2 and 24 h, except
for a small but statistically significant enhancement in ODC activity after 6 h
of exposure. Comparison of these results suggests that effects are much more
robust when the modulation causes low-frequency periodic changes in the
amplitude of the microwave carrier.
22
Sanchez S, Milochau A, Ruffie G, Poulletier de Gannes F, Lagroye I, Haro E, Surleve-Bazeille JE, Billaudel B, Lassegues M, Veyret B. Human skin cell stress response to GSM-900 mobile
phone signals. FEBS J. 2006 Nov
9; [Epub ahead of print]
In recent years, possible
health hazards due to radiofrequency radiation (RFR) emitted by mobile phones
have been investigated. Because several publications have suggested that RFR is
stressful, we explored the potential biological effects of Global System for
Mobile phone communication at 900 MHz (GSM-900) exposure on cultures of
isolated human skin cells and human reconstructed epidermis (hRE) using human
keratinocytes. As cell stress markers, we studied Hsc70, Hsp27 and Hsp70 heat
shock protein (HSP) expression and epidermis thickness, as well as cell
proliferation and apoptosis. Cells were exposed to GSM-900 under optimal
culture conditions, for 48 h, using a specific absorption rate (SAR) of 2
W.kg(-1). This SAR level represents the recommended limit for local exposure to
a mobile phone. The various biological parameters were analysed immediately
after exposure. Apoptosis was not induced in isolated cells and there was no
alteration in hRE thickness or proliferation. No change in HSP expression was
observed in isolated keratinocytes. By contrast, a slight but significant increase
in Hsp70 expression was observed in hREs after 3 and 5 weeks of culture.
Moreover, fibroblasts showed a significant decrease in Hsc70, depending on the
culture conditions. These results suggest that adaptive cell behaviour in
response to RFR exposure, depending on the cell type and culture conditions, is
unlikely to have deleterious effects at the skin level.
23
Shallom JM, Di
Carlo AL, Ko D, Penafiel LM, Nakai A, Litovitz TA.
Microwave exposure induces Hsp70 and confers protection against hypoxia
in chick embryos. J
Cell Biochem
86(3):490-496, 2002.
To determine if microwave exposure could elicit a biological effect in the
absence of thermal stress, studies were designed in which chick embryos were
exposed to athermal microwave radiation (915 MHz) to look for induction of
Hsp70, a protein produced during times of cellular stress that aids in the
protection of cellular components. Levels of Hsp70 were found to increase
within 2 h, with maximum expression (approximately 30% higher than controls)
typically occurring by 3 h from the start of exposure. Other embryos were
exposed to microwave radiation prior to being subjected to hypoxic stress, and
were found to have significantly higher survival (P < 0.05) following
re-oxygenation than non-exposed controls. The results of these studies indicate
that not only can athermal microwave exposures activate the stress protein
response pathway; they can also enhance survivability following exposure to a
subsequent, potentially lethal stress. From a public health standpoint, it is
important that more studies be performed to determine if repeated exposures, a
condition likely to be found in cell phone use, are still beneficial.
24
Tkalec M,
Malaric K, Pevalek-Kozlina B. Influence of 400, 900, and 1900 MHz electromagnetic
fields on Lemna minor growth and peroxidase activity. Bioelectromagnetics. 26(3):185-193, 2005.
Increased use of radio and microwave
frequencies requires investigations of their effects on living organisms.
Duckweed (Lemna minor L.) has been commonly used as a model plant for
environmental monitoring. In the present study, duckweed growth and peroxidase
activity was evaluated after exposure in a Gigahertz Transversal
Electromagnetic (GTEM) cell to electric fields of frequencies 400, 900, and
1900 MHz. The growth of plants exposed for 2 h to the 23 V/m electric field of
900 MHz significantly decreased in comparison with the control, while an
electric field of the same strength but at 400 MHz did not have such effect. A
modulated field at 900 MHz strongly inhibited the growth, while at 400 MHz
modulation did not influence the growth significantly. At both frequencies a
longer exposure mostly decreased the growth and the highest electric field (390
V/m) strongly inhibited the growth. Exposure of plants to lower field strength
(10 V/m) for 14 h caused significant decrease at 400 and 1900 MHz while 900 MHz
did not influence the growth. Peroxidase activity in exposed plants varied,
depending on the exposure characteristics. Observed changes were mostly small,
except in plants exposed for 2 h to 41 V/m at 900 MHz where a significant
increase (41%) was found. Our results suggest that investigated electromagnetic
fields (EMFs) might influence plant growth and, to some extent, peroxidase
activity. However, the effects of EMFs strongly depended on the characteristics
of the field exposure.
16. Epidemiological Phone Mast Studies
1
Abdel-Rassoul G, El-Fateh OA, Salem MA, Michael A, Farahat F, El-Batanouny M, Salem E. Neurobehavioral effects among inhabitants around
mobile phone base stations. Neurotoxicology.
2006 Aug 1; [Epub ahead of print]
BACKGROUND: There is a
general concern on the possible hazardous health effects of exposure to
radiofrequency electromagnetic radiations (RFR) emitted from mobile phone base
station antennas on the human nervous system. AIM: To identify the possible
neurobehavioral deficits among inhabitants living nearby mobile phone base
stations. METHODS: A cross-sectional study was conducted on (85) inhabitants
living nearby the first mobile phone station antenna in Menoufiya governorate,
Egypt, 37 are living in a building under the station antenna while 48 opposite
the station. A control group (80) participants were matched with the exposed
for age, sex, occupation and educational level. All participants completed a
structured questionnaire containing: personal, educational and medical
histories; general and neurological examinations; neurobehavioral test battery
(NBTB) [involving tests for visuomotor speed, problem solving, attention and
memory]; in addition to Eysenck personality questionnaire (EPQ). RESULTS: The
prevalence of neuropsychiatric complaints as headache (23.5%), memory changes
(28.2%), dizziness (18.8%), tremors (9.4%), depressive symptoms (21.7%), and
sleep disturbance (23.5%) were significantly higher among exposed inhabitants
than controls: (10%), (5%), (5%), (0%), (8.8%) and (10%), respectively
(P<0.05). The NBTB indicated that the exposed inhabitants exhibited a
significantly lower performance than controls in one of the tests of attention
and short-term auditory memory [Paced Auditory Serial Addition Test (PASAT)].
Also, the inhabitants opposite the station exhibited a lower performance in the
problem solving test (block design) than those under the station. All
inhabitants exhibited a better performance in the two tests of visuomotor speed
(Digit symbol and Trailmaking B) and one test of attention (Trailmaking A) than
controls. The last available measures of RFR emitted from the first mobile
phone base station antennas in Menoufiya governorate were less than the
allowable standard level. CONCLUSIONS AND RECOMMENDATIONS: Inhabitants living
nearby mobile phone base stations are at risk for developing neuropsychiatric
problems and some changes in the performance of neurobehavioral functions
either by facilitation or inhibition. So, revision of standard guidelines for
public exposure to RER from mobile phone base station antennas and using of
NBTB for regular assessment and early detection of biological effects among
inhabitants around the stations are recommended.
Pub med: http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=16962663&dopt=AbstractPlus
2
Santini R, Santini P, Danze JM, Le Ruz P, Seigne
M.Study of the health of people living in the vicinity of mobile phone base
stations: I. Influence of distance and sex. Pathol Biol (Paris)
50(6):369-373, 2002.
[Article in French]
A survey study using questionnaire was conducted in 530 people (270 men, 260
women) living or not in vicinity of cellular phone base stations, on 18 Non
Specific Health Symptoms. Comparisons of complaints frequencies (CHI-SQUARE
test with Yates correction) in relation with distance from base station and
sex, show significant (p < 0.05) increase as compared to people living >
300 m or not exposed to base station, till 300 m for tiredness, 200 m for
headache, sleep disturbance, discomfort, etc. 100 m for irritability,
depression, loss of memory, dizziness, libido decrease, etc. Women
significantly more often than men (p < 0.05) complained of headache, nausea,
loss of appetite, sleep disturbance, depression, discomfort and visual
perturbations. This first study on symptoms experienced by people living in
vicinity of base stations shows that, in view of radioprotection, minimal
distance of people from cellular phone base stations should not be < 300 m.
3
Wolf R, Wolf D. Increased incidence of cancer near a
cell-phone transmitter station. Inter J
Cancer Prev 1(2):123-128, 2004.
Significant
concern has been raised about possible health effects from exposure to
radiofrequency (RF) electromagnetic fields, especially after the rapid
introduction of mobile telecommunication systems. Parents are especially
concerned with the possibility that children might develop cancer after
exposure to the RF emissions from mobile telephone base stations erected in or
near schools. The few epidemiologic studies that did report on cancer incidence
in relation to RF radiation have generally presented negative or inconsistent
results, and thus emphasized the need for more studies that should investigate
cohorts with high RF exposure for changes in cancer incidence. The aim of this
study is to investigate whether there is an increased cancer incidence in
populations, living in a small area, and exposed to RF radiation from a
cell-phone transmitter station.
This is an
epidemiologic assessment, to determine whether the incidence of cancer cases
among individuals exposed to a cell-phone transmitter station is different from
tat expected in Israel, in Netanya, or as compared to people who lived in a
nearby area. Participants are people (n=622) living in the area near a
cell-phone transmitter station for 3-7 years who were patients of one health
clinic (of DW). The exposure began 1 year before the start of the study when
the station first came into service. A second cohort of individuals (n=1222)
who get their medical services in a clinic located nearby with very closely
matched, environment, workplace and occupational characteristics was used for
comparison.
In the area of
exposure (area) eight cases of different kinds of cancer were diagnosed in a
period of only one year. This rate of cancers was compared both with the rate
of 31 cases per 10,000 per year in the general population and the 2/1222 rate
recorded in the nearby clinic (area B). Relative cancer rates for female were
10.5 for area A. 0.6 for area B and 1 for the whole town of Netanya. Cancer
incidence of women in area A was thus significantly higher (p<0.0001)
compared with that of area B and the whole city. A comparison of the relative risk revealed that there
were 4.15 times more cases in area than in the entire population.
The study indicates an association between increased
incidence of cancer and living in proximity to a cell-phone transmitter
station.
4
Navarro
EA, Segura J, Portolés M, Gómez-Perretta de Mateo C. The microwave syndrome: a
preliminary study in Spain. Electromagn Biol Med. 2003;22:161-169.
Abstract
A health survey was carried out in La Ñora,
Murcia, Spain, in the vicinity of two GSM 900/1800 MHz cellular phone base
stations. The E-field (~ 400 MHz - 3 GHz) measured in the bedroom was divided
in tertiles (0.02 - 0.04 / 0.05 - 0.22 / 0.25 - 1.29 V/m). Spectrum analysis
revealed the main contribution and variation for the E-field from the GSM base
station. The adjusted (sex, age, distance) logistic regression model showed
statistically significant positive exposure-response associations between the
E-field and the following variables: fatigue, irritability, headaches, nausea,
loss of appetite, sleeping disorder, depressive tendency, feeling of
discomfort, difficulty in concentration, loss of memory, visual disorder,
dizziness and cardiovascular problems. The inclusion of the distance, which
might be a proxy for the sometimes raised "concerns explanation", did
not alter the model substantially. These results support the first statistical
analysis based on two groups (arithmetic mean 0,65 V/m versus 0,2 V/m) as well
as the correlation coefficients between the E-field and the symptoms (Navarro
et al, "The Microwave Syndrome: A preliminary Study in Spain", Electromagnetic
Biology and Medicine, Volume 22, Issue 2, (2003): 161 - 169). Based on the
data of this study the advice would be to strive for levels not higher than 0.02
V/m for the sum total, which is equal to a power density of 0.0001 µW/cm²
or 1 µW/m², which is the indoor exposure value for GSM base stations
proposed on empirical evidence by the Public Health Office of the Government of
Salzburg in 2002.
5
Eger H. et al.,
Umwelt-Medizin-Gesellschaft. 2004-Nov;17 (4): 326-335
Einfluss der räumlichen Nähe von Mobilfunksendeanlagen auf die Krebsinzidenz (Influence
of the neighbourhood of a cellular transmitter antenna on the incidence of
cancer) (Influence de la proximité d'une antenne de transmission cellulaire sur
l'incidence du cancer)
[In
French]
Le
résultat de cette étude effectuée à NAILA en Allemagne montre que la proportion
de nouveaux cas de développement de cancer était significativement plus élevée
parmi les patients qui ont vécu les 10 dernières années à une distance jusqu'à
400 mètres des sites d'émetteurs cellulaires, qui ont été en opération depuis
1993, comparé aux patients qui vivaient plus loin, et que ces patients
tombaient malade en moyenne 8 ans plus tôt. Entre les années 1999 à 2004, après
5 ans d'opération de l'installation émettrice, le risque relatif de contracter un cancer a triplé pour les
résidents de l'aire à proximité de l'installation comparé aux habitants vivant
à Naila en dehors de cette aire.
Translation:
The
result of this study carried out with NAILA in Germany shows that the proportion
of new cases of development of cancer was significantly higher among the
patients who lived the 10 last years at a distance up to 400 meters of the
sites of cellular transmitters, which in operation since 1993, were compared to
the patients who lived further, and who these patients fell sick earlier on
average 8 years. Between the years 1999 to 2004, after 5 years of operation of
the transmitting installation, the relative risk to contract a cancer has triplet for the residents
of the surface near the installation compared to the inhabitants living with
Naila apart from this surface.
6
Bortkiewicz
A, Zmyślony
M, Szyjkowska
A, Gadzicka
E.
Zakładu
Fizjologii Pracy i Ergonomii, Instytutu Medycyny Pracy im. prof. J. Nofera w
Lodzi.
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The problem of health effects of
electromagnetic fields (EMF) emitted by cellular phone base stations evokes
much interest in view of the fact that people living in their vicinity are
fated to continuous exposure to EMF. None of the studies carried out throughout
the world have revealed excessive values of standards adopted by the
International Commission on Non-Ionizing Radiation Protection (ICNIRP). A
questionnaire was used as a study tool. The results of the questionnaire survey
reveal that people living in the vicinity of base stations report various
complaints mostly of the circulatory system, but also of sleep disturbances,
irritability, depression, blurred vision, concentration difficulties, nausea,
lack of appetite, headache and vertigo. The performed studies showed the
relationship between the incidence of individual symptoms, the level of
exposure, and the distance between a residential area and a base station. This association was observed
in both groups of persons, those who linked their complaints with the presence
of the base station and those who did not notice such a relation.
Further studies, clinical and those based on questionnaires, are needed to
explain the background of reported complaints.
PubMedID: 15620045 [PubMed - indexed for
MEDLINE]
7
Hutter
HP, Moshammer
H, Wallner
P, Kundi
M.
Department
of Occupational and Social Health, Institute of Environment Health, Faculty of
Medicine, Universitiy of Vienna.
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OBJECTIVE: The controversy about health
risks of electromagnetic fields (EMF) has contributed in raising fears
concerning emissions from celltowers. The study was to examine whether or not
neighbours of celltowers are particularly concerned about adverse health
effects of mobile phones and their base stations. METHODS: Prior to information
delivered by medical doctors of the Institute of Environmental Health at public
hearings a questionnaire was handed out to participants asking for their
personal rating of several environmental health risks including those of mobile
telecommunication (n = 123, response rate approx. 48%). Medical students (n =
366) served as a contrast group. RESULTS: Participants rated health risk for
both, mobile phones and celltowers higher as students. A trend for higher
ratings was also seen with older subjects and female sex. The risk ratings of
both exposures correlated well with each other. The magnitude of the perceived
risks, however, resembled that of other ubiquitous exposures like traffic noise
and air pollution. CONCLUSION: Contrary to the claims of the telecommunication industry, opponents of
celltowers generally do not express unusual fears concerning electromagnetic
field exposure. The outcome of our study indicates that the risk rating is
comparable with other perceived common hazards of the civilised world.
It is hypothesised that offering information and participation to the concerned
population will be efficient in reducing exaggerated fears.
17. Phone masts' effects on animals
Demonstrating it's not all in the mind
1
Joris Everaert; Dirk Bauwens. A
Possible Effect of Electromagnetic Radiation from Mobile Phone Base Stations on
the Number of Breeding House Sparrows (Passer domesticus) . Electromagnetic Biology
and Medicine, Volume 26, Issue 1 January 2007 , pages 63 - 72
Abstract
A possible effect of long-term exposure to
low-intensity electromagnetic radiation from mobile phone (GSM) base stations
on the number of House Sparrows during the breeding season was studied in six
residential districts in Belgium. We sampled 150 point locations within the 6
areas to examine small-scale geographic variation in the number of House
Sparrow males and the strength of electromagnetic radiation from base stations.
Spatial variation in the number of House Sparrow males was negatively and
highly significantly related to the strength of electric fields from both the
900 and 1800 MHz downlink frequency bands and from the sum of these bands
(Chi2-tests and AIC-criteria, P < 0.001). This
negative relationship was highly similar within each of the six study areas,
despite differences among areas in both the number of birds and radiation
levels. Thus, our data show that fewer House Sparrow males were seen at
locations with relatively high electric field strength values of GSM base
stations and therefore
support the notion that long-term exposure to higher levels of radiation
negatively affects the abundance or behavior of House Sparrows in the wild.
2
Loscher W, Kas G, Extraordinary behavior disorders
in cows in proximity to transmission stations. Der Praktische Tierarz 79:437-444, 1998.
(Article in German)
In addition to reduction of
milk yield and increased health problems, behavioral abnormalities were
observed over a period of two years in a herd of diary cows maintained in close
proximity to a TV and cell phone transmitting antenna. Evaluation of possible
factors which could explain the abnormalities in the live stock did not
disclose any factors other than the high-frequency electromagnetic fields. An experiment in which a cow
with abnormal behavior was brought to a stable 20 km away from the antenna
resulted in a complete normalization of the cow within five days, whereas
symptoms returned when the cow was brought back to the stable nearby the
antenna. In view of the previous described effects of electromagnetic
fields, it might be possible that the observed abnormalities in cows are
related to electromagnetic field exposure. (power densities measured 0.02-7
mW/m2).
3
ALFONSO BALMORI1 AND ÖRJAN HALLBERG. The Urban
Decline of the House Sparrow (Passer domesticus): A Possible
Link with Electromagnetic Radiation
Abstract
During recent decades, there has been a marked decline of the house
sparrow
(Passer domesticus) population in the United Kingdom and in several
western
European countries. The aims of this study were to determine whether
the population
is also declining in Spain and to evaluate the hypothesis that
electromagnetic
radiation (microwaves) from phone antennae is correlated with the
decline in the
sparrow population.
Between October 2002 and May 2006, point transect sampling was
performed
at 30 points during 40 visits to Valladolid, Spain. At each point, we
carried out
counts of sparrows and measured the mean electric field strength
(radiofrequencies
and microwaves: 1MHz-3GHz range). Significant declines (P=0.0037) were
observed in the mean bird density over time, and significantly low bird
density was
observed in areas with high electric field strength. The logarithmic
regression of
the mean bird density vs. field strength groups (considering field
strength in 0.1V/m
increments) was R = -087 [1]P
= 00001
.
The results of this article
support the hypothesis that electromagnetic signals
are associated with the observed
decline in the sparrow population. We conclude
that electromagnetic pollution may be responsible, either by itself or
in combination
with other factors, for the observed decline of the species in European
cities during
recent years. The appearently strong dependence between bird density
and field
strength according to this work could be used for a more controlled
study to test
the hypothesis.
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