Evidence for Effects on Neurology and Behavior - BioInitiative Report

I. Introduction
This chapter is a brief review of recent studies on the effects of radiofrequency radiation (RFR)
on neuronal functions and their implication on learning and memory in animal studies, effects on
electrical activity of the brain and relation to cognitive functions, and finally a section on the
effects of cell phone radiation on the auditory system. There is also a set of studies reporting
subjective experience in humans exposed to RFR. This includes reports of fatigue, headache,
dizziness, and sleep disturbance, etc.
The close proximity of a cellular telephone antenna to the user’s head leads to the deposition of a
relatively large amount of radiofrequency energy in the head. The relatively fixed position of the
antenna to the head causes a repeated irradiation of a more or less fixed amount of body tissue,
including the brain at a relatively high intensity to ambient levels. The question is whether such
exposure affects neural functions and behavior.
II. Chemical and cellular changes
Several studies have investigated the effect of RFR on the cholinergic system because of its
involvement in learning and wakefulness and animals. Testylier et al. [2002] reported
modification of the hippocampal cholinergic system in rats during and after exposure to lowintensity
RFR. Bartier et al. [2005] reported that RFR exposure induced structural and
biochemical changes in AchE, the enzyme involved in acetylcholine metabolism. Vorobyov et al.
[2004] reported that repeated exposure to low-level extremely low frequency-modulated RFR
affected baseline and scopolamine-modified EEG in freely moving rats. However, recently
Crouzier et al [2007] found no significant change in acetylcholine-induced EEG effect in rats
exposed <strong>for</strong> 24 hours to a 1.8 MHz GSM signal at 1.2 and 9 W/cm 2 .
There are several studies on the inhibitory and excitatory neurotransmitters. A decrease in
GABA, an inhibitory transmitter, content in the cerebellum was reported by Mausset et al.
[2001] after exposure to RFR at 4 W/kg. The same researchers [Maussset-Bonnefont et al., 2004]
also reported changes in affinity and concentration of NMDA and GABA receptors in the rat
brain after an acute exposure at 6 W/kg. Changes in GABA receptors has also been reported by
Wang et al. [2005], and reduced excitatory synaptic activity and number of excitatory synapses
in cultured rat hippocampal neurons have been reported by Xu et al. [2006] after RFR exposure.
Related to the findings of changes in GABA in the brain is that RFR has been shown to facilitate
seizure in rats given subconvulsive doses of picotoxin, a drug that blocks the GABA system
[Lopez Martin et al., 2006]. This finding raises the concern that humans with epileptic disorder
could be more susceptible to RFR exposure.
Not much has been done on single cell in the brain after RFR exposure. Beason and Semm
[2002] reported changes in the amount of neuronal activity by brain cells of birds exposed to
GSM signal. Both increase and decrease in firing were observed. Sal<strong>for</strong>d et al. [2003] reported
cellular damage and death in the brain of rat after acute exposure to GSM signals. Tsurita et al.
[2000] reported no significant morphological change in the cerebellum of rats exposed <strong>for</strong> 2-4
weeks to 1439-MHz TDMA field at 0.25 W/kg. More recently, Joubert et al. [2006, 2007] found
no apoptosis in rat cortical neurons exposed to GSM signals in vitro.
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