phone effects on EEG in narcolepsy
There have been
a number of reports of EEG studies in subjects exposed to RF radiation
(see "Research - Clinical"
for details). A recent study reports experiments on subjects with
narcolepsy, who fall asleep suddenly in certain situations, mainly
during monotonous activities.
were exposed for 45 minutes to 900 MHz, SAR 0.06 W/kg, close to
their right ear. No changes were seen on the EEG after this exposure.
The authors had postulated that the RF field would produce a hypnotic
effect in these patients, but this was not seen.
A subgroup was
studied while performing a visual task. Some EEG changes were seen
in response to certain visual stimuli. These were mainly seen in
the right hemisphere. The reaction time was also shortened by 20
ms in response to target stimuli. The authors suggest that the RF
radiation might enhance performance in subjects with narcolepsy.
Jech R, Sonka K, Ruzicka E, Nebuzelsky, et al. Electromagnetic field
of mobile phone affects visual event related potential in patients
with narcolepsy. Bioelectromagnetics 2001;22:519-528.
more negative genotoxicity studies
New" of March of this year we reported a study by Vijayalaxmi
and colleagues that failed to find evidence of genotoxicity in blood
cells exposed to 835.62 MHz continuous wave radiation (FDMA). SThese
same authors have now reported similar negative results when lymphocytes
were exposed for 24 hours to continuous -wave 847.74 MHz RF radiation
(CDMA) at a SAR of 4.9 or 5.5 W/kg.
In another study
this group report a study in which rats were exposed to 2450 MHz
continuous wave radiation for 24 hours. The average whole-body SAR
was 12W/kg. There was no difference in the incidence of micronuclei
(a sign of chromosome damage) in red blood or bone marrow cells
in the exposed rats, compared to controls.
of genotoxic studies can be found in "Toxicological
Experiments - cancer studies".
Vijayalaxmi, Bisht KS, Pickard WF, Meltz ML, Roti Roti JL, et al.(2001):
Chromosome damage and micronucleus formation in human blood lymphocytes
exposed in vitro to radiofrequency radiation at a cellular telephone
frequency (847.74 MHz, CDMA). Radiation Research 156:430-433.
Pickard WF, Bisht KS, Prihoda TJ, et al. (2001): Micronuclei in
the peripheral blood and bone marrow cells of rats exposed to 2450
MHz radiofrequency radiation. International Journal of Radiation
Effects of low intensity RF fields in rat brain
This study explored
the effect of 700 MHz continuous wave RF fields at low intensity
on the electrical activity in slices of rat brain from the hippocampus
area. The maximum field intensity was calculated to produce a SAR
between 0.0016 and 0.0044 W/kg. Changes were noted in the electrical
activity of the rat brain slices. These results were seen in the
absence of detectable temperature change. The authors state that
the hippocampus is important in spatial learning and memory processes,
and that the changes in electrical excitability may be consistent
with reported behavioural effects of RF fields.
Tattersall JEH, Scott IR, Wood SJ, Nettell JJ, et al. (2001): Effects
of low intensity radiofrequency electromagnetic fields on electrical
activity in rat hippocampal slices. Brain Research 904:43-53.