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Agosto 2005
Another
heat shock response study
Miyakoshi
and colleagues have added to the growing list of publications on
the effect of RF radiation on heat
shock proteins. They found that exposure to 1.95 GHz frequency
for up to 2 hours at SARs of 1, 2, and 10 W/kg did not affect the
growth of human glioma
cells, or the production of Hsp27 and Hsp70. They did find reduced
phosphorylation of Hsp27 at 10 W/kg, but not at 1 or 2 W/kg.
For
more, see "Research - Toxicological
Experiments - Others - Heat shock response".
Reference:
Miyakoshi J, Takemasa K, Takashima Y, Ding G-R, et al. Effects of
exposure to 1950 MHz radio frequency field on expression of Hsp70
and Hsp27 in human glioma cells. Bioelectromagnetics 2005;26:251-257.
Review of acoustic neuroma
The
March edition of "Radio Science Bulletin" contains a review
by James Lin on acoustic
neuroma. He discusses in detail the paper by Lonn and colleagues,
which was part of the INTERPHONE study, and briefly reviews other
publications on the subject.
For
more on this topic, see "Research
- Epidemiology".
Reference:
Lin JC (2005). Mobile phone use and benign tumors of the auditory
nerve. Radio Science Bulletin No 312 (March, 2005).
www.ursi.org
Genotoxicity
and RFR exposure
The
issue of whether or not radiofrequency radiation (RFR) at cell phone
frequencies can produce DNA breakage in exposed tissues has been
debated since the mid-1990s. Lai and Singh (1995, 1996) reported
that rats exposed for 2 hours to RFR at 2450 MHz and SARs of 0.6
and 1.2 W/kg, had increased DNA breaks in their brain cells. Others
have failed to reproduce these findings. Diem and colleagues have
now reported DNA breakage in human cells and rat tumour cells after
16 hours exposure to 1800 MHz at SAR of 2 W/kg. They found more
effect with intermittent exposure than continuous, and argue that
this supports the conclusion that the observed effects are non-thermal.
For
more, see Research - Toxicological
experiments - Cancer".
Reference:
Diem E, Schwarz C, Adlkofer F, Jahn O, et al. Non-thermal DNA breakage
by mobile-phone radiation (1800 MHz) in human fibroblasts and in
transformed GFSH-R17 rat granulosa cells in vitro. Mutat Res 2005;583:178-183.
Another
genotoxicity study shows no RFR effect
As
mentioned above, there have been a number of studies assessing whether
radiofrequency radiation (RFR) has a genotoxic
effect on cells. Most have failed to find an effect. Another study
has produced similar results. An Italian group that has been involved
in genotoxic research for many years exposed cells to 900 MHz RFR
for 2 hours. There was no evidence of DNA
damage or alteration of cell proliferation.
For
more, see "Research - Toxicological
experiments - Cancer".
Reference:
Zeni O, Romano M, Perotta A, Lioi MB, et al. Evaluation of genotoxic
effects in human peripheral blood leukocytes following an acute
in vitro exposure to 900 MHz radiofrequency fields. Bioelectromagnetics
2005;26:258-265.
Cell
phone RFR and allergy tests
A recent report suggests that exposure to RFR from a cell phone
for 30 minutes can lead to changes in allergy blood tests in patients
with atopic eczema dermatitis syndrome. The report does not offer
any explanation for a mechanism that might produce this effect.
For
more, see "Research - Clinical
Experiments - Others - Immune system".
Reference: Kimata H. Microwave radiation from
cellular phones increases allergen-specific IgE production. Allergy
2005;60:838-9
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