RF exposure and melatonin production
of previous studies on melatonin
production after RF exposure have been inconsistent. Most have shown
no effect. Wood and colleagues exposed 55 volunteers to 895 MHz
RFR for 30 minutes. Output of a melatonin metabolite was the same
in exposed compared with control subjects in one measure. By another
method of measurement the pre-bedtime output of melatonin was decreased
in the RFR-exposed subjects. This was entirely due to 4 individuals
who had outputs that were extreme "outliers" compared
to the others. It was thought that this was due to this small group
having delayed onset of melatonin production, or some confounding
factor e.g. prior exposure to bright light before coming to the
more, see "Research - Clinical
- Hormone secretion".
Wood AW, Loughran SP, Stough C. Does evening exposure to mobile
phone radiation affect subsequent melatonin production? Int J Radiat
phone related symptoms - no difference in controlled tests
people complain of electrical hypersensitivity (EHS) - see "What's
New, June '02, April '03, September
'05, and April '06". However,
when people with EHS have been tested in controlled trials, they
have been unable to detect the RF-exposure condition, as opposed
to a sham-exposure. Wilen and colleagues carried out a number of
physiological measurements and cognitive tests on subjects who complained
of symptoms related to mobile phones, but who did not complain of
EHS. There were no significant differences related to RF exposure
between cases and controls. There was increased heart rate variability
in the cases during a critical flicker fusion threshold test and
a memory test.
The authors considered that this might be due to differences in
the autonomic nervous system regulation between persons with MP
related subjective symptoms and persons with no such symptoms.
For more, see "Research -
Clinical - Others- General Health effects, including electromagnetic
field hypersensitivity", and FAQ
Wilen J, Johansson A, Kalezic N, Lyskov E, et al. Psychological
tests and provocation of subjects with mobile phone related symptoms.
on effect of RF exposure on function of the immune system
have been few studies of the effect of RF exposure on immune function.
Tuschl and colleagues tested the effect of short-term exposure from
a GSM Basic signal on human lymphocytes
and monocytes. They found no evidence that the RF exposure had any
effect on the numerous tests of immune function that they performed.
more, see “Research –
Toxicological – Others -Immune system”.
Tuschl H, Novak W, Molla-Djafari H. In vitro effects of GSM modulated
radiofrequency fields on human immune cells. Bioelectromagnetics
No effect of RFR on cell death
and colleagues did experiments on a neuroblastoma cell line. This
is a solid tumour, mainly found in children. They exposed the cells
to RFR from a 900 MHz signal for up to 72 hours. They found no alterations
in cell death, proliferation, or differentiation in the exposed
cells, when compared with sham-exposed cells.
more, see "Research - Toxicological
- Others - Cell death".
Merola P, Marino C, Lovisolo GA, Pinto R, et al. Proliferation and
apoptosis in a neuroblastoma cell line exposed to 900 MHz modulated
radiofrequency field. . Bioelectromagnetics 2006;27:164-171.
analyses from Hardell's group
Another publication has emerged from Hardell and colleagues in Sweden.
This one reported the combined results from two case-control studies
on the use of cell and cordless phones and the risk for malignant
tumour. The studies covered the period 1997-2003. They found increased
risks for analogue, digital, and cordless phones, particularly for
those who had cumulative use of >2,000 hours, and for those with
> 10 years use. Multivariate analyses reduced the risk assessments.
results from this group are consistently different from those of
others who have studied this problem. The reasons for this are debated
in epidemiological circles. For more, see "Research
Hardell L, Carlberg M, Mild KH. Pooled analyses of two case-control
studies on use of cellular and cordless telephones and the risk
for malignant brain tumours diagnosed in 1997-2003. Int Arch Occup
Environ Health 2006;published on-line March 16.