study fails to confirm phone effect on brain function
There have been
several studies that have suggested that exposure to RF radiation
from cell phones may enhance cognitive
function. The authors of one of these studies have attempted to
replicate it (Koivisto et al., 2000a), but with improved methodology.
They included double blind testing, larger sample size, multicentre
testing, and additional tests. In the present study they found that
the electromagnetic field had no effect on cognitive functioning.
For more, see "Research
- Clinical Experiments- cognitive function".
Haarala C, Bjornberg L, Ek M, Laine M, et al. (2003): Effect of
902 MHz electromagnetic field emitted by mobile phones on human
cognitive function: A replication study. Bioelectromagnetics 24:283-288.
RF radiation from cell phones only affects rats'
behaviour when temperature is increased
has suggested that RF radiation from cell phones can disrupt animal
behaviour and cognitive function. Other research, however, has shown
no effect. In a recent study, in which rats learned how to find
food in a maze, there was no effect on the animals' performance
unless they were exposed at high SAR levels, sufficient to elevate
body temperature. For more, see "Research
- Toxicological Experiments - brain function".
Yamaguchi H, Tsurita G, Ueno S, Watanabe S, et al (2003): 1439 MHz
pulsed TDMA fields affect performance of rats in a T-maze task only
when body temperature is elevated. Bioelectromagnetics 24:223-230.
No effect on melatonin secretion from cell phones
Melatonin is a hormone
secreted by the pineal gland in the brain. Its secretion is usually
estimated by measurement of 6-hydroxymelatonin sulfate (6-OHMS)
excretion in the urine. Another study has failed to show any effect
on 6-OHMS excretion from exposure to an electromagnetic field (EMF)
emitted by a cellular phone. Subjects were exposed from 7 p.m to
8 p.m. to an EMF from a cell phone at 900 MHz, pulsed with 217 Hz,
SAR 1.23 W/kg. Their urine was collected from 7 p.m to 7a.m. Mean
6-OHMS levels did not differ significantly between the exposed and
non-exposed experiment, and individuals did not show any difference
in their excretion patterns. For more, see "Research
- Clinical Experiments - hormone secretion".
Bortkiewicz A, Pilacik B, Gadzicka E, Szymczak W (2002): The excretion
of 6-hydroxymelatonin sulfate in healthy young men exposed to electromagnetic
fields emitted by cellular phone - an experimental study. Neuroendocrinology
Letters 23 (suppl 1):88-91.
research program announces additional studies
The Mobile Telecommunications
and Health Research (MTHR) Programme in the UK has announced that
it will fund additional projects. One will investigate the risk
of early childhood cancers, in particular leukaemia and non-Hodgkin's
lymphoma, among the population residing near mobile phone base stations.
A case-control approach
will be used.
will examine whether mobile phone signals cause symptoms such as
headaches, nausea, dizziness and fatigue. It will also investigate
whether the signals affect the levels of certain hormones
that are important in regulating metabolism.
"Hypersensitive" people who often experience symptoms
when using a mobile phone will be compared to a group who do not
experience any symptoms.
of the Programme can be found at "Research
Programs " and at www.mthr.org.uk.