Cheap phone cards
When electric power was introduced in the 19th century, some Victorian
consumers worried about the risks of exposure to the force "fields"
associated with electricity; contemporary scientists could give them
no absolute reassurance.
The health effects of electromagnetic fields remain uncertain today,
after hundreds of scientific studies and reviews -- the latest by Sir
William Stewart's expert committee.
Power lines, household circuits, computer screens, mobile phones and
their base stations all give off EMF at varying frequencies. Although
laboratory experiments leave no doubt that these fields affect living
cells, large-scale studies of human beings have not produced consistent
evidence of harm to people from the EMF exposures experienced in real
As the World Health Organisation puts it: "Expert committees that have
reviewed this evidence have consistently found it to be too weak to be
persuasive ... But clearly there is considerable scientific uncertainty
as well as a high level of public apprehension about the issue."
Although most research into the effect on the brain of microwave
radiation from mobile phones has been reassuring, a few studies have
caused concern. For example, research sponsored by the US telecoms
industry found an association between one rare type of brain cancer
(neuro-epithelliomatous tumours) and mobile phone use.
A study in Sweden found that some brain tumours were more likely to
occur on the side of the head on which the mobile phone was usually
held. Bristol University researchers found that people made visual
choices more quickly when exposed to microwave radiation, possibly
because this stimulated electrical activity in the brain.
A popular expression has mobiles "cooking the brain." In fact,
measurements show that a phone held close to the head raises the brain
temperature by no more than a fraction of a degree - less than the
natural variation in temperature during the day.
With an estimated 300m mobile phone users worldwide, even a small
health risk could cause hundreds of extra brain tumours. Such a weak
link would not have been picked up by the studies undertaken so far,
but it may be detected by more extensive international research,
involving several thousand brain cancer patients, that will be carried
out under the auspices of the International Agency for Research in
Cancer over the next few years.
Meanwhile new technology is likely to reduce any risks by cutting
radiation exposure. An international standard called Bluetooth will
enable mobile handsets to communicate at extremely low power with a
more powerful network transmitter in the owner's handbag or briefcase.
Bluetooth technology will cut EMF exposure to the level of a "cordless
phone" with a base station at home.
But road safety campaigners point out that the main, proven danger of
mobile phones is not radiation but the fact that they increase the
risk of having an accident if they are used while driving. Even a
hands-free set can be dangerous if an animated conversation distracts