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distance between the phone's antenna—the
primary source of the RF—and the person's head.
The exposure to RF from mobile phones in which
the antenna is located at greater distances from the
user (on the outside of a car, for example) is
drastically lower than that from hand-held phones,
because a person's RF exposure decreases rapidly
with distance from the source. The safety of so-
called “cordless phones,” which have a base unit
connected to the telephone wiring in a house and
which operate at far lower power levels and
frequencies, has not been questioned.
How much evidence is there that hand-held mobile phones might be harmful?Briefly, there is not enough evidence to know for
sure, either way; however, research efforts are on-
going. The existing scientific evidence is conflicting
and many of the studies that have been done to
date have suffered from flaws in their research
methods. Animal experiments investigating the
effects of RF exposures characteristic of mobile
phones have yielded conflicting results. A few
animal studies, however, have suggested that low
levels of RF could accelerate the development of
cancer in laboratory animals. In one study, mice
genetically altered to be predisposed to developing
one type of cancer developed more than twice as
many such cancers when they were exposed to RF
energy compared to controls. There is much
uncertainty among scientists about whether results
obtained from animal studies apply to the use of
mobile phones. First, it is uncertain how to apply the
results obtained in rats and mice to humans.
Second, many of the studies that showed increased
tumor development used animals that had already
been treated with cancer-causing chemicals, and
other studies exposed the animals to the RF
virtually continuously—up to 22 hours per day.
For the past five years in the United States, the
mobile phone industry has supported research into
the safety of mobile phones. This research has