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What kinds of phones are in question?
Questions have been raised about hand-held mobile phones, the
kind that have a built-in antenna that is positioned close to the
user's head during normal telephone conversation. These types
of mobile phones are of concern because of the short 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.
User.Guide.Tarpon.book Page 94 Thursday, April 26, 2001 2:23 PM