User's Manual

far lower power levels and frequencies, has not been ques -
tioned.
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 develop -
ment of cancer in laboratory animals. In one study, mice geneti -
cally 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 resulted in two findings in particular
that merit additional study:
In a hospital - based, case - control study, researchers looked
for
an association between mobile phone use and either
glioma
(a type of brain cancer) or acoustic neuroma (a
benign tumor of the nerve sheath). No statistically significant
association was found between mobile phone use and acous
-
tic neuroma. There was also no association between mobile
phone use and gliomas when
all types of types of gliomas
were considered together.
It should be noted that the aver -
age length of mobile phone exposure in this study was less
than three years.