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Should harmful interference be found to occur, FDA
will conduct testing to assess the interference and
work to resolve the problem.
9. What are the results of the research done already?
The research done thus far has produced conflicting
results, and many studies have suffered from flaws in
their research methods. Animal experiments
investigating the effects of radio frequency energy
(RF) exposures characteristic of wireless phones have
yielded conflicting results that often cannot be
repeated in other laboratories. A few animal studies,
however, have suggested that low levels of RF could
accelerate the development of cancer in laboratory
animals. However, many of the studies that showed
increased tumor development used animals that had
been genetically engineered or treated with cancer
causing chemicals so as to be pre-disposed to develop
cancer in the absence of RF exposure. Other studies
exposed the animals to RF for up to 22 hours per day.
These conditions are not similar to the conditions
under which people use wireless phones, so we don’t
know with certainty what the results of such studies
mean for human health.
Three large epidemiology studies have been published
since December 2000. Between them, the studies
investigated any possible association between the use
of wireless phones and primary brain cancer, gioma,
meningioma, or acoustic neuroma, tumors of the
brain or salivary gland, leukemia, or other cancers.
None of the studies demonstrated the existence of
any harmful health effects from wireless phone RF
exposures. However, none of the studies can answer
questions about long-term exposures, since the
average period of phone use in these studies was
around three years.
10.What research is needed to decide whether RF
exposure from wireless phones poses a health
risk?
A combination of laboratory studies and
epidemiological studies of people actually using
wireless phones would provide some of the data that
are needed. Lifetime animal exposure studies could be
completed in a few years. However, very large
numbers of animals would be needed to provide
reliable proof of a cancer promoting effect if one
exists. Epidemiological studies can provide data that
is directly applicable to human populations, but 10 or
more years follow-up may be needed to provide
answers about some health effects, such as cancer.
This is because the interval between the time of