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4. 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 (RF) energy 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 do not 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,
glioma, 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.
5. 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 ten 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
exposure to a cancer-causing agent and the
time tumors develop — if they do — may
