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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 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, 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
phones 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.
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
