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.
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