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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 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, glaucoma, 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 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
threat?
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 be
many, many years. The interpretation of epidemiological