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Safety
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 be many, many years. The
interpretation of epidemiological
studies is hampered by difficulties
in measuring actual RF exposure
during day-to-day use of wireless
phones. Many factors affect this
measurement, such as the angle at
which the phone is held, or which
model of phone is used.
6. What is the FDA doing to find
out more about the possible
health effects of wireless phone
RF?
The FDA is working with the U.S.
National Toxicology Program and