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 todecide whether RF exposure fromwireless phones poses a healthrisk?
Acombination of laboratory
studiesand epidemiological studies
of people actually using wireless
phones would provide some of the
datathatareneeded. 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 findout more about the possiblehealth effects of wireless phoneRF?
The FDAis working with the U.S.
National Toxicology Program and
with groups of investigators around
the world toensurethathigh
priority animal studies are
conducted to address important
questions about the effects of
exposure to Radio Frequency (RF)
energy.
The FDA has been a leading
participant in the World Health
Organization International Electro
Magnetic Fields (EMF) Project
since itsinception in 1996. An
influential result of this work has
been the development of a
detailed agenda of research needs
thathasdriven the establishment
of newresearch programs around
the world. The project has also
helped develop a series of public
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