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
diffi culties 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.
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