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 10 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 with groups of
investigators around the world to ensure that
high priority animal studies are conducted
to address important questions about the
effects of exposure to radiofrequency energy
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