User's Manual

Health and safety information
70
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 the 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 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.
What is FDA doing to find out more
about the possible health effects of
wireless phone RF?
E840-2.fm Page 48 Monday, May 14, 2007 9:04 AM