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wireless phones, so we don't 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 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.