user, the exposure to RF is
drastically lower because a person's
RF exposure decreases rapidly with
increasing distance from the source.
The so-called "cordless phones, "
which have a base unit connected to
the telephone wiring in a house,
typically operate at far lower power
levels, and thus produce RF
exposures far below the FCC safety
limits.
4. What are the results of the
research done already?
The research done thus far has
produced conflicting results, and
many studies have suffered from
flaws in their research methods.
Animal experiments investigating the
effects of Radio Frequency (RF)
energy exposures characteristic of
wireless phones have yielded
conflicting results that often cannot
be repeated in other laboratories. A
few animal studies, however, have
suggested that low levels of RF
could accelerate the development of
cancer in laboratory animals.
However, many of the studies that
showed increased tumor
development used animals that had
been genetically engineered or
treated with cancer-causing
chemicals so as to be pre-disposed
to develop cancer in the absence of
RF exposure. Other studies exposed
the animals to RF for up to 22 hours
per day. These conditions are not
similar to the conditions under which
people use wireless phones, so we
do not 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 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 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
Safety
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