Between them, the studies investigated any
possible association between the use of wireless
phones and primary brain cancer, glioma,
meningioma, or acoustic neu-roma, 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 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 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
radiofrequency energy (RF) 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 predisposed
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 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.
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