Safety Guidelines
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 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 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,
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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 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