User's Manual

Chapter 7 Safety and Warranty 109
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.
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