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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 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 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.
