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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 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 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 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.