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FDA shares regulatory responsibilities for wireless phones with
the Federal Communications Commission (FCC). All phones that
are sold in the United States must comply with FCC safety
guidelines that limit RF exposure. FCC relies on FDA and other
health agencies for safety questions about wireless phones.
FCC also regulates the base stations that the wireless phone
networks rely upon. While these base stations operate at higher
power than do the wireless phones themselves, the RF
exposures that people get from these base stations are typically
thousands of times lower than those they can get from wireless
phones.
Base stations are thus not the primary subject of the safety
questions discussed in this document.
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 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 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 phones 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.
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.