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Safety Guidelines
3. What kinds of phones are the subject of this
update?
The term ‘wireless phone’ refers here to handheld
wireless phones with built-in antennas, often called
‘cell’, ‘mobile’, or ‘PCS’ phones. These types of
wireless phones can expose the user to measurable
radiofrequency energy (RF) because of the short
distance between the phone and the user’s head.
These RF exposures are limited by FCC safety
guidelines that were developed with the advice of
the FDA and other federal health and safety
agencies. When the phone is located at greater
distances from the user, the exposure to RF is
drastically lower because a person’s RF exposure
decreases rapidly with increasing distance from the
source. The so-called ‘cordless phones,’ which have
a base unit connected to the telephone wiring in a
house, typically operate at far lower power levels,
and thus produce RF exposures far below the FCC
safety limits.
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, 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
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