Safety Guidelines
108
Base stations are thus not the subject
of the safety questions discussed in this
document.
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
radio frequency(RF) energy 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 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 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