167
166
OTHER FUNCTIONS
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 kinds of phones are the subject of this update?
The term wireless phone refers here to hand-held 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 Federal Communications Commission
safety guidelines that were developed with the advice of 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 well within the FCC s compliance limits.
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
average period of phone use in these studies was around three years.
