User's Manual

as t o be pre-disposed t o develop cancer in absence of RF exposure. Other
studies exposed t he anim als to RF for up to 22 hours per day. These
condit ions are not sim ilar t o t he condit ions under which people use
wireless phones, so we don't know with certainty what the results of such
studies m ean for hum an health.
Three large epidem iology studies have been published since Decem ber
2000. Between t hem , t he studies invest igat ed any possible association
between t he use of wireless phones and prim ary brain cancer, gliom a,
m eningiom a, or acoust ic neurom a, tum ors of t he brain or salivary gland,
leukem ia, or other cancers. None of t he studies dem onst rat ed the
exist ence of any harm ful health effect s from wireless phones RF
exposures. However, none of t he st udies can answer quest ions about
long- term exposures, since t he average period of phone use in these
studies was around t hree years.
W hat r esear ch is nee ded t o decide w he ther RF exposure fr om
w irele ss phones pose s a hea lth risk?
A com bination of laboratory st udies and epidem iological st udies of people
act ually using wireless phones would provide som e of the data t hat are
needed. Lifet im e anim al exposure st udies could be com pleted in a few
years. However, very large num bers of anim als would be needed t o
provide reliable proof of a cancer prom oting effect if one exists.
Epidem iological st udies can provide dat a that is direct ly applicable to
hum an populations, but ten or m ore years' follow- up m ay be needed to
provide answers about som e healt h effect s, such as cancer. This is
because the int erval between t he tim e of exposure to a cancer-causing
agent and t he t im e tum ors develop - if they do - m ay be m any, m any
years. The int erpretation of epidem iological st udies is ham pered by
difficult ies in m easuring act ual RF exposure during day- to- day use of
wireless phones. Many fact ors affect t his m easurem ent , such as the angle
at which t he phone is held, or which m odel of phone is used.
W hat is FDA doing t o find out m ore about the possible health
effects of w ireless phone RF?
FDA is working with t he U.S. National Toxicology Program and with
groups of invest igators around the world t o ensure that high priority
anim al st udies are conduct ed t o address im port ant questions about the
effect s of exposure to radio frequency energy (RF).
FDA has been a leading participant in the World Healt h Organization
int ernat ional Elect rom agnetic Fields ( EMF) Project since its inception in
1996. An influential result of this work has been t he developm ent of a
detailed agenda of research needs that has driven t he est ablishm ent of
new research program s around t he world. The Proj ect has also helped
develop a series of public inform ation docum ents on EMF issues.
FDA and Cellular Telecom m unications & I nternet Association (CTI A) have
a form al Cooperative Research and Developm ent Agreem ent (CRADA) t o
do research on wireless phone safety. FDA provides the scient ific