
as to be pre-disposed t o develop cancer in absence of RF exposure. Ot her
studies exposed the anim als to RF for up t o 22 hours per day. These
conditions are not sim ilar t o t he condit ions under which people use
wireless phones, so we don't know wit h cert aint y what t he results of such
studies m ean for hum an health.
Three large epidem iology st udies have been published since Decem ber
2000. Bet ween them , the st udies 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, t um ors of the brain or salivary gland,
leukem ia, or other cancers. None of t he st udies dem onst rat ed t he
exist ence of any harm ful health effect s from wireless phones RF
exposures. However, none of the studies can answer quest ions about
long- t erm exposures, since t he average period of phone use in t hese
studies was around t hree years.
W ha t r esea r ch is ne e de d t o de cide w het he r RF exposure fr om
w irele ss phone s poses a healt h risk?
A com bination of laboratory studies and epidem iological st udies of people
actually using wireless phones would provide som e of the data t hat are
needed. Lifetim e anim al exposure st udies could be com plet ed in a few
years. However, very large num bers of anim als would be needed to
provide reliable proof of a cancer prom ot ing effect if one exist s.
Epidem iological st udies can provide dat a t hat is direct ly applicable to
hum an populat ions, but ten or m ore years' follow - up m ay be needed t o
provide answers about som e healt h effect s, such as cancer. This is
because t he int erval between t he t im e of exposure t o a cancer- causing
agent and the 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 exposur e dur ing day- t o- 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 or e a bou t t he possible he a lt h
effects of w ire le ss phone RF?
FDA is working with t he U.S. National Toxicology Program and with
groups of invest igators around t he world t o ensure that high priority
anim al st udies are conduct ed t o address im port ant questions about t he
effect s of exposure t o radio frequency energy ( RF) .
FDA has been a leading part icipant in t he World Health Organization
int er nat ional Elect rom agnet ic Fields ( EMF) Proj ect since it s incept ion in
1996. An influential result of this work has been t he developm ent of a
detailed agenda of research needs t hat has driven the establishm ent of
new research program s around t he wor ld. The Proj ect has also helped
develop a series of public inform ation docum ent s on EMF issues.
FDA and Cellular Telecom m unications & I nt ernet Associat ion (CTI A) have
a form al Cooperative Research and Dev elopm ent Agreem ent ( CRADA) t o
do research on wireless phone safet y. FDA provides the scient ific