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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.
5) What research is needed to decide whether RF exposure from wireless phones
poses a health risk?
A combination of laboratory studies and epidemiological studies of people
actually using wireless phones would provide some of the data that are needed.
Lifetime animal exposure studies could be completed in a few years. However,
very large numbers of animals would be needed to provide reliable proof of a
cancer promoting effect if one exists. Epidemiological studies can provide data
that is directly applicable to human populations,
but 10 or more years’ follow-up may be needed to provide answers about some
health effects, such as cancer. This is because the interval between the time of
exposure to a cancer-causing agent and the time tumors develop - if they do-may
be many, many years. The interpretation of epidemiological studies is hampered
by difficulties in measuring actual RF exposure during day-to-day use of wireless
phones. Many factors affect this measurement, such as the angle at which the
phone is held, or which model of phone is used.
6) What is FDA doing to find out more about the possible health effects of wireless
phone RF?
FDA is working with the U.S. National Toxicology Program and with groups of
investigators around the world to ensure that high priority animal studies are
conducted to address important questions about the effects of exposure to
radiofrequency energy (RF). FDA has been a leading participant in the World
Health Organization International Electromagnetic Fields (EMF) Project since its
inception in 1996. An influential result of this work has been the development of
a detailed agenda of research needs that has driven the establishment of new
research programs around the world. The Project has also helped develop a series
of public information documents on EMF issues. FDA and the Cellular
Telecommunications & Internet Association (CTIA) have a formal Cooperative
Research and Development Agreement (CRADA) to do research on wireless
phone safety. FDA provides the scientific oversight, obtaining input from experts
in government, industry, and academic organizations. CTIA-funded research is
conducted through contracts to independent investigators. The initial research will
include both laboratory studies and studies of wireless phone users. The CRADA
