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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.
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 the FDA doing to find out more about the possible
health effects of wireless phone RF?
The 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).
The 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.
Safety Guidelines
