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Safety
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.
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.
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).
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