FDA has tested hearing aids for interference from handheld wireless phones and
helped develop a voluntary standard sponsored by the Institute of
Electrical and Electronic Engineers (IEEE). This standard specifies test methods and
performance requirements for hearing aids and wireless phones so that that no
interference occurs when a person uses a compatible phone and a compatible
hearing aid at the same time. This standard was approved by the IEEE in 2000.
FDA continues to monitor the use of wireless phones for possible interactions with
other medical devices. Should harmful interference be found to occur, FDA will
conduct testing to assess the interference and work to resolve the problem.
10. What are the results of the research done already?
The research done thus far has produced conflicting results, and many studies have
suffered from flaws in their research methods. Animal experiments investigating the
effects of radiofrequency energy (RF) exposures characteristic of wireless phones
have yielded conflicting results that often cannot be repeated in other laboratories.
A few animal studies, however, have suggested that low levels of RF could
accelerate the development of cancer in laboratory animals. However, many of the
studies that showed increased tumor development used animals that had been
genetically engineered or treated with cancer-causing chemicals so
as to be pre-disposed to develop cancer in the absence of RF exposure. Other
studies exposed the animals to RF for up to 22 hours per day. These conditions are not
similar to the conditions under which people use wireless phones, so we don t know
with certainty what the results of such studies mean for human health.
Three large epidemiology studies have been published since December 2000.
Between them, the studies investigated any possible association between the use of
wireless phones and primary 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.
11. 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
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