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FDA CONSUMER UPDATE
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These types of wireless phones can expose the user to measurable radiofrequency
energy (RF) because of the short distance between the phone and the user’s head.
These RF exposures are limited by Federal Communications Commission safety
guidelines that were developed with the advice of FDA and other federal health and
safety agencies. When the phone is located at greater distances from the user, the
exposure to RF is drastically lower because a person’s RF exposure decreases
rapidly with increasing distance from the source. The so-called “cordless phones,”
which have a base unit connected to the telephone wiring in a house, typically
operate at far lower power levels, and thus produce RF exposures far below the
FCC safety limits.
4. 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 predisposed 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 neu-
roma, 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.
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.
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