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44..WWhhaatt aarree tthhee rreessuullttss ooff tthhee rreesseeaarrcchh ddoonnee aallrreeaaddyy??
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 Radio
Frequency 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.
55..WWhhaatt rreesseeaarrcchh iiss nneeeeddeedd ttoo ddeecciiddee wwhheetthheer
r RRFF eexxppoossuurree
ffrroomm wwiirreelleessss pphhoonneess ppoosseess aa hheeaalltthh rriisskk??
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.
66..WWhhaatt iiss tthhee FFDDAA ddooiinngg ttoo ffiinndd oouutt mmoorree aab
boouutt tthhee ppoossssiibbllee
hheeaalltthh eeffffeeccttss ooff wwiirreelleessss pphhoonnee RRFF??
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 Radio
Frequency 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
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