Health and Safety Information 136
Consumer Information on Wireless Phones
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 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 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
phones 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 ten 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.
t729.book Page 136 Thursday, July 5, 2007 3:47 PM
