Publicidad
Idiomas disponibles
Idiomas disponibles
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.
122
AX5450
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 the FDA doing to find out more about
the possible health effects of wireless phone
RF?
The FDA is working with the U.S. National
Toxicology Program and with groups of
investigators around the world to ensure that high
AX5450
123
Publicidad
