Owners manual

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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 do not 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.
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 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.
Safety