Hitachi SH-P300, Online User'S Manual

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Section 4: Safety Guidelines and Warranty Information
204 4A: Safety
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.
20. 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.