Samsung SCH-R100 User Manual page 86

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.
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