Siemens S40 - Manual (Page 45)

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How much evidence is there that
hand-held mobile phones might
be harmful?
Briefly, there is not enough evi-
dence to know for sure, either way;
however, research efforts are on-
going. The existing scientific evi-
dence is conflicting and many of
the studies that have been done to
date have suffered from flaws in
their research methods.
Animal experiments investigating
the effects of RF exposures charac-
teristic of mobile phones have
yielded conflicting results. A few
animal studies, however, have sug-
gested that low levels of RF could
accelerate the development of can-
cer in laboratory animals.
In one study, mice genetically
altered to be predisposed to devel-
oping one type of cancer devel-
oped more than twice as many
such cancers when they were
exposed to RF energy compared to
controls. There is much uncertainty
among scientists about whether
results obtained from animal stud-
ies apply to the use of mobile
phones.
First, it is uncertain how to apply
the results obtained in rats and
mice to humans.
Second, many of the studies
showed increased tumor develop-
ment used animals that had already
been treated with cancer-causing
chemicals, and other studies
exposed the animals to the RF vir-
tually continuously – up to 22 hours
per day.
For the past five years in the
United States, the mobile phone
industry has supported research
into the safety of mobile phones.
This research has resulted in two
findings in particular that merit
additional study:
• In a hospital-based, case-control
study, researchers looked for an
association between mobile phone
use and either glioma (a type of
brain cancer) or acoustic neuroma
(a benign tumor of the nerve
sheath). No statistically significant
association was found between
mobile phone use and acoustic
neuroma.
There was also no association
between mobile phone use and
gliomas when all types of gliomas
were considered together. It
should be noted that the aberage
length of mobile phone exposure in
this study was less than three
years.
When 20 types of glioma were
considered separately, however, an
association was found between
mobile phone use and one rare
type of glioma, neuroepithellioma-
tous tumors. It is possible with
multiple comparisons of the same
sample that this association
occurred by chance.
Moreover, the risk did not
increase with how often the mobile
phone was used, or the length of
the calls. In fact, the risk actually
decreased with cumulative hours
of mobile phone use.
FDA Update on mobile phone safety
The U.S. Food and Drug
Administration’s Center for
Devices and Radiological Health
Consumer Update on Mobile
Phones
FDA has been receiving inquiries
about the safety of mobile phones,
including cellular phones and PCS
phones. The following summarizes
what is know – and what remains
unknown – about whether these
products can pose a hazard to
health, and what can be done to
minimize any potential risk. This
information may be used to
respond to questions.
Why the concern?
Mobile phones emit low levels of
radiofrequency energy (i.e.,
radiofrequency radiation) in the
microwave range while being used.
They also emit very low levels of
radiofrequency energy (RF), consid-
ered non-significant, when in the
stand-by mode. It is well known
that high levels of RF can produce
biological damage through heating
effects (this is how your microwave
oven is able to cook food).
However, it is not known whether,
to what extent, or through what
mechanism, lower levels of RF
might cause adverse health effects
as well.
Although some research has
been done to address these ques-
tions, no clear picture of the biolog-
ical effects of this type of radiation
has emerged to date. Thus, the
available science does not allow us
to conclude that mobile phones are
absolutely safe, or that they are
unsafe.
However, the available scientific
evidence does not demonstrate
adverse health effects associated
with the use of mobile phones.
What kinds of phones are in
question?
Questions have been raised about
hand-held mobile phones, the kind
that have a built-in antenna that is
positioned close to the user’s
head during normal telephone con-
versation. These types of mobile
phones are of concern because of
the short distance between the
phone’s antenna – the primary
source of the RF – and the per-
son’s head.
The exposure to RF from mobile
phones in which the antenna is
located at greater distances from
the user (on the outside of a car,
for example) is drastically lower
than that from hand-held phones,
because a person’s RF exposure
decreases rapaidly with distance
from the source.
The safety of so-called “cordless
phones,” which have a base unit
connected to the telephone wiring
in a house and which oeprate at far
lower power levels and frequen-
cies, has not been questioned.
User guide S40 US 11/01/01 9:30 Side 86