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Appendix
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4. What are the results of the research done
already?
The research done thus far has produced conflict-
ing results, and many studies have suffered from
flaws in their research methods. Animal experi-
ments 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 develop-
ment of cancer in laboratory animals. However,
many of the studies that showed increased tumor
development used animals that had been geneti-
cally engineered or treated with cancer-causing
chemicals so as to be predisposed to develop can-
cer 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 condi-
tions 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 investi-
gated 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 epide-
miological 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 epidemio-
logical studies is hampered by difficulties in mea-
suring actual RF exposure during day-to-day use
of wire-less phones. Many factors affect this mea-
surement, such as the angle at which the phone is
held, or which model of phone is used.
6. What is FDA doing to find out more about the
possible health effects of wireless phone RF?
FDA is working with the U.S. National Toxicology
Program and with groups of investigators around
the world to ensure that high priority animal stud-
ies are conducted to address important questions
about the effects of exposure to radiofrequency
energy (RF). FDA has been a leading participant
in the World Health Organization International
Electromagnetic Fields (EMF) Project since its incep-
tion in 1996. An influential result of this work has
been the development of a detailed agenda of
research needs that has driven the establishment
of new research programs around the world.
The Project has also helped develop a series of
public information documents on EMF issues. FDA
and the Cellular Telecommunications & Internet
Association (CTIA) have a formal Cooperative
Research and Development Agreement (CRADA)
to do research on wireless phone safety. FDA pro-
vides the scientific oversight, obtaining input from
experts in government, industry, and academic
organizations. CTIA-funded research is conducted
through contracts to independent investigators.
The initial research will include both labora-tory
studies and studies of wireless phone users. The
CRADA will also include a broad assessment of
additional research needs in the context of the lat-
est research developments around the world.
7. How can I find out how much radiofrequency
energy exposure I can get by using my wireless
phone?
All phones sold in the United States must comply
with Federal Communications Commission (FCC)
guidelines that limit radiofrequency energy (RF)
exposures. FCC established these guidelines in con-
sultation with FDA and the other federal health
and safety agencies. The FCC limit for RF expo-
sure from wireless telephones is set at a Specific
Absorption Rate (SAR) of 1.6 watts per kilogram
(1.6 W/kg). The FCC limit is consistent with the
safety standards developed by the Institute of
Electrical and Electronic Engineering (IEEE) and
the National Council on Radiation Protection and
Measurement. The exposure limit takes into con-
sideration the body’s ability to remove heat from
the tissues that absorb energy from the wireless
phone and is set well below levels known to have
effects. Manufacturers of wireless phones must
report the RF exposure level for each model of
phone to the FCC. The FCC website (http://www.
fcc.gov/oet/rfsafety) gives directions for locating
the FCC identification number on your phone so
you can find your phone’s RF exposure level in the
online listing.
8. What has FDA done to measure the radiofre-
quency energy coming from wireless phones?
The Institute of Electrical and Electronic Engineers
(IEEE) is developing a technical standard for mea-
suring the radiofrequency energy (RF) exposure
from wireless phones and other wireless handsets
with the participation and leadership of FDA scien-
tists and engineers. The standard, “Recommended
Practice for Determining the Spatial-Peak Specific
Absorption Rate (SAR) in the Human Body Due to
Wireless Communications Devices: Experimental
Techniques,” sets forth the first consistent test
methodology for measuring the rate at which RF
is deposited in the heads of wireless phone users.
The test method uses a tissue-simulating model of
the human head. Standardized SAR test methodol-
ogy is expected to greatly improve the consistency
of measurements made at different laboratories