in a house, typically operate at far lower power levels, and thus produce RF exposures far below the FCC
safety limits.
4. What are the results of the research done already?
The research done thus far has produced conflicting results, and many studies have suffered from flaws
in their research methods. Animal experiments investigating the effects of Radio Frequency (RF) energy
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
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 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.
6. What is the FDA doing to find out more about the possible health effects of wireless phone RF?
The FDA is working with the U.S. National Toxicology Program and with groups of investigators around the
world to ensure that high priority animal studies are conducted to address important questions about the
effects of exposure to Radio Frequency (RF) energy.
The FDA has been a leading participant in the World Health Organization International Electro Magnetic Fields
(EMF) Project since its inception 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.
The FDA and the Cellular Telecommunications & Internet Association (CTIA) have a formal Cooperative
Research And Development Agreement (CRADA) to do research on wireless phone safety. The FDA provides
the scientific oversight, obtaining input from experts in government, industry, and academic organizations.
CTIA-funded research is conducted through contracts with independent investigators. The initial research will
include both laboratory studies and studies of wireless phone users. The CRADA will also include a broad
assessment of additional research needs in the context of the latest research developments around the world.
7. How can I find out how much Radio Frequency 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 Radio Frequency (RF) energy exposures. The FCC established these guidelines in consultation with
the FDA and the other federal health and safety agencies. The FCC limit for RF exposure from wireless phones
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 consideration 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 the FDA done to measure the Radio Frequency energy coming from wireless phones?
The Institute of Electrical and Electronic Engineers (IEEE) is developing a technical standard for measuring
the Radio Frequency (RF) energy exposure from wireless phones and other wireless handsets with the
participation and leadership of FDA scientists 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 methodology is expected to greatly
improve the consistency of measurements made at different laboratories on the same phone. SAR is the
measurement of the amount of energy absorbed in tissue, either by the whole body or a small part of the
body. It is measured in watts/kg (or milliwatts/g) of matter. This measurement is used to determine whether
a wireless phone complies with safety guidelines.
9. What steps can I take to reduce my exposure to Radio Frequency energy from my wireless phone?
If there is a risk from these products — and at this point we do not know that there is — it is probably
very small. But if you are concerned about avoiding even potential risks, you can take a few simple steps to
minimize your exposure to Radio Frequency (RF) energy. Since time is a key factor in how much exposure
a person receives, reducing the amount of time spent using a wireless phone will reduce RF exposure. If
you must conduct extended conversations by wireless phone every day, you could place more distance
between your body and the source of the RF, since the exposure level drops off dramatically with distance.
For example, you could use a headset and carry the wireless phone away from your body or use a wireless
phone connected to a remote antenna. Again, the scientific data does not demonstrate that wireless phones
are harmful. But if you are concerned about the RF exposure from these products, you can use measures like
those described above to reduce your RF exposure from wireless phone use.
10. What about children using wireless phones?
The scientific evidence does not show a danger to users of wireless phones, including children and teenagers.
If you want to take steps to lower exposure to Radio Frequency (RF) energy, the measures described above
would apply to children and teenagers using wireless phones. Reducing the time of wireless phone use and
increasing the distance between the user and the RF source will reduce RF exposure.
Some groups sponsored by other national governments have advised that children be discouraged from using
wireless phones at all. For example, the government in the United Kingdom distributed leaflets containing
such a recommendation in December 2000. They noted that no evidence exists that using a wireless phone
causes brain tumors or other ill effects. Their recommendation to limit wireless phone use by children was
strictly precautionary; it was not based on scientific evidence that any health hazard exists.
11. What about wireless phone interference with medical equipment?
Radio Frequency (RF) energy from wireless phones can interact with some electronic devices. For this reason,
the FDA helped develop a detailed test method to measure Electro Magnetic Interference (EMI) of implanted
cardiac pacemakers and defibrillators from wireless telephones. This test method is now part of a standard
sponsored by the Association for the Advancement of Medical Instrumentation (AAMI). The final draft, a
