4. Message from the FDA
The U.S. Food and Drug Administration (FDA) provides the following consumer
information about wireless phones.
See http://www.fda.gov/cellphones/ for updated information.
Do wireless phones pose a health hazard?
The available scientific evidence does not show that any health problems are
associated with using wireless phones. There is no proof, however, that wireless
phones are absolutely safe. Wireless phones emit low levels of radiofrequency
energy (RF) in the microwave range while being used. They also emit very low levels
of RF when in the stand-by mode. Whereas high levels of RF can produce health
effects (by heating tissue), exposure to low level RF that does not produce heating
effects causes no known adverse health effects. Many studies of low level RF
exposures have not found any biological effects. Some studies have suggested that
some biological effects may occur, but such findings have not been confirmed by
additional research. In some cases, other researchers have had difficulty in
reproducing those studies, or in determining the reasons for inconsistent results.
What is FDA's role concerning the safety of wireless phones?
Under the law, FDA does not review the safety of radiation-emitting consumer
products such as wireless phones before they can be sold, as it does with new drugs
or medical devices. However, the agency has authority to take action if wireless
phones are shown to emit radiofrequency energy (RF) at a level that is hazardous to
the user. In such a case, FDA could require the manufacturers of wireless phones to
notify users of the health hazard and to repair, replace or recall the phones so that
the hazard no longer exists.
Although the existing scientific data do not justify FDA regulatory actions, FDA has
urged the wireless phone industry to take a number of steps, including the following:
• Support needed research into possible biological effects of RF of the type
emitted by wireless phones;
• Design wireless phones in a way that minimizes any RF exposure to the user that
is not necessary for device function; and
• Cooperate in providing users of wireless phones with the best possible
information on possible effects of wireless phone use on human health.
FDA belongs to an interagency working group of the federal agencies that have
responsibility for different aspects of RF safety to ensure coordinated efforts at
the federal level. The following agencies belong to this working group:
• National Institute for Occupational Safety and Health
• Environmental Protection Agency
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• Federal Communications Commission
• Occupational Safety and Health Administration
• National Telecommunications and Information Administration
The National Institutes of Health participates in some interagency working group
activities, as well.
FDA shares regulatory responsibilities for wireless phones with the Federal
Communications Commission (FCC). All phones that are sold in the United States
must comply with FCC safety guidelines that limit RF exposure. FCC relies on FDA
and other health agencies for safety questions about wireless phones.
FCC also regulates the base stations that the wireless phone networks rely upon.
While these base stations operate at higher power than do the wireless phones
themselves, the RF exposures that people get from these base stations are typically
thousands of times lower than those they can get from wireless phones. Base stations
are thus not the primary subject of the safety questions discussed in this document.
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 studies 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 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. 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
provides 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
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.
What steps can I take to reduce my exposure to radiofrequency 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 radiofrequency
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energy (RF). 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 do 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.
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
radiofrequency energy (RF), 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.
Do hands-free kits for wireless phones reduce risks from exposure to RF emissions?
Since there are no known risks from exposure to RF emissions from wireless phones,
there is no reason to believe that hands-free kits reduce risks. Hands-free kits can
be used with wireless phones for convenience and comfort. These systems reduce
the absorption of RF energy in the head because the phone, which is the source of
the RF emissions, will not be placed against the head. On the other hand, if the phone
is mounted against the waist or other part of the body during use, then that part
of the body will absorb more RF energy. Wireless phones marketed in the U.S. are
required to meet safety requirements regardless of whether they are used against
the head or against the body. Either configuration should result in compliance with
the safety limit.
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Do wireless phone accessories that claim to shield the head from RF
radiation work?
Since there are no known risks from exposure to RF emissions from wireless phones,
there is no reason to believe that accessories that claim to shield the head from
those emissions reduce risks. Some products that claim to shield the user from RF
absorption use special phone cases, while others involve nothing more than a
metallic accessory attached to the phone. Studies have shown that these products
generally do not work as advertised. Unlike "hand-free" kits, these so-called "shields"
may interfere with proper operation of the phone. The phone may be forced to boost
its power to compensate, leading to an increase in RF absorption. In February 2002,
the Federal trade Commission (FTC) charged two companies that sold devices that
claimed to protect wireless phone users from radiation with making false and
unsubstantiated claims. According to FTC, these defendants lacked a reasonable
basis to substantiate their claim.
How does FCC Audit Cell Phone RF?
After FCC grants permission for a particular cellular telephone to be marketed, FCC will
occasionally conduct “post-grant” testing to determine whether production versions
of the phone are being produced to conform with FCC regulatory requirements. The
manufacturer of a cell phone that does not meet FCC’s regulatory requirements
may be required to remove the cell phone from use and to refund the purchase price
or provide a replacement phone, and may be subject to civil or criminal penalties.
In addition, if the cell phone presents a risk of injury to the user, FDA may also
take regulatory action. The most important post-grant test, from a consumer’s
perspective, is testing of the RF emissions of the phone. FCC measures the Specific
Absorption Rate (SAR) of the phone, following a very rigorous testing protocol.
As is true for nearly any scientific measurement, there is a possibility that the test
measurement may be less than or greater than the actual RF emitted by the phone.
This difference between the RF test measurement and actual RF emission is because
test measurements are limited by instrument accuracy, because test measurement
and actual use environments are different, and other variable factors. This inherent
variability is known as “measurement uncertainty.” When FCC conducts post-grant
testing of a cell phone, FCC takes into account any measurement uncertainty to
determine whether regulatory action is appropriate. This approach ensures that
when FCC takes regulatory action, it will have a sound, defensible scientific basis.
FDA scientific staff reviewed the methodology used by FCC to measure cell phone
RF, and agreed it is an acceptable approach, given our current understanding of the
risks presented by cellular phone RF emissions. RF emissions from cellular phones
have not been shown to present a risk of injury to the user when the measured SAR
is less than the safety limits set by FCC (an SAR of 1.6 w/kg). Even in a case where
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the maximum measurement uncertainty permitted by current measurement
standards was added to the maximum permissible SAR, the resulting SAR value
would be well below any level known to produce an acute effect. Consequently,
FCC’s approach with measurement uncertainty will not result in consumers being
exposed to any known risk from the RF emitted by cellular telephones.
FDA will continue to monitor studies and literature reports concerning acute
effects of cell phone RF, and concerning chronic effects of long-term exposure to
cellular telephone RF (that is, the risks from using a cell phone for many years). If
new information leads FDA to believe that a change to FCC’s measurement policy
may be appropriate, FDA will contact FCC and both agencies will work together to
develop a mutually-acceptable approach.
Updated July 29, 2003
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