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 known--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), considered 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 questions, no clear picture of the biological
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 any 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 conversation. 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 person'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 rapidly
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 operate at far lower power levels and frequencies, has not been
questioned.
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