Specifications

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Reference
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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 fre-
quencies, has not been questioned.
How much evidence is there that hand-held mobile phones might be
harmful?
Briefly, there is not enough evidence to know for sure, either way; however, research
efforts are ongoing. The existing scientific evidence is conflicting and many of the
studies that have been done to date have suffered from flaws in their research meth-
ods. Animal experiments investigating the effects of RF exposures characteristic of
mobile phones have yielded conflicting results. A few animal studies, however, have
suggested that low levels of RF could accelerate the development of cancer in labora-
tory animals. In one study, mice genetically altered to be predisposed to developing
one type of cancer developed more than twice as many such cancers when they were
exposed to RF energy compared to controls. There is much uncertainty among scien-
tists about whether results obtained from animal studies 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 that showed increased tumor development used
animals that had already been treated with cancer-causing chemicals, and other
studies exposed the animals to the RF virtually 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:
1. 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 associa-
tion 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 average length of mobile phone expo-
sure in this study was less than three years.
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 cellu-
lar 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 radia-
tion) 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 heat-
ing 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 radia-
tion 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 dis-
tance 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.
FDA
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