UTStarcom PN-820 - Manual (Page 273)

271
C
H
10
1. 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.
2. 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
• Federal Communications Commission
• Occupational Safety and Health Administration
• National Telecommunications and Information Administration
The National Institutes of Health participates in some inter-agency 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 subject of the safety questions
discussed in this document.
FDA CONSUMER UPDATE
3. What kinds of phones are the subject of this update?
The term “wireless phone” refers here to hand-held wireless phones with built-in antennas,
often called “cell,” “mobile,” or “PCS” phones.
These types of wireless phones can expose the user to measurable radiofrequency energy
(RF) because of the short distance between the phone and the user’s head. These RF
exposures are limited by Federal Communications Commission safety guidelines that were
developed with the advice of FDA and other federal health and safety agencies. When
the phone is located at greater distances from the user, the exposure to RF is drastically
lower because a person’s RF exposure decreases rapidly with increasing distance from
the source. The so-called “cordless phones,” which have a base unit connected to the
telephone wiring 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 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 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 predisposed 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
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 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 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 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. 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 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.