User's Manual

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 it is largely unknown what

the results of such studies mean for human health and safety. Three large epidemiology studies have been

published since December 2000. These studies investigated possible associations between the use of wireless

phones and primary brain cancer (glioma, meningioma, acoustic neuroma, other brain tumors, and salivary gland

tumors), leukemia, or other types of cancer. None of the studies demonstrated the existence of any harmful health

effects from wireless phone RF exposures. However, none of the studies can provide absolute findings about

long-term exposuressince the average period of phone use in these studies was approximately three years.

4. What kinds of phones are the subjects of this update?

Here the term “wireless phone” refers to handheld wireless phones with built-in antennas, often called “cell”,

“mobile”, or “PCS” phones. These types of wireless phones can expose the user to measurable Radio Frequency

(RF) energy because of the short distance between the phone and the user‟s head. These RF exposures are

limited by FCC safety guidelines that were developed with the advice of the 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

reduced due to a person's RF exposure rapidly decreasing 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, thus producing RF exposures far below the FCC safety limits.

5. 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 concerns 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 implemented new research programs around the world. The project has also

resulted in 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

conduct 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