Cellular Phone Information Sheet

Kelly Classic, Medical Health Physicist

The term cellular phone refers here to handheld wireless phones with built-in antennas, often called "cell," "mobile," or "PCS" (personal communications systems) phones. These types of wireless phones can expose the user to radiofrequency (RF) energy because of the short distance between the phone and the user's head. These RF exposures are limited by Federal Communications Commission (FCC) safety guidelines that were developed with the advice of Food and Drug Administration (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.

Cellular phone technology, including PCS, is designed to be safe both for users and for people living near base-station antennas. Cellular phones are actually small radios that transmit signals to and from base-station antennas located on towers or buildings in the nearby neighborhood. Cellular phones use low-power radio signals, even weaker than CB, police, or fire radios. The American National Standards Institute (ANSI) sets safety standards for human exposure to RF electromagnetic energy in the United States. ANSI conservatively set its maximum permissible exposure levels for RF energy at one-tenth (or less) of the threshold for human health effects. The maximum permissible exposure levels for protection against RF energy recommended by ANSI are comparable to those set in other countries. Government agencies recognize and generally accept the ANSI RF safety standard (ANSI/IEEE C95.1).

The FCC regulates cellular-phone technology. The FDA, the Occupational Safety and Health Administration (OSHA), and many states also have responsibility for RF safety. Cellular phones and cellular-phone base stations have been shown to meet the RF safety standards and to comply with FCC regulations in this area. The consensus of scientific experts is that RF exposure from cellular phones and cellular base-station antennas, meeting the maximum permissible exposure levels set in the safety standards, is safe for all.

The available scientific evidence does not show that any health problems are associated with using wireless phones. There is no proof, however, that cellular phones are absolutely safe. Cellular phones emit low levels of radiofrequency 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 causes no known adverse health effects. Many studies of low-level RF exposures have been conducted but have not found any biological effects. Studies that have suggested there might be biological effects have not been confirmed by additional research.

Three large epidemiology studies have been published since December 2000. These 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.

FDA is working with the US National Toxicology Program and with groups of investigators around the world to ensure that high-priority studies are conducted to address important questions about the effects of exposure to RF energy. 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.

If you are concerned about avoiding potential risks, you can take a few simple steps to minimize your exposure to RF energy. 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.

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.