Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of exposure is not known.

The amount of time people spend on cell phones has increased and will be taken into consideration during current and future studies. Research will continue to investigate whether there is a relationship between slow-growing tumors in the brain or elsewhere with long-term cell phone use.

WHAT WE KNOW ABOUT CELL PHONE USE

Cell phones use low levels of radiofrequency energy (RF). Exposures to low levels of RF from cell phones have not been found to cause health problems.

The U.S. Food and Drug Administration (FDA) and the Federal Communications Commission (FCC) have developed guidelines that limit the amount of radiofrequency energy that cell phones are allowed to give off.

The RF exposure from cell phones is measured in Specific Absorption Rate (SAR). The SAR measures the amount of energy absorbed by the body. The SAR permitted in the United States is 1.6 watts per kilogram (1.6 W/kg).

According to the FCC, this amount is much lower than the level shown to cause any changes in laboratory animals. Every cell phone manufacturer is required to report the RF exposure of each of its phone models to the FCC.

CHILDREN AND CELL PHONES

Generally, cell phone studies have involved adults aged 18 or older. Most children didn't use cell phones until the mid-1990s. This leaves the effects of cell phone use on children unclear.

Other national governments have recommended that children be discouraged from using cell phones. In December 2000, the British government handed out pamphlets that recommended reducing the amount of time children spend on a cell phone. However, there was no scientific evidence confirming or denying a health risk.

CELL PHONES AND DRIVING

The risk of being in a car accident while talking on a cell phone is higher than any risk for cancer.

Regulatory organizations such as the National Highway Traffic Safety Administration (NHTSA) and the National Safety Council (NSC) emphasize that a cell phone conversation distracts the driver. Therefore, having a hands-free phone may not reduce the chance of an accident. There is considerable controversy over these safety issues.

New laws regarding cell-phone use while driving have passed or are being reviewed by individual states. For example, New York has a law prohibiting the use of cell phones while driving. Other states have some restrictions.

Clearly, there are some dangers associated with cell phone use and driving. Reduce the amount of time you spend driving and talking on the phone. Avoid stressful conversations while on the road, and, if possible, pull over to make your call.

REDUCING RISKS

Although health problems related to long-term use are thought to be unlikely, you can take some steps to limit your potential risk.

• Have lengthy phone conversations on a conventional telephone (landline) instead of your cell phone.
• Change to a cell phone that has its antenna outside the vehicle.
• Use a headset and place the phone away from your body.
• Find out how much SAR energy your cell phone gives off.

Cancer and cell phones

Updated by: Daniel B. Hoch, PhD, MD, Assistant Professor of Neurology, Harvard Medical School, Department of Neurology, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.