Cell Phone Health Studies Continue

Explosive Growth, Unknown Consequences

More than 90 million Americans use mobile phones. The number is growing exponentially as prices drop and wireless Web access becomes more widely available. But little is known about the health effects of radio frequency emissions on cell phone users.

An October 1999 FDA consumer update on mobile phones notes: "It is well known that high levels of [radio frequency] can produce biological damage through heating effects (this is how your microwave oven is able to cook food). However, it is not know whether, to what extent, or through what mechanism, lower levels of [radio frequency] might cause adverse health effects as well."

The FDA adds, "Although some research has been done to address these questions, no clear picture of the biological effects of this type of radiation has emerged to date."

Prior research offers conflicting evidence, according to the FDA. A few animal studies suggest that low-level radio frequency exposure accelerates the development of cancer in laboratory animals. But scientists are uncertain whether that study's results apply to cell phone use.

Repetitive experiments are necessary to show effects can be duplicated, the working group says. For scientific legitimacy, data must be published and then reproduced by other groups.

The FDA is developing research recommendations based on the ideas and concerns of the working group, says Russell D. Owen, chief of the FDA's Radiation Biology branch.

Warning Labels Appear

Another governmental agency is also tracking the issue. The Federal Communications Commission monitors radio frequency emissions, called specific absorbed radiation (SAR). In 1996, the FCC set a limit for the radiation level of cell phones at 1.6 watts per kilogram (or 2.2 pounds) of human tissue.

The industry association recently required all cell phones submitted for certification after August 1 to include SAR data inside their packaging. Cell phones with SAR information will be on the market in three to six months. In the meantime, the FCC Web site has information on how consumers can determine the SAR level of their phones.

All parties are awaiting more conclusive research. In the interim, some scientists recommend using an ear piece with your cell phone to distance the antenna from your head. But that may simply mean radio frequency emissions are directed to another part of your body.