Users of hand-held cellular telephones are exposed to levels of radiation that are well within national safety standards, according to a study for the National Institutes of Health released Tuesday.
Cellular-phone safety became an issue in February after a St. Petersburg, Fla., man said on CNN's "Larry King Live" that he was suing a manufacturer of cellular-phones and the service provider because his late wife, a frequent cellular-phone user, died of brain cancer. The service provider was later dropped from the suit, which is still pending in a Florida court.The industry reacted immediately by announcing it would pay for government-approved research to determine whether radio waves from cellular phones pose a cancer risk.
The current study, by scientists at the University of Utah, was funded mainly by a grant from the NIH's National Institute of Environmental Health Sciences. McCaw Cellular Communications Inc., the nation's largest cellular-phone service company, provided supplemental funding.
Om Gandhi, chairman of the university's Department of Electrical Engineering, and his colleagues studied 10 hand-held cellular phones from four manufacturers. They investigated specific absorption rates of electromagnetic energy on the head, neck, shoulders and upper torso when a cellular phone is held against the ear.
The amount of radiation absorbed by human tissue is four to five times lower than the levels considered safe by the American National Standards Institute and the Institute of Electrical and Electronics Engineers, the study found.
"Most electromagnetic absorption occurred in the upper part of the ear - consisting mostly of cartilage - and the skin behind it with a rapidly diminishing radio frequency absorption for the nearby tissues in the head," the study said.
The phones in question are free-standing, hand-held devices with antennas close to a user's head.
Car phones with antennas mounted outside the car are not at issue, nor are cordless phones that rest in a base wired into residential phone lines.
Besides the Gandhi study, a series of studies was commissioned by the Cellular Telecommunications Industry Association, the Washington-based trade group that represents the industry.
The Scientific Advisory Group has been discussing over the past several months what kind of research needs to be done to determine whether any health risks could be associated with cellular phones.
On Monday, it announced several areas of study it would pursue.
The research will be tough enough to pass government scrutiny, said Dr. George L. Carlo, an epidemiologist and chairman of the Scientific Advisory Group.
Carlo said scientists are starting from scratch to build the research because existing literature does not speak specifically to the concerns being raised.