British scientists participating in the Mobile Telecommunications and Health Research program also have weighed in. As part of the initiative, Lawrence Challis, emeritus professor of physics at the University of Nottingham, led a panel in England that reviewed 23 studies on cell phone use and health effects.
The panel concluded that radio-frequency radiation from cell phones poses no short-term health risk.
But Challis says that among the few studies that included people who had been using cell phones for more than a decade, there is uncertainty. Some studies identified a very slight increase in the number of brain cancers among cell phone users.
"There are slight hints of something" for people who have used cell phones for more than 10 years," says Challis. "But they are not totally convincing hints. All they are, are suggestions."
It's possible the cancers were due to chance.