Scientists have been probing the possible link between cell phones and cancer for several years. The U.S. government concern was triggered by two industry-sponsored studies that the FDA said required additional research. One found an association between cell phone use and a rare type of brain tumor. In advisories to consumers, the FDA has stressed that there is so far no scientific basis for concluding that cell phones are unsafe - or that they are safe.
Cell phones use microwave signals to transmit data or human voices.
The major difference between cell phones and microwave ovens is the amount of power that propels the signal. The key question is whether the low level of microwave radiation used by a cell phone also can cause harm. In the study, researchers identified 420,095 Danes who used cell phones between 1982 and 1995. Then they compiled a separate list of those in that group who ever had cancer. But the scientists found there were fewer overall incidents of cancer among the cell phone users than among all Danes.