Cell Phone Use Not Likely Linked to Brain Cancer
Extensive media attention has focused on the health implications of the use of cellular telephones. The concern has been based primarily on anecdotal evidence that the microwave-frequency signals these phones transmit could cause brain cancer. One recent investigation a National Cancer Institute (NCI) study reported this month in the New England Journal of Medicine found that it is highly unlikely that the use of cell phones increases the risk of brain tumors.
Between 1994 and 1998, the researchers examined 782 patients with confirmed brain tumors in Phoenix, Boston, and Pittsburgh hospitals. The patients were divided into groups by tumor type and compared with 799 controls admitted to these hospitals for other conditions. Researchers collected data about cell phone use through personal interviews with each of the study participants. The interviewer asked when the participants first began using a hand-held cell phone, when they last used one, how often and how frequently they used these phones, the duration of a typical cell phone call, and with which hand they usually held the handset.
Cell phone use was not significantly associated with any of the tumor types. The percentage of controls (29%) who reported using a cell phone more than five times was almost identical to the percentage of brain cancer patients who reported using them (22-31% grouped by tumor type). Risk was not higher among regular users who began using cell phones earlier, nor did it rise significantly with the increased duration of use, frequency of use, or total overall use. In addition, tumors did not occur disproportionately on the side of the head on which the cell phone was more frequently used.
The NCI authors point out, however, that since cell phones were introduced only 20 years ago, and were not widely used until the mid-1990s, the possibility of harm associated with long-term, heavy use cannot be predicted. They also note that technological advances may alter the design of future cell phones, affecting cancer risk. Thus, the connection between cancer and cell phone use is likely to be revisited in years to come.
January 2001 Update