Cellular-telephone use and brain tumors

Background: Concern has arisen that the use of hand-held cellular telephone s might cause brain tumors. If such a risk does exist, the matter would be of considerable public health importance, given the rapid increase worldwid e in the use of these devices. Methods: We examined the use of cellular telephones in a case-control study of intracranial tumors of the nervous system conducted between 1994 and 19 98. We enrolled 782 patients through hospitals in Phoenix, Arizona; Boston; and Pittsburgh; 489 had histologically confirmed glioma, 197 had meningiom a, and 96 had acoustic neuroma. The 799 controls were patients admitted to the same hospitals as the patients with brain tumors for a variety of nonma lignant conditions. Results: As compared with never, or very rarely, having used a cellular tel ephone, the relative risks associated with a cumulative use of a cellular t elephone for more than 100 hours were 0.9 for glioma (95 percent confidence interval, 0.5 to 1.6), 0.7 for meningioma (95 percent confidence interval, 0.3 to 1.7), 1.4 for acoustic neuroma (95 percent confidence interval, 0.6 to 3.5), and 1.0 for all types of tumors combined (95 percent confidence i nterval, 0.6 to 1.5). There was no evidence that the risks were higher amon g persons who used cellular telephones for 60 or more minutes per day or re gularly for five or more years. Tumors did not occur disproportionately oft en on the side of head on which the telephone was typically used. Conclusions: These data do not support the hypothesis that the recent use o f hand-held cellular telephones causes brain tumors, but they are not suffi cient to evaluate the risks among long-term, heavy users and for potentiall y long induction periods. (N Engl J Med 2001;344:79-86.) Copyright (C) 2001 Massachusetts Medical Society.