OVERALL MORTALITY OF CELLULAR TELEPHONE CUSTOMERS

Unlike mobile cellular telephones, in which the antenna is not part of the handset, a portable cellular telephone exposes the user's head to radio frequency energy transmitted from the antenna. This exposure ha s prompted concerns about potential biological effects, including brai n cancer. As a first step in a record-based mortality surveillance of cellular telephone customers, we report on overall mortality of a coho rt of more than 250,000 portable and mobile telephone customers during 1994. We found age specific rates to be similar for users of the two types of telephones. For customers with accounts at least 3 years old, the ratio of mortality rates in 1994 for portable telephone users, co mpared with mobile telephone users, was 0.86 (90% confidence interval = 0.47-1.53).