Cellular-Telephone Use and Brain Tumors

Hand-held cellular telephones were introduced to the U.S. market in 1984 1 but were not widely used until the mid-1990s. By early 2000, the number of subscribers to cellular-telephone services had grown to an estimated 92 million in the United States and 500 million worldwide. 2 , 3 Some concern has arisen about adverse health effects, especially the possibility that the low-power microwave-frequency signal transmitted by the antennas on handsets might cause brain tumors or accelerate the growth of subclinical tumors. 4 – 8 It is generally agreed that the heating of brain tissue by cellular telephones is negligible, and that any carcinogenic effect would . . .