ELECTROMAGNETIC-FIELDS AND MALE BREAST-CANCER

The aetiology of male breast cancer is still considered to be rather u nclear. Epidemiological studies have recently shown an excess risk of male breast cancer in ''electrical workers'' with potential exposure t o electromagnetic (EM) fields. Interest on the possible association be tween pineal function and breast cancer has come into focus. The pinea l hormone melatonin has been shown to reduce the incidence of experime ntally-induced breast cancer in rats, the hormone is oncostatic and cy totoxic to breast, ovarian, and bladder cancer cell lines in vitro. Tr eatment of cancer patients with orally administered melatonin has been tried. Pineal function in humans is suppressed by light-at-night (LAN ). Animal studies have shown that exposure to 60-Hz electric fields ma y also suppress the nocturnal rise in pineal melatonin production in a dult rats. Breast cancer is the leading cause of cancer death among wo men in the industrialised world. No good explanation has so far been p rovided for the increased incidence of this site during the last decad es, although changes in fertility factors have had some effect. If new epidemiological and experimental data give support to the hypothesis that exposure to LAN and EM fields may increase breast cancer risk, th is may have regulatory and political consequences for future use of el ectric power.