GASTROINTESTINAL CANCER MORTALITY OF WORKERS IN OCCUPATIONS WITH HIGHASBESTOS EXPOSURES

Asbestos, which is a well-known risk factor for lung cancer and malign ant mesothelioma, has also been suggested as a gastrointestinal (GI) c arcinogen. This study was conducted to assess the relationship between high asbestos exposure occupations and the occurrence of GI cancel: D eath certificate data were analyzed from 4,943,566 decedents with info rmation on occupation and industry from 28 states from 1979 through 19 90. Elevated proportionate mortality ratios (PMRs) for mesothelioma we re used to identify occupations potentially having many workers expose d to asbestos. All PMRs were age-adjusted and sex- and race-specific. The PMRs for GI cancers in white males were then calculated for these occupations after excluding mesothelioma, lung cancer, and non-maligna nt respiratory disease from all deaths. We identified 15,524 cases of GI cancer in the 12 occupations with elevated PMRs for mesothelioma. W hen these occupations were combined, the PMRs for esophageal, gastric, and colorectal cancer were significantly elevated at 108 (95% confide nce interval = 107-110), 110 (106-113), and 109 (107-110), respectivel y. Esophageal cancer was elevated in sheet metal workers and mechanica l workers. Gastric cancel was elevated in supervisors in production an d managers. Colorectal cancel was elevated in mechanical and electrica l and electronic engineers. However high exposure occupations like ins ulation, construction painter supervisors, plumbers, furnace operators , and construction electricians showed no elevations of GI cancers. In conclusion, this death certificate study supports an association betw een asbestos exposure and some GI cancer, however the magnitude of thi s effect is very small. (C) 1997 Wiley-Liss, Inc.