Mortality in a population with long-term exposure to inorganic selenium via drinking water

We analyzed the 1986-1997 mortality in a cohort of 2065 residents of an Ita lian municipality which had been exposed to drinking water with a high cont ent of inorganic selenium over a long period of time, and compared it with mortality in the remainder of the municipal population. Mortality from mali gnant neoplasms increased [standardized mortality ratio (SMR) 1.17, 95% con fidence interval (CI) 0.96-1.42], mainly due to an excess mortality from me lanoma and colorectal cancer in both sexes, kidney cancer in men, and lymph oid malignancies in women. Overall cardiovascular mortality changed little (SMR 1.05, 95% CI 0.89-1.23), despite the higher cerebrovascular mortality (SMR 1.43, 95% CI 1.03-1.93). Coronary disease mortality slightly decreased (SMR 0.87,95% CI 0.63-1.16), due to a low mortality among women. We also n oted an excess mortality from Parkinson's disease in men and from motor neu ron disease in women. Evaluation of these findings is, however, hampered by the lack of information about potential lifestyle confounders, the fact th at the exposure could only be characterized by a simple dichotomization, an d the inconsistencies of most estimates between the two sexes. (C) 2000 Els evier Science Inc. All rights reserved.