Reproductive outcomes in a population exposed long-term to inorganic selenium via drinking water

Despite being an essential element in mammals and lower animals at very low doses, selenium is recognized as a teratogen and a growth-inhibiting subst ance in several animal species. Some inorganic selenium compounds have also been shown to be mutagenic and pro-oxidant: however, very little is known about their effects on human reproduction. Between 1972 and 1988, a few tho usand residents in the municipality of Reggio Emilia, northern Italy, were accidentally exposed to drinking water with unusually high levels of inorga nic selenium (selenate), range 7-9 mu g/l, through a local public water sup ply system. We found no deleterious effect on overall body weight and lengt h of newborns and stillborns delivered by 18 women previously exposed to hi gh-selenium tapwater, Rates of spontaneous abortions, however, were increas ed slightly (RR = 1.73; 95% CI = 0.62-4.80), compared with rates among unex posed women from the same municipality. From 1980 through 1988 the prevalen ce of congenital malformations at birth among the exposed population was si milar to that expected, but estimates were imprecise owing to small numbers . Results do not suggest marked effects on human reproduction from chronic exposure to selenate in drinking water at < 10 mu g/l. (C) 2000 Elsevier Sc ience B.V. All rights reserved.