An Assessment of Current Standards for Selenium in Drinking Water

Abstract

ABSTRACTSelenium is a trace metal naturally occurring in soils derived from some sedimentary rocks. Upon oxidation to the selenate ion, it can percolate to ground water and be assimilated by plants. Effects upon human health have not been clearly established—a low selenium diet is beneficial, while high doses can produce undesirable physical manifestations. Neither extreme dietary deficiency nor toxicity is apparent in the human population of the United States. The maximum contaminant level of 10 μg/1 adopted in the National Interim Primary Drinking Water Regulations is not justified by recent studies and should not be enforced by the Environmental Protection Agency without new scientific evidence demonstrating that naturally occurring selenium is a health hazard.0