Arsenic in Drinking Water

The U.S. Environmental Protection Agency (EPA) has been considering a more stringent regulation of arsenic in water. A significant reduction in the maximum contaminant level (MCL) could increase compliance costs for water utilities. This book discusses the adequacy of the current EPA MCL for protecting human health in the context of stated EPA policy and provides an unbiased scientific basis for deriving the arsenic standard for drinking water and surface water.Arsenic in Drinking Water evaluates epidemiological data on the carcinogenic and noncarcinogenic health effects of arsenic exposure of Taiwanese populations and compares those effects with the effects of arsenic exposure demonstrated in other countries—including the United States.The book also reviews data on toxicokinetics, metabolism, and mechanism and mode of action of arsenic to ascertain how these data could assist in assessing human health risks from arsenic exposures. This volume recommends specific changes to improve the toxicity analyses and risk characterization. The implications of the changes for EPA's current MCL for arsenic are also described.Table of ContentsFront MatterExecutive Summary1 Introduction2 The U.S. Environmental Protection Agency's 1988 Risk Assessment for Arsenic3 Chemistry and Analysis of Arsenic Species in Water and Biological Materials4 Health Effects of Arsenic5 Disposition of Inorganic Arsenic6 Biomarkers of Arsenic Exposure7 Mechanisms of Toxicity8 Variation in Human Sensitivity9 Essentiality and Therapeutic Uses10 Statistical Issues11 Risk CharacterizationAddendum to Chapter 9Addendum to Chapter 10