Public health and regulatory considerations of the Safe Drinking Water Act.

This paper provides an overview of the public health and economic issues associated with drinking water quality regulations in the United States. A historic perspective is provided by the use of filtration and chlorine disinfection, and of public health laws from the early 20th century up to passage of the Safe Drinking Water Act (SDWA), in 1974. The contaminants regulated under the Act, and the 1986 Amendments to the SDWA, are evaluated according to health endpoint, related issues in risk assessment, and the cost of complying with associated regulations. Risk-cost and benefit-cost analyses are offered for carcinogens, systemics, and pathogens. The paper describes the evolution of public health issues from the initial focus on waterborne infectious diseases to concerns over chemical contaminants, and the recent reemergence of microbials as the high-priority public health concern.