The Safe Drinking Water Act directs the U.S. Environmental Protection Agency (EPA) to regulate the quality of drinking water, including its concentration of radon, an acknowledged carcinogen. This book presents a valuable synthesis of information about the total inhalation and ingestion risks posed by radon in public drinking water, including comprehensive reviews of data on the transfer of radon from water to indoor air and on outdoor levels of radon in the United States. It also presents a new analysis of a biokinetic model developed to determine the risks posed by ingestion of radon and reviews inhalation risks and the carcinogenesis process. The volume includes scenarios for quantifying the reduction in health risk that might be achieved by a program to reduce public exposure to radon. Risk Assessment of Radon in Drinking Water, reflecting research and analysis mandated by 1996 amendments to the Safe Drinking Water Act, provides comment on a variety of methods to reduce radon entry into homes and to reduce the concentrations of radon in indoor air and in water. The models, analysis, and reviews of literature contained in this book are intended to provide information that EPA will need to set a new maximum contaminant level, as it is required to do in 2000.