Robert A. Howd is Chief of the Water Toxicology Section in the Office of Environmental Health Hazard Assessment of the California EPA, supervising the production of California Public Health Goals for chemicals in drinking water. Dr. Howd has authored or coauthored over fifty formal scientific publications and numerous government reports.

Anna M. Fan is Chief of the Pesticide and Environmental Toxicology Branch, Office of Environmental Health Hazard Assessment, California EPA. Dr. Fan has served on the U.S. EPA Science Advisory Board, Drinking Water Committee; the U.S. EPA Endocrine Disruptors Screening and Testing Advisory Committee; and other national advisory committees. She is an editor of the Journal of Environmental Science and Health, Part C: Environmental Carcinogenesis and Ecotoxicology Reviews.