Dr. Michael H. Dong holds a Doctor of Public Administration (Dr.P.A.) degree in (environmental) health policy from the University of Southern California and a Doctor of Philosophy (Ph.D.) degree in environmental epidemiology from the University of Pittsburgh. He has also earned a Master of Public Health (M.P.H.) in environmental/nutritional sciences from the University of California at Los Angeles (UCLA), a B.Sc. in biochemistry from the University of California at Riverside, and a second B.Sc. in forensic science from the California State University at Sacramento (CSUS). For many years until his recent retirement, He was a full member (later an emeritus) of the American College of Nutrition, a full member of the (American) Society of Toxicology, a Certified Nutrition Specialist (CNS), and a Diplomate of the American Board of Toxicology (DABT). Dr. Dong worked for 25 years as a regulatory toxicologist for the state of California. Prior to his state government employment, Dr. Dong was on military active duty for several years as a U.S. Public Health Service Commissioned Corps officer stationed at the U.S. Food and Drug Administration. Earlier he also served for several years as a U.S. Army Medical Service Corps officer with various assignments working as a research, nutritional, or clinical biochemist. Between the two U.S. military services, He worked for a year as an occupational toxicologist as well as an environmental epidemiologist at the U.S. Occupational Safety and Health Administration. For four years from 2005 to 2009, Michael served as one of the dozen board members of the American Board of Toxicology (ABT) and chaired the ABT certification examination committee during his fourth year of service there. From 2006 to 2008, he served as a voting member of the Scientific Advisory Committee on Alternative Toxicological Methods (SACATM) for the U.S. National Institute of Environmental Health Sciences. He also served on the editorial board for the two international journals Environmental Geochemistry and Health from 2004 through 2015, and Human and Ecological Risk Assessment from 2013 through 2016. From 2008 through 2014, he was an adjunct lecturer teaching the environmental toxicology course for the Department of Environmental Studies at CSUS. His most recent publication prior to this Fourth Edition was titled "The Health Risk Assessment Performed in California for the Herbicide Simazine: A Case Study" (Hum. Ecol. Risk Assess. 2015, 21:1496-1517).