RT Book, Section A1 Faustman, Elaine M. A2 Klaassen, Curtis D. SR Print(0) ID 1158496116 T1 Risk Assessment T2 Casarett & Doull’s Toxicology: The Basic Science of Poisons, 9th edition YR 2019 FD 2019 PB McGraw-Hill Education PP New York, NY SN 9781259863745 LK accessbiomedicalscience.mhmedical.com/content.aspx?aid=1158496116 RD 2024/03/29 AB In the 1970s U.S. Congress established a basic plan for environmental laws that authorized regulatory actions to protect public health and the environment. These science-based actions provided the foundation for environmental and human health risk assessment. Recent updates and revisions of these laws including the 2016 Frank R. Lautenberg Chemical Safety from the 21st Century Act, which modified the 1976 Toxic Substance Control Act, have reinforced the need for toxicology evaluation. Toxicological research and toxicity testing constitute the scientific core of risk assessment, which is used for evaluating potential adverse health impacts from chemical exposures. Considerations for risk evaluation were not new, since for decades the American Conference of Governmental Industrial Hygienists (ACGIH) set threshold limit values for occupational exposures and the U.S. Food and Drug Administration (FDA) established acceptable daily intakes (ADIs) for pesticide residues and food additives. In 1958, the U.S. Congress instructed the FDA in the Delaney Clause to prohibit the addition of all substances found to cause cancer in animals or humans to the food supply. Pragmatically, this policy allowed food sources that had nondetectable levels of these additives to be declared “safe.” As advances in analytical chemistry revealed that “nondetects” were not equivalent to “not present,” regulatory agencies were forced to develop “tolerance levels” and “acceptable risk levels.” Risk assessment methodologies blossomed in the 1970s with the rising need to address these issues and to provide a common framework for considering human and ecological health effects (Albert, 1994).