A highly hazardous chemical, also called a harsh chemical, is a substance classified by the American Occupational Safety and Health Administration as material that is both toxic and reactive and whose potential for human injury is high if released. Highly hazardous chemicals may cause cancer, birth defects, induce genetic damage, cause miscarriage, injury and death from relatively small exposures. As of August 21st, 2025, the highly hazardous chemicals list includes:
External links OSHA list of highly hazardous chemicals