n.
Study of poison s and their effects, particularly on living systems.
It overlaps with biochemistry , histology , pharmacology , pathology , and other fields. Its functions have expanded from identifying poisons and searching for treatments to include forensic toxicology (see forensic medicine ) and testing and detection of a fast-growing number of new potentially toxic substances used in workplaces, in agriculture (e.g., insecticide s, other pesticide s, fertilizers), in cosmetic s, as food additives, and as drug s (see drug poisoning ). Perhaps the area of largest expansion is the study of toxic waste in the air, water, and soil, including chlorofluorocarbon s, acid rain , dioxin , and radioactive isotope s.