: the study of poisonous chemicals, drugs, etc., and how a person or other living thing reacts to them
Study of poisons 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., insecticides, other pesticides, fertilizers), in cosmetics, as food additives, and as drugs (see drug poisoning). Perhaps the area of largest expansion is the study of toxic waste in the air, water, and soil, including chlorofluorocarbons, acid rain, dioxin, and radioactive isotopes.
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