toxicology, study of poisons, or toxins, from the standpoint of detection, isolation, identification, and determination of their effects on the human body. Toxicology may be considered the branch of pharmacology devoted to the study of the poisonous effects of drugs. It is also a division of forensic medicine concerned with the detection of the criminal use of poisons.

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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