Toxicology is the scientific study of adverse effects that occur in living organisms because of chemicals. It involves perceptive and reporting symptoms, mechanisms, detection and treatment of poisonous substances, specially respect to the poisoning of humans. It includes environmental agents and chemical compounds found in nature, likewise as pharmaceutical compounds that are synthesized for medical use by humans.

Clinical toxicology is the branch of science which deals with the removing of the poisonous substances or harmful chemicals from the body of any organism. Clinical toxicologists are the people who are expertized in the field of detoxification. Medical toxicology is a part of the toxicology and deals with the removal of the harmful toxins from the body. The poisoning may be intentional or unintentional but the adverse effects may lead to the lethal damage to the organism. Both clinical and medical toxicologists play an important role in detoxification.

Environmental toxicology is the multidisciplinary branch of science with links the environment and the toxic chemicals. The reason for the environmental toxicity is enormous and they may be the pollution which is of different types and the industrial waste. The harmful toxic substances released from the industries and the industrial waste result in the environmental toxicity. Ecotoxicology is the recent emerging concept in the environmental toxicology.

Food and nutritional toxicology is the part of toxicology which deals with the various food substances which cause the toxicity to the body. The food toxicity may be a result of the pesticides and herbicides used during the process of cultivation. The nutritional toxicity may also result in the toxic response to the body. Nutritional toxicology is a speciality that combines the backgrounds and research approaches of nutrition toxicology.

Forensic toxicology is the use of toxicology and other disciplines such as analytical chemistry, pharmacology and clinical chemistry to aid medical or legal investigation of death, poisoning, and drug use. The primary concern for forensic toxicology is not the legal outcome of the toxicological investigation or the technology utilized, but rather the obtainment and interpretation of results. A toxicological analysis can be done to various kinds of samples. Determining the substance ingested is often complicated by the body's natural processes ADME, as it is rare for a chemical to remain in its original form once in the body.