Xenobiotics

Synonyms

Exobiotics; Foreign substances

Definition

Xenobiotics are chemicals found but not produced by organisms or the environment. Some naturally occurring chemicals (endobiotics) become xenobiotics when present in the environment at excessive concentrations. The “xeno” in “xenobiotics” comes from the Greek word xenos meaning guest, friend, or foreigner.

Characteristics

Origin of Xenobiotics

Xenobiotics are mostly produced by human activities and excite public awareness due to their ability to interact with the living environment. Some organisms may also form them as a part of their defense system, e.g., mycotoxins, bacterial and herbal toxins, etc., and xenobiotics become harmful when entering the food chain. Contemporary human exposure to xenobiotics is unavoidable, as they are omnipresent. Exposure to some xenobiotics is voluntary because of their anticipated beneficiary effects on human health (e.g., drugs, antibiotics, dietary supplements like antioxidants, etc.). Daily use of...