Encyclopedia of Cancer

Living Edition
| Editors: Manfred Schwab


  • Pavel Soucek
Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-27841-9_6276-2



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.


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...


Interindividual Variability Grapefruit Juice Metabolizer Phenotype Constitutive Androstane Receptor Poor Metabolizer Phenotype 
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© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.Toxicogenomics Unit, Center for Toxicology and Health SafetyNational Institute of Public HealthPragueCzech Republic