Benzo[a]pyrene
![](/Images/godic/202412/24/Benzo-a-pyrene.svg0348.png")
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![Benzo[a]pyrene, showing the base pyrene ring and numbering and ring fusion locations according to IUPAC nomenclature of organic chemistry.](/Images/godic/202412/24/Benzo(a)pyrene_numbered0348.png")
![Metabolism of benzo[a]pyrene yielding the carcinogenic benzo[a]pyren-7,8-dihydrodiol-9,10-epoxide.](/Images/godic/202412/24/Benzo(a)pyrene_metabolism.svg0348.png")
Benzo[a]pyrene is a polycyclic aromatic hydrocarbon found in coal tar with the formula C20H12. Its metabolites are mutagenic and highly carcinogenic, and it is listed as a Group 1 carcinogen by the IARC. The compound is one of the benzopyrenes, formed by a benzene ring fused to pyrene, and is the result of incomplete combustion at temperatures between 300 °C (572 °F) and 600 °C (1,112 °F).