Mutagenesis by Bulky Addition Products

Benzo(a)pyrene, a chemical produced by internal combusion engines and thus common in the environment, is not itself mutagenic. However, in the mammalian liver, benzo(a)pyrene is metabolized to diol epoxide, which binds covalently to guanine bases, preventing proper base pairing with cytosine bases. Bulky Addition Products such as diol epoxide or Aflatoxin B₁ may result in depurination mutagenesis and are known to be carcinogens.