Generation of Hydrogen Peroxide, Superoxide Anion and the Hydroxyl Free Radical from Polyphenols and Active Benzene Metabolites: Their Possible Role in Mutagenesis. 
Benzene is strongly suspected of being an animal and human carcinogen, but the mechanisms by which it induces tumors of lymphoid and hematopoietic organs are unknown.  Production of active oxygen species from benzene metabolites [hydroquinone (HQ), catechol and 1,2,4-benzenetriol (1,2,4-BT) and related polyphenols (resorcinol, pyrogallol and phloroglucinol)] are investigated.  Pyrogallol and 1,2,4-BT can produce H(2)O(2), O(-)(2) and (.)OH simultaneously, and have powerful mutagenic potential.  Resorcinol and phloroglucinol cannot produce all of the active oxygen species, and show no mutagenic effects.  Catechol can produce H(2)O(2), but cannot produce O(-)(2) and (.)OH, and has no mutagenic activity.  These data strongly support the hypothesis that benzene metabolites can cause mutagenicity via the generation of oxygen radicals.  Although HQ produces H(2)O(2) only, and less than produced by pyrogallol and 1,2,4-BT, the mutagenicity of HQ is higher.  The results indicate that HQ may act via another mechanism to cause mutagenicity.  In the presence of trace metal ions, the reactivity of polyphenols is increased.  The biological significance of these phenomena are investigated and discussed.  Copyright 1994 S. Karger AG, Basel