The epigenetic toxicity of pyrene and related ozonation byproducts containing an aldehyde functional group

Gap junction intercellular communication (GJIC) was used to assess the epigenetic toxicity of pyrene, pure byproducts of pyrene ozonation, and other compounds similar in chemical structure. Byproduct mixtures collected from HPLC were also evaluated using GJIC. Of the 11 pure compounds studied, five inhibited GJIC completely. Two inhibiting compounds contained four rings and were the only compounds studied with greater than three rings. The remaining three compounds contained either two or three rings, and all three contained an aldehyde group. Toxicological evaluation and GC/MS of impure byproduct mixtures showed that two common compounds were found in inhibiting fractions. These common compounds contained both a bay region and at least one aldehyde group.