Mutagenicity and DNA damage of bisphenol A and its structural analogues in HepG2 cells.

Environmental oestrogen bisphenol A (BPA) and its analogues are widespread in our living environment. Because their production and use are increasing, exposure of humans to bisphenols is becoming a significant issue. We evaluated the mutagenic and genotoxic potential of eight BPA structural analogues (BPF, BPAF, BPZ, BPS, DMBPA, DMBPS, BP-1, and BP-2) using the Ames and comet assay, respectively. None of the tested bisphenols showed a mutagenic effect in Salmonella typhimurium strains TA98 and TA100 in either the presence or absence of external S9-mediated metabolic activation (Aroclor 1254-induced male rat liver). Potential genotoxicity of bisphenols was determined in the human hepatoma cell line (HepG2) at non-cytotoxic concentrations (0.1 μmol L(-1) to 10 μmol L(-1)) after 4-hour and 24-hour exposure. In the comet assay, BPA and its analogue BPS induced significant DNA damage only after the 24-hour exposure, while analogues DMBPS, BP-1, and BP-2 induced a transient increase in DNA strand breaks.