Covalent DNA adducts formed in mouse epidermis by benzo(g)chrysene

The metabolic activation in mouse skin of benzo[g]chrysene (B[g]C), a moderately carcinogenic polycyclic aromatic hydrocarbon (PAH) present in coal tar, was investigated. Male Parkes mice were treated topically with 0.5 micromol B[g]C and DNA was isolated from the treated areas of skin at various times after treatment and analysed by 32P-post-labelling. Seven major adduct spots were detected, at a maximum level of 6.55 fmol adducts/microg DNA. Mouse skin treated with the PAH benzo[c]phenanthrene (B[c]Ph) gave a total of 0.24 fmol adducts/microg DNA. B[g]C-DNA adducts persisted in skin for at least 3 weeks. Treatment of mice with 0.5 micromol of the optically pure putative proximate carcinog…