title: Relationships between benzo(a)pyrene-DNA adduct levels and genotoxic effects in mammalian cells.
abstract: The effectiveness of benzo(a)pyrene [B(a)P]-DNA binding as an internal dosimeter was evaluated. Data were obtained from concurrent studies, measuring B(a)P induced genotoxic effects and DNA adducts in several short-term bioassay systems: cytotoxicity, gene mutation, and sister chromatid exchange in Chinese hamster V79 cells; cytotoxicity, gene mutation, and chromosome aberrations in mouse lymphoma L5178Y TK+/-; cytotoxicity and enhanced virus transformation in Syrian hamster embryo cells; and cytotoxicity and morphological transformation in C3H10T1/2CL8 mouse embryo fibroblasts. Both total B(a)P-DNA binding and specific B(a)P-DNA adducts were measured. N2-(10 beta-[7 beta,8 alpha,9 alpha-trihydroxy-7,8,9,10-tetrahydrobenzo(a)pyrene]yl)deoxyguanosine [BPDE I-dGuo] was one of the major adducts identified in all bioassay systems. DNA binding and genotoxic responses varied significantly between bioassays. Each genetic end point was induced with a differing efficiency on a per adduct basis. However, the relationships between frequency of genetic effect or morphological transformation and B(a)P-DNA binding or BPDE I-dGuo were linear within a given assay. In order to compare biological end points of diverse frequencies in diverse biological systems, a doubling adduct level, expressed as the number of BPDE I-dGuo adducts per unit of DNA required to double the induced frequency of biological response, was applied to the data.
mesh_terms: D000818:Animals; D001564:Benzo(a)pyrene / Q000378:metabolism*; D002460:Cell Line; D002470:Cell Survival; D002471:Cell Transformation, Neoplastic / Q000187:drug effects; D002869:Chromosome Aberrations; D004247:DNA / Q000378:metabolism*; D004249:DNA Damage; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics; D007940:Leukemia L5178; D009154:Mutation; D012854:Sister Chromatid Exchange; D013329:Structure-Activity Relationship; D013937:Thymidine Kinase / Q000235:genetics
chemical_list: D001564:Benzo(a)pyrene; D004247:DNA; D007041:Hypoxanthine Phosphoribosyltransferase; D013937:Thymidine Kinase