title: Enhancement of benzo[a]pyrene-induced sister chromatid exchanges in lymphocytes from cigarette smokers occupationally exposed to asbestos.
abstract: The frequencies of base-line and benzo[a]pyrene [(BP) CAS 50-38-8]-induced sister chromatid exchanges (SCE) were measured in peripheral blood lymphocytes from 22 male asbestos-exposed workers and 10 nonexposed workers of comparable age. A clear association between cigarette smoking and asbestos exposure in the sensitivity of lymphocytes to BP was observed. Among asbestos-exposed workers, lymphocytes from those who smoked cigarettes were significantly more susceptible to the induction of SCE by in vitro exposure to BP (P = .01) than were lymphocytes from nonsmokers. Active smoking elevated the base-line SCE frequency in both asbestos-exposed and nonexposed workers (P = .001), and an interaction between smoking and asbestos in the production of base-line SCE was suggested (P = .07). Asbestos exposure alone was not associated with an enhanced susceptibility to the induction of SCE by BP or with an elevation of base-line SCE. Increased age was associated with an increase in SCE inducibility by BP (P = .01), and a history of smoking was marginally associated with SCE inducibility by BP (P = .07). These findings support the hypothesis that an increased susceptibility of asbestos-exposed individuals to polyaromatic hydrocarbon-induced cancer results from an enhanced sensitivity to the induction of genetic damage rather than to an asbestos-induced differential cellular metabolic capacity.
authors.forename: K T
authors.initials: KT
authors.lastname: Kelsey
authors.forename: D C
authors.initials: DC
authors.lastname: Christiani
authors.forename: J B
authors.initials: JB
authors.lastname: Little
mesh_terms: D000328:Adult; D000367:Age Factors; D001189:Aryl Hydrocarbon Hydroxylases / Q000096:biosynthesis; D001194:Asbestos / Q000009:adverse effects*; D001564:Benzo(a)pyrene / Q000633:toxicity*; D004260:DNA Repair / Q000187:drug effects; D004781:Environmental Exposure; D004790:Enzyme Induction / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D012854:Sister Chromatid Exchange / Q000187:drug effects*; D012907:Smoking
chemical_list: D001194:Asbestos; D001564:Benzo(a)pyrene; D001189:Aryl Hydrocarbon Hydroxylases