Markers for carcinogenicity among butadiene-polymer workers in China

We examined a spectrum of genotoxic and other outcomes in 41 butadiene-poly mer production workers and 38 nonexposed controls, in China, to explore the role of butadiene in human carcinogenesis. Among butadiene-exposed workers , median air exposure was 2 ppm (6-h TWA), due largely to intermittent high -level exposures. Compared to unexposed subjects. butadiene-exposed workers had greater levels of hemoglobin N-(2,3,4-trihydroxybutyl)valine (THBVal) adducts (P<0.0001), and adduct levels tended to correlate, among butadiene- ex posed workers, with air measures (P=0.03). Butadiene-exposed workers did not differ., however, from unexposed workers with respect to frequency of uninduced or diepoxybutane-induced sister chromatid exchanges, aneuploidy a s measured by fluorescence in situ hybridization of chromosomes 1, 7, 8 and 12, glycophorin A variants or lymphocyte hprt somatic mutation. Also among the exposed, greater THBVal levels were not associated with increases in u ninduced sister chromatid exchanges, aneuploidy, glycophorin A, or hprt mut ations. Butadiene-exposed workers had greater lymphocyte (P=0.002) and plat elet counts (P=0.07) and lymphocytes as a percent of white blood cells were moderately correlated with greater THBVal levels (Spearman's <rho>=0.32, P =0.07). Among butadiene-exposed workers. several serum cytokines correlated with THBVal adduct levels. Overall, the study demonstrated exposure to but adiene in these workers, by a variety of short-term and long-term measures, but did not show specific genotoxic effects, at the chromosomal or gene le vels, related to that exposure. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.