Levels of ras oncoproteins in human plasma from 1,3-butadiene-exposed workers and controls.

In a Czech plant near Prague, 10 samples from male workers occupationally exposed to 1,3-butadiene and 13 exposed to 1,3-butadiene/styrene were compared with unexposed male negative controls, matched for age and smoking habits, for the presence of ras oncoproteins in their plasma. Proteins were separated by gel electrophoresis, transferred to a nitrocellulose membrane by Western blotting and detected by chemiluminescence, using monoclonal ras antibody as the primary antibody. There were no statistically significant differences between the 3 groups (pooled two-sample t-test, untransformed and non-parametric Mann-Whitney test). These results are in keeping with the lack of exposure-related effects for 3 cytogenetic endpoints (chromosome aberrations, sister chromatid exchanges and micronuclei) already reported (Sorsa et al., 1994 Mutation Res., 309, 321-326) for this work-force exposed to low (below 3 ppm) exposure levels.