Association Between Genetic Polymorphisms in Styrene-Metabolizing Enzymes and Biomarkers in Styrene-Exposed Workers∗

Abstract

Single-nucleotide polymorphisms (SNP) in genes of styrene-metabolizing enzymes could modulate biomarker concentrations in blood or urine after exposure to styrene. Ten SNP were analyzed to study their influence on styrene-specific biomarkers in 89 workers of a fiber-reinforced plastic boat building factory. The internal styrene body burden was analyzed in post-shift blood and urine samples. External styrene exposure was measured by passive samplers. Spearman rank correlations between styrene exposure and biomarkers were calculated and distributions of biomarkers were checked for lognormality. Mixed linear models were applied to analyze the influence of genotypes and styrene exposure, on styrene in blood (Monday and Thursday post-shift) and on phenyglyoxylic acid (PGA; adjusted for day of measurement, Monday to Thursday) due to a lognormal distribution, smoking (current, not current), and use of respirators. Stratified analyzes for workers without and with different types of respirators were also performed. The models of both the subgroups revealed a significant influence dependent on the respirator type that workers used for inhalation protection. An influence of the external styrene concentration on the urinary PGA concentration was not observed. After implementation of the SNP into the model significant lower adjusted means of urinary PGA concentrations were found for GSTP1 105IleVal and CYP2E1 -71TT. For styrene levels in blood no significant effect was observed. A significant influence on styrene levels in blood was correlated with external styrene concentration only in workers without use of respirators. The effects of two SNP on urinary PGA decrease indicated a limited modulating SNP effect. The most effective prevention for styrene exposure was obtained with the wearing of respirators.

Polymorphism of Glutathione S-transferase Genes and the Risk of Toxic Liver Damage in Petrochemical Workers

“…They show the role of enzymes of xenobiotic metabolism in the formation of the individual sensitivity of workers in the context of hazardous industries. 19,20 In the study by Ma, et al, it was found that the Ile/Val and Val/Val genotypes are associated with a predisposition to bladder cancer caused by benzidine. 21 The results from this study indicate a selection of the homozygous Val/ Val genotype in the group of healthy workers perhaps in favor of its protectivity, confirmed by Mapp, et al, indicating the protective value of the Val/Val genotype in workers exposed to isocyanate.…”