Genetic predisposition and health effect of occupational exposure to asbestos.

OBJECTIVES: As asbestos presents a direct genetic hazard for humans, a small-scale molecular epidemiological study was conducted to monitor 61 subjects long-term exposed to asbestos in comparison with 49 town controls and 21 control subjects from administration of the same factory.

RESULTS: Asbestos exposed workers had significantly higher numbers of chromosomal aberrations compared with both control groups (P=0.003). Clinical examination showed that 44.3% of exposed workers developed symptoms of asbestosis. We were interested in the relationship between the risk of asbestos-coupled diseases and individual variability in biotransformation enzymes, especially in glutathione S-transferases and microsomal epoxide hydrolase. GSTP1*105Val allele appeared less in the group of workers with asbestosis compared to those without asbestosis (18.5% vs 34.7%, P=0.044), and in subjects with developed asbestosis coupled with bronchitis compared to those without bronchitis (0% vs 25%, P=0.048). Similarly, the genotype corresponding to low activity of microsomal epoxide hydrolase was significantly decreased in workers with fibrotic plaques compared to those without plaques (26.7% vs 56.3%, P=0.045).

CONCLUSIONS: Our results suggest that GSTP1*105Val allele and low EPHX1 activity genotype may be protective for people occupationally exposed to asbestos. However, more extensive studies are needed to confirm our results.