Decreased Lung Function Associated with Occupational Exposure to Epichlorohydrin and the Modification Effects of Glutathione S-Transferase Polymorphisms

Epichlorohydrin (1-chloro-2,3,-epoxypropane; ECH) is a strong irritant of the eyes, respiratory tract, and skin. Because the toxic effect of various chemicals can be modified by metabolic traits, in this study, we also' investigated the influence of the glutathione S-transferase (GSTM1) and (GSTT1) genes on the toxic effect of ECH. In the GSTM1 null genotype workers, there is a dose-response of lung function tests (FEV₁, FEV₁/FVC, MMEF) for ECH exposure, but not in the GSTM1 non-null genotype workers. The ECH exposure was found to be significantly associated with a decreased FEV ₁ value (P = 0.09) and a decreased MMEF value (P = 0.053) after adjusting for other factors. The GSTM1 null genotype was found to be significantly associated with a decreased FEV₁ value (P = 0.038), decreased FEV₁/FVC value (P = 0.056), and decreased MMEF value (P = 0.012) after adjusting for other factors. This study indicates that obstructive lung abnormalities and small airway lung damage are associated with ECH exposure, and ECH workers with GSTM1 null-type are also associated with increased respiratory damage.