The effect of exposure to a mixture of organic solvents on liver enzymes in an auto manufacturing plant

Aim: Organic solvents are widely used in industry. Hepatotoxicity of halogenated hydrocarbons has been confirmed in many studies. However, there are few studies about the association between exposure to aromatic solvents and hepatic toxicity. The objective of this study was to assess the effects of long-term exposure to a mixture of aromatic hydrocarbons at above permissible levels on the hepatic system. Subjects and methods: In this study, two groups of workers in an auto manufacturing plant were selected, workers in the painting room as the case group and workers in the assembly room as the control group. A questionnaire including demographic data was filled out for all 349 workers. After considering inclusion and exclusion criteria, 163 and 186 workers were entered into the case and control group, respectively, and were compared for plasma levels of ALT, AST and ALP. Results: The mean plasma ALP level in the case group was significantly higher than in the control group (P < 0.001). The plasma level of ALT and AST was higher in the case group as well, but was not statistically significant. An increase in ALP had a significant association with BMI (P < 0.001) and smoking (P = 0.007). Conclusion: Results of this study show that exposure to non-permissible levels of a mixture of aromatic solvents can cause mild cholestatic hepatic dysfunction. Therefore, using liver function tests (especially ALP), which are inexpensive, simple and non-aggressive, can be recommended as a screening method for early diagnosis of hepatic dysfunction. © 2010 Springer-Verlag