Effects of Occupational Exposure with Mixture of Aromatic Organic Solvents on Liver Enzymes in Workers of an Automobile Plant

Introduction & Organic solvents have a broad range of application in industry. Hepatotoxicity of different organic halogenated solvents like carbon tetrachloride has been verified in numerous studies; however, studies investigating the association between the occupational exposure with aromatic organic solvents like benzene, toluene & xylene and hepatic toxicity are limited. The goal of this study was to review the long term effects of exposure with mixture of aromatic organic solvents, in higher amounts of permissible level, on hepatic system. This is a cross sectional study which was conducted in an automobile plant. Workers employed in the painting saloon were considered as cases and workers in assembly as controls. A questionnaire, containing demographic data like age and years of employment, was completed for each of 349 workers. After considering exclusion criteria, liver enzyme level (AST, ALT & ALP) of 163 case workers was compared with 186 controls. Concentration of mixture of organic solvents in painting saloon was twice and a half as much of the permissible level. The collected data was analyzed by the SPSS software, using T score, K2 and Linear Regression. The Mean level of ALP in case group was significantly higher than the control group (P<0.001). For AST and ALT the mean was higher in the case group but this difference was not statistically significant. Increase in ALP level had a significant association with BMI (P<0.001) and smoking (P=0.007); yet, no significant relation was seen with age and years of employment. Our study suggested that exposure with mixture of aromatic organic solvents, in higher amounts of permissible level, can cause mild functional liver damage (cholestatic type). So, it is recommended to use liver function tests, especially ALP, for screening of workers exposed to mixture of aromatic organic solvents, for preliminary detection of hepatic dysfunction.