Longitudinal follow-up of oxidative stress and DNA damage parameters in detergent workers

BACKGROUND: The aim of this study was the follow-up of work place enzyme and detergent dust exposure effects and smoking habit on DNA damage parameters of workers and the evaluation of their antioxidant enzyme activities and lipid peroxidation with regard to bag-filter installation in the work place. MATERIAL AND METHODS: All investigated parameters were studied in a group of 153 workers of enzyme-free detergent production plant (E-free) and a group of 138 workers of enzyme-plus detergent plant (E-plus) and compared with 45 controls 7.2 years before and 3.1 years after filter system installation. The following methods were used: antioxidant enzymes by an ultraviolet–visibles spectrophotometer, malondialdehyde (MDA), 8-hydroxy-2'deoxyguanosine (8OH-2'dG) by high-performance liquid chromatography, trace elements by atomic absorption spectroscopy, and comet assay by single cell gel electrophoresis. RESULTS: Compared with controls, significant increases were observed in both detergent-exposed groups with respect to the levels of MDA, antioxidant enzyme activities, and DNA damage parameters, including 8OH-2'dG, endonuclease III-sensitive sites, and DNA strand breaks, with enhancement effect of smoking before filter system installation. After filter installation, besides significant decrease in the detergent and enzyme dust of airborne and oxidative stress indicators, there was improvement in all DNA damage investigated parameters at the end of this study. The levels of cumulative exposure index of detergent dusts decreased significantly after airborne improvement and showed positive correlation with internal biochemical parameters. CONCLUSIONS: We concluded that high levels of enzyme and detergent contents of work place dusts had a cumulative effect and smoking had a synergistic effect on the imbalance of antioxidant status and lipid peroxidation, suggesting that oxidation stress is important in the occurrence and progression of DNA damage over this study. Detergent and enzyme contents in respirable and total dust had the main role and sufficient potential in their genotoxicity.