Evaluation of oxidative and methylating DNA damage in painters occupationally exposed to organic solvents and paints

Introduction. Exposure to organic solvents (OS) and paints has been associated with genotoxicity and increased risk of neoplasms. However, the type of DNA damage induced for this exposure has not been yet fully characterized in humans. This knowledge would explain the mechanisms of genotoxicity caused by these compounds. Car painters in informal sector are a group highly exposed to OS and paints, due to inadequate practices of occupational safety. Objective. To identify the oxidative and methylating damage in the DNA of lymphocytes of car painters exposed to OS and paints. Materials and methods. Isolated peripheral blood lymphocytes from 62 painters and 62 unexposed subjects were analyzed by the high-throughput comet assay, coupled to the Fpg and AlkA enzymes. The categories of DNA damage evaluated were basal damage (without enzymes), oxidative and methylating damage. The parameter used to measure the damage was the percentage of DNA in tail (%TDNA). Results The %TDNA was higher in the exposed group compare to the unexposed (p < 0.05). In the exposed group, the %TDNA was higher in the oxidative damage category than the baseline (16.50 vs 12.87, p < 0.001), whereas the methylating damage did not show significant differences (14.00 vs 12.87; p > 0.05). Conclusion. In this study, exposure to OS and paints was associated with an increase in oxidative lesions in the DNA of car painters lymphocytes, such as 8oxodG and other formamidopyrimidine products, which are considered highly mutagenic.