Biomonitoring of genotoxic effects among shielded manual metal arc welders.

Hexavalent chromium Cr (VI) used in shielded metal arc welding is widely recognized to act as a carcinogen, mutagen and teratogen. The carcinogenic potential of metals is a major issue in defining human health risk from exposure. Hence in the present investigation, 66 welders and 60 control subjects with similar mean ages, smoking prevalences and alcohol consumption were enrolled for DNA damage analysis of buccal cells by micronucleus (MN) and comet assay. Welders showed a significant increase in micronucleated cells compared to controls and a larger mean comet tail length. The current study thus suggested that chronic occupational exposure to Cr (VI) during welding could lead to increased level of DNA damage. Understanding the complexity of the relationships between exposure, basal DNA damage and MN frequencies requires larger scale studies and application of complementary biomarkers.