Abstract-Our aim was to investigate the adverse effects of occupational exposure to trivalent chromium in tannery workers and unexposed persons. Trivalent chromium used in tanning industry is an environmental contaminant that acts as a carcinogen towards humans and animals. The carcinogenic potential of metals is a major issue in defining human health risk from exposure. In the present investigation, 84 tannery workers and 52 control subjects with similar mean ages, smoking prevalences and alcohol consumption were enrolled for DNA damage analysis in buccal cells by Micronucleus assay (MN). Workers showed a significant increase in micronucleated cells when compared to controls with respect to their smoking habits, alcohol consumption, age and years of exposure. The current study suggests that chronic occupational exposure to Chromium during tanning could lead to increased levels of DNA damage. The results of the present investigation are in agreement with those obtained with the same Cr (III) compounds in mutagenicity assays in bacteria and carcinogenicity tests in rodents. A re-evaluation of the mechanisms of chromium carcinogenisis is proposed.