Aim: To assess and compare the number of micronuclei in exfoliated buccal oral epithelial cells and in peripheral blood lymphocytes in habitual tobacco users. Methodology: A total of 90 participants (sample size, N=90) were drawn from the patients/ accompanying person, based on their habit history of tobacco use, who reported to the Department of Oral Medicine and Radiology. The participants were divided into 3 groups- Group 1-smokeless tobacco users (n=30), Group 2-smokers (n=30) and Group 3- individuals with no tobacco habit (n=30). Micronucleus assay was carried out in exfoliated buccal cells and in peripheral blood lymphocyte of Giemsa stained slides. A minimum of 500 cells each, from buccal mucosa and from peripheral blood lymphocytes were studied after observer blinding. Results: The results obtained indicated that smokeless tobacco users and smokers showed significant increase in micronuclei count in oral epithelium and in peripheral blood lymphocytes when compared to the controls. Conclusion: The results of this study offer convincing evidence of the genotoxic potential of tobacco (smokeless and smoked). The genotoxic chromosomal damage caused by tobacco in the epithelial cells of the buccal mucosa and in peripheral blood lymphocytes is reflected in the increased micronuclei count in smokeless tobacco users and in smokers. This may serve as a useful ‘risk assessment tool’ in individuals with tobacco habit.
