Ground water contamination of arsenic in drinking water is a burning problem worldwide; especially in West Bengal (India) and Bangladesh. The main endeavor in this study was to assess the role of vitamin A (2.72 microM/7 ml culture), a naturally occurring antioxidant upon arsenic-induced genotoxicity; with respect to chromosomal aberrations (structural and numerical) and micronuclei. Whole blood cultures set for 72 h were exposed to test chemicals for a period of 24 h ahead of harvesting. Arsenic concentrations tested in the present study are 0.36, 0.72 and 1.4 microM/7 ml culture. Mitomycin C (MMC), the direct acting mutagen was used as positive control. Our data indicates that at concentrations tested, arsenic-induced increase in the mean frequencies of these genotoxic indices were diminished by vitamin A, indicating its protective role towards cells from arsenic exerted injury.