The tobacco plant Nicotiana, has probably been responsible for more deaths than any other herb as it is market driven commodity of economic benefit. While the majority will likely be killed by use of cigarettes, tobacco use in other forms also contributes to worldwide morbidity and mortality. Chewing leaf tobacco is less used now as the ban is imposed on it. We tested the genotoxic potential of chewing leaf tobacco using in vivo cytogenetic test – peripheral blood micronucleus test. Three doses of tobacco viz., 3%, 5 %, and 10 % were given for 14 days. Cyclophosphamide, an indirect acting clastogen was used as positive control agent and it was injected intraperitoneally to the animals only once. Double distilled water was used as negative control. The frequency of MNNCE was increased in tobacco treated mice with the maximum MN being induced in NCEs at 10% dose. The parameter selected to confirm the clastogenicity of chewing leaf tobacco proved that chewing leaf tobacco at certain concentration is clastogenic.

Keywords:Chewing leaf tobacco; Peripheral blood micronucleus; Swiss albino mice; Howell–Jolly bodies.