Urine of tobacco/areca nut chewers causes genomic damage in Chinese hamster ovary cells.

The chromosome-damaging effects of urine concentrates (UCs) from tobacco plus areca nut (T/AN) chewers (a highly popular habit and a major risk factor for oral cancer in India) were evaluated on Chinese hamster ovary (CHO) cells employing two cytogenetic end-points, namely chromosome aberration (CA) and sister chromatid exchange (SCE) frequencies. Urine creatinine levels were comparable between controls and T/AN chewers. CA and SCE frequencies in CHO cells were found to be elevated significantly (P < 0.001) following treatment with UCs prepared from T/AN chewers (UC-T/AN chewers) as well as with UCs of non-chewer controls (UC-control subjects). Moreover, elevation of these two parameters by UC-T/AN chewers was significantly higher in comparison to that of UC-controls. The results of the present study indicated that besides the oral cavity, which is a target organ for T/AN chewers, mutagens/carcinogens in tobacco and areca nut might be playing a causative role in cancer of the urinary bladder as well.