Study of the genotoxicity of the total aqueous extract of betel nut and its tannin.

Frequencies of sister-chromatid exchanges (SCEs) were measured to study the genotoxicity of the total aqueous extract of betal nut and its tannin on mouse bone-marrow cells in vivo. Betal nut aqueous extract and tannin were injected i.p. into mice at doses of 12.5, 25 or 50 micrograms/g body weight and 50, 100 or 200 micrograms/g body weight respectively for 5, 10 or 15 days. Betal nut extract induced a dose-related increase in the frequency of SCEs after five daily doses of 12.5, 25 or 50 micrograms. Significant increases in SCEs were also observed in animals dosed for 10 days with 50 micrograms/g and for 15 days with 25 or 50 micrograms/g extract. After five daily doses of 50, 100 or 200 micrograms/g of betel nut tannin there was no significant induction of SCE. Mice dosed with 200 micrograms/g tannin for 10 days, or 100 or 200 micrograms/g for 15 days, showed significant increases in the frequency of SCEs.