[Accumulation of La(NO3)3 in mice liver and its genetic toxicity]

By using ICP-MS method, this paper determined the accumulation of La in mice liver after the mice being fed with La(NO3)3 water solution for thirty days, and through in vitro experiment, studied the effect of La(NO3)3 on the micronucleus rate of mice bone marrow cells and the cleavage action of La(NO3)3 on genome DNA to investigate the genetic toxicity of La. The results showed that when the treated concentration was 1000, 500, 300 and 50 microg x ml(-1), the amount of La in mice liver reached 1.46, 0.558, 0.529 and 0.083 microg x g(-1), respectively. Compared with control, the La amount in disposed groups' mice livers increased with increasing La(NO3)3 concentration in water (r = 0.980). T-test results showed that there existed significant differences in 1000, 500 and 300 microg x ml(-1) disposed groups when compared with the control (P < 0.05). The micronucleus rate of mice bone marrow cells increased with increasing La(NO3)3 concentration in water (r = 0.853). The in vitro experiments showed that La(NO3)3 could make DNA cleaved. It could be concluded that that La might be accumulated in organisms, and could induce the damage of genetic material in cells.