Abstract: Purpose: To detect the effects of cell proliferation inhibition and chromosome aberrations of Kuaishaling and Deltamethrin on mouse bone marrow. Methods:Two insectisides were administrated to mice at three different doses of 1 / 4, 1 / 2, 1×LD 50 (single doses of 1 / 20, 1 / 10 and 1 / 5×LD 50, the LD 50 of Kuaishaling and Deltamethrin were 72.8 mg / kg and 26 mg / kg) by gavage once a day for five days respectively, single gavaged volume was 20 ml / kg; the cell proliferation indices, the rates of chromosome structural aberrations and the rates of the cells with chromosome aberrations were detected by the methods of cytogenetics. Results: The cell proliferation indices of mouse bone marrow cells decreased significantly at all the three tested doses of these two insecticides as compared with the negative control group, the cell proliferation indices induced by Kuaishaling and Deltamethrin were 3.38±0.42～3.40±1.16 (P<0.000 01) and 5.12±0.47～5.97±0.62 (P<0.001～P<0.000 1), respectively; both the rates of chromosomal structural aberrations and the rates of the cells with chromosomal aberrations increased significantly at the high dose of Kuaishaling and the three tested doses of Deltamethrin, the rates of chromosomal structural aberrations and the rates of the cells with chromosomal aberrations induced by the high dose of Kuaishaling were 8.87±1.65(P<0.001) and 7.21±2.10(P<0.01), respectively, those induced by the three tested doses of Deltamethrin were 11.74±2.81～23.42±2.17(P<0.001～P<0.000 1) and 9.36±1.52～17.33±3.68(P<0.001～P<0.0001), respectively; the chromosomal aberration types caused by Deltamethrin were more complex than by Kuaishaling. Conclusions: Kuaishaling and Deltamethrin can not only inhibit cell proliferation, but also cause chromosome damages. Moreover, using LD 50 as the evaluating criterion, the effect of cell proliferation inhibition caused by Kuaishaling is stronger, whereas the effect of chromosome aberrations caused by Deltamethrin is stronger.

Key words: Cell proliferation index, Chromosome structural aberration, Kuaishaling, Deltamethrin