Purpose and Methods: Mutagenicity, teratogenicity and subchronic toxicity in mice or rats induced by Methylamino Abamectin(MA) were studied. Results and Conclusion: In comparison with negative control, each dosage did not show significant differences in the rates of marrow cell micronuclei and spermatic deformity of mice (P>0.05); but revealed significant difference compared to positive control (P<0.05). MA(10 500μg/plate) didn't induce positive mutations of strains TA97,TA98,TA100 and TA102 with or witho...