To assess the potential risk of mixed rare earths Changle for human embryo we used transplacental micronucleus test and single cell gel electrophoresis (SCGE) technique to detect DNA damage of embryo. The rats were administered respectively 0.3, 2, 5 and 20 mg·kg -1 mixed rare earths Changle every day orally from 6th to 18th day after pregnancy. The results show that the number of cells with micronucleus significantly increases as compared with the control except 0.3 mg·kg -1 group, which appears to be a dose effect relationship. The number of comet star cell greatly increases with increasing contamination dose as compared with the control except 0 3 mg·kg -1 group, and also displays a dose effect relationship. In conclusion, though mixed rare earth Changle is restricted by placenta membrane to enter embryo body, and more than 2 mg·kg -1 mixed rare earth Changle may cross placenta barrier and cause DNA damage of hepatocyte and developing erythrocyte of rat embryo.
展开▼