STUDY ON THE EFFECTS OF MULTIPLE\|METALS ON Carassius auratus DNA SYNTHESIS BY USING ~3H TdR

The multiple\|metals genetoxicity on Carassius auratus was studied by using 3H TdR tracer method. The results demonstrated that the best sampling time was 6h after injection.The exposure concentration experiment showed that the multiple\|metal's toxicity to Carassius auratus was biphasic, and it would damage the DNA strange at low concentration and inhibit DNA at high concentration. It also showed that the ovum and the gill are more sensitive to multiple\|metals than other tissues, and damage concentration to them was 0 0773mg/L.Among the tissues tested the brain endured the highest concentration of multiple\|metals. There existed dose effect for both DNA repair and synthesis inhibition. The toxicity of multiple\|metal on Carassius auratus increased with exposure time. The response of Carassius auratus to multiple\|metal toxicity changed from DNA repair to DNA synthesis inhibition,the amount of 3H TdR incorporated into DNA were 50% lower than the control in the liver, gill and ovum with 72h exposure.