Study Of Triazophos Toxic Effect On Monopterus Albus

The aims of the present study were to assess the toxic effects of triazophos on the Monopterus albus. The effects of triazophos on the hatchability of embryos and the acute toxicities of triazophos on the different developmental stages of Monopterus albus, the inducing effects on micronucleated erythrocytes and the effects on blood physiological indexs of Monopterus albus, the effects on the activities of brain AChE and the effects on the liver tissue's microstructure of Monopterus albus were studied in this paper. The main results were summarized as follows:1. Resulting in the low hatchability and the later hatchability compared with control group, triazophos had great effects on the hatchability of embryos of Monopterus albus. The hatchability were reduced when triazophos concentration were increased, the regression equation of concentration-response relation in 115h was y=4.59-1.02x (x: concentration logarithm, y: probability unit of hatchability, r=0.98);2. The acute toxicities of triazophos on different development stages of Monopterus albus showed embryo was not most sensitive and the fry with average total length 1.80cm was most sensitive, the 96h LCso of embryo, fry with average total length 1.80cm and Monopterus albus with average total length 28.00cm respectively was: 1.08mg/L 0.25mg/L 0.32mg/L;3. Micronuclei test of Monopterus albus was applied to study possible mutagenic activities of triazophos. Monopterus albus were exposed to triazophos with five concentrations of 0.160 mg/L 0.107 mg/L 0.080mg/L 0.053 mg/L and 0.032mg/L for seven days. The test results indicated that triazophos could increase the frequency of micronuclei, nuclear anomalies and total nuclear anomalies erythrocytes. At certain range of triazophos concentration, the frequency of micronucleated erythrocytes showed a dosage-dependent elevation. In addition, with the increasing of the dosages, the high frequency of micronucleated erythrocytes appeared also earlier, and the high frequency of nuclear anomalies erythrocytes appeared later than the high frequency of micronucleated erythrocytes. In a word, triazophos had mutagenic actions to the erythrocytes of Monopterus albus;4. Hemoglobin and erythrocyte in the test groups were dropped, all test groups exposed for 96h and 168h compared with control group, the differences were significant at the 0.05 level (p<0.05), but there were not significant differences at the 0.05 level(p>0.05) when all test groups exposed for 24h;5. Triazophos had significant effects on the activities of brain AChE of Monopterus albus in vivo. With the concentration augmented or the time prolonged, the activities of brain AChE of Monopterus albus were dropped gradually, and the restraining degree gradually increased, the difference were significant at the 0.05 level (p<0.05) when all test groups compared with control group;6. Significant differences in the liver tissue of microstructure were found, with the concentration augmented or the time prolonged, the destroying degree of liver tissue was more significant: the boundary of cell membrane became indistinct, hepatocytes were obviously swollen, karyon were mostly pushed to one side of the cytoplasm and congestion was in the liver.