Study On The Endocrine Disrupting Effects Of2,4’-DDT And Trifluralin To Zebrafish

The impacts of environmental endocrine disruptors on human and ecological environment have received worldwide attention in recent years. Compared with the advanced countries in this fidld of research specially to organochlorine, although China is still at an beginning stage. This study choosed zebrafish as the experimental animals. Refer to a short term screening test of OECD, we studied the endocrine disrupting effects of lindane and beta-endosulfan to zebrafish. The results can supplied base datas and valuable experience to the research working of envirmonmental endocrine disruptors in our country.The effects of2,4’-DDT on body length, body weight, hepaticosomatic index (HSI), gonadosomatic index (GSI), spawning and fertilization rates of zebrafish at low concentration were studied. The results showed that:after21-day exposure, the body length,body weight and GSI of zebrafish at all treated groups almost had no change when compared with the control groups. But the HIS and vitellogenin of male and female zebrafish at all treated groups of2,4’-DDT significantly increased (P<0.05).2,4’-DDT remarkably inhibited zebrafish reproductive behavior and reduced the amount of average quantities of spawning and fertilization rate of zebrafish at2μg/L and10μg/L(P<0.05). The concentration of vitellogenin in the male and female zebrafish at all treated groups significantly increased (P<0.05) afer21-day exposure.The results of SDS-PAGE and Western-blotting showed that the plasma of zebrafish contained three protein bands that reacted with mouse anti zebrafish vitellogenin monoclonal antibody.150KDa and100KDa were the major bands. Theses results demonstrated that2,4’-DDT has a certain impact on the reproduction and estrogenic impact on zebrafish at10μg/L.The effects of Trifluralin on body length, body weight, hepaticosomatic index (HSI), gonadosomatic index (GSI), hatching rates and fertilization rates of zebrafish at concentration of0.2μg/L、2μg/L、10μg/L were studied. The results showed that:the body length, body weight, GIS and HIS of male and female zebrafish at all treated groups had no significant change compared with the control groups after21-day exposure. Trifluralin inhibited zebrafish the amount of average quantities of spawning at10μg/L and fertilization rates at all concentrations had decreased remarkably(P<0.05). Although the concentration of vitellogenin in male zebrafish at all treated groups had increased significantly(P<0.05), the vitellogenin in female zebrafish had reduce by dietary concentrations used in this study.Three protein bands were proved to reacted with mouse anti zebrafish vitellogenin monoclonal antibody in the plasma of female and induced male zebrafish from the results of SDS-PAGE and Western-blotting. Theses results demonstrated that Trifluralin has reproductive toxicity and estrogenic impact on zebrafish.These results suggest that short-term exposure to2,4’-DDT and Trifluralin have endocrine disrupting effects on zebrafish.