Acute Toxic Effects Of Uranium,cadmium And Copper On Fish Take The Seedlings Of Crucian Carp

With the continuous development of the world's nuclear industry,people have increased the exploitation of uranium mines.However,it has also brought a series of environmental pollution problems,especially the radioactive pollution and heavy metal pollution in the water around the uranium mines.These pollution elements include uranium,cadmium,copper,zinc,lead and so on.Radioactive pollution and heavy metal pollution in water environment not only cause huge economic losses,but also threaten the health and survival of all kinds of life in water environment,which has to arouse people's attention.In this study,the single acute toxicity and combined acute toxicity tests were carried out on three kinds of common freshwater fish seedlings with radionuclide uranium,heavy metal cadmium and copper as poisons.In the single acute toxicity test of radionuclide uranium,heavy metal cadmium and copper to crucian carp,grass carp and silver carp seedlings,the 96 h half lethal concentrations of uranium,cadmium and copper to crucian carp seedlings were 26.033 mg/L,1.174 mg/L and 0.048 mg/L,respectively;the 96 h half lethal concentrations of uranium,cadmium and copper to grass carp seedlings were 14.873 mg/L,2.549 mg/L and 0.041mg/L,respectively The half lethal concentrations of uranium,cadmium and copper were 10.403 mg/L,1.246 mg/L and 0.098 mg/L,respectively.According to the toxicity level of toxic substances to fish in China,it can be judged that the toxicity of radionuclide uranium to crucian carp,grass carp and silver carp seedlings is low;the toxicity of cadmium to crucian carp,grass carp and silver carp seedlings is toxic;the toxicity of copper to crucian carp,grass carp and silver carp seedlings is highly toxic;from the test,it can be seen that the toxicity of different poisons to the same organism and the same poison to different organisms are different There is no significant difference between the two groups.The toxicity of radionuclide uranium,heavy metal cadmium and copper to crucian carp,grass carp and silver carp seedlings was as follows: Copper > cadmium > uranium.In the joint acute toxicity test of radionuclides U,Cd and Cu on crucian carp,grass carp and silver carp seedlings,the additive index method of aquatic toxicological joint effect marking was used,and the toxicity ratio was 1:1.The results of joint toxicity test showed that: in the joint toxicity test of crucian carp and grass carp seedlings,the joint toxicity effects of U-Cd,U-Cu and U-Cd-Cu were antagonistic,while the joint toxicity effects of Cu Cd were synergistic,and the toxicity effects were not related to the ratio of poison.In the joint toxicity test of silver carp seedlings,the combined toxicity of U-Cd and U-Cu showed antagonistic effect at first,and synergistic effect at last with the extension of exposure time.The combined toxicity of copper and cadmium showed a synergistic effect,and the synergistic effect gradually increased with the extension of exposure time.The combined toxicity of U-Cd-Cu was affected by exposure time,which showed antagonistic effect at first and then synergistic effect.The toxic effect of U-Cd-Cu was not related to the ratio of toxicants,but related to exposure time and the combination of toxicants.