Study Effects And Ecological Risk Assessment Of Typical Antibiotic Wastewater On Biomarkers Of Zebrafish

In the present study,We chosed streptomycin and oxytetracycline wastewater,which were two commonly-used typical antibiotics wastewater.In acute toxicity test,We preliminaried assessment the environmental safety of zebrafish.In subacute toxicity phase,we comprehensive determined the aquatic toxicity and toxic mechanism of zebrafish on two antibiotics wastewater.Including the use of detoxification enzymes,lipid Peroxidation,Antioxidant enzymes,MDA,Transaminase and Phosphorylated histone H2AX and other biochemical markers.Established the comprehensive evaluation IBR（Integrated Biom-arker Response Index）to analysis the biological toxic effects of antibiotic drugs.Then gotten the potential ecological risk levels.The results showed that:1)In 96h acute toxicity test.To oxytetracycline wastewater,zebrafish were no deaths or abnormal phenomenon.According to the US waste water toxicity benchmarks,the 96h LC₅₀>1.0TU,oxytetracycline wastewater can be determined a low toxic substance in zebrafish.Streptomycin wastewater zebrafish acute toxicity 0.3TU<96h LC₅₀<1.0TU,it is determined that streptomycin wastewater zebrafish was a chronic toxic effects.2)Exposure to subacute toxicity test in 15d.In different concentrations of oxytetra-cycline wastewater by volume.The variation of SOD activity and MDA content were same in Zebrafish muscle tissue.SOD activity of 20%and 40%concentrations re Ach Ed maximum value(195.05U·mgprot^-1,186.37U·mgprot^-1)during the experiment in 12d.Ach E inhibition-induced repeatedly showed the phenomenon,that the body has been to the outside environment change correspondingly.The change of POD activity was first rise after falling,then reaching peak at 12 days.γ-H2AX content was rising state.In different concentrations of streptomycin wastewater by volume.T-AOC and CAT were removing reactive oxygen species,the tendency were the same during the exposed,and numerical peaked at 12 days time,GSH activity changes was more complex,and the overall belongs to rise.GST activity showed a trend of twin peaks during exposure,and numerical peaked(47.23 U·mgprot^-1)at 12 days time.γ-H2AX content changed obviously in the low concentration group（7.78%,12.96%）.3)IBR showed certain regularity both concentrations and times of streptomycin and oxytetracycline in Zebrafish muscle tissue.To the oxytetracycline,IBR value and concentration were inversely related fundamental change.The longer time,the lower the level of risk.To the streptomycin,IBR value changing was more complex with exposure concentration.The IBR value changed highest of low concentrations（7.78%and 12.96%）in the first 3d.By the late gradually declined,but there were higher compared with the control group.Both wastewaters had a serious impact to aquatic organisms during exposure,early exposure changed significantly over time,gradually reduce the risk of exposure.