Joint Effects Of Perfluorooctane Sulphonate And ZnO Nanoparticles To Organs Of Zebrafish

For its superior surface activity, perfluorooctane sulfonate(PFOS) is widely used in textile and paper productive process. As PFOS, Nano Zinc Oxide(Nano-ZnO) has been the most important inorganic material for its excellent properties, too. Both of them are indispensible in industrial development. Many countries in the world have limited and prohibited the usage of PFOS because of its environmental persistence, biological accumulation and ecotoxicity. Meanwhile the safety problem of Nano-ZnO is now the research hotspots. Zebra fish which is internationally recognized is adopted as the testing organism of water pollution in the study. Using relevant toxicity test methods, the study researched PFOS and Nano-ZnO single pollution and combined pollution on the enzyme activity, genetoxicity and oxidative stress of Zebra fish organs. The result is expected to provide the basis of pollution detection, pollution prevention and cure of water environment.This paper summarized the development course of PFOS and Nano-ZnO, the application status of nano-materials, the development of study on the bio-safety of PFOS and Nano-ZnO, the domestic and international studies on the toxicity of persistent organic pollutants and the manufactured nanomaterials. The zebrafish were exposed to PFOS(0.2、0.4、0.8 and 1.6 mg?L-1) single solutions, Nano-ZnO(6.75、12.5、25 and 50 mg?L-1) single solutions and PFOS plus Nano-ZnO(0.2+6.75、0.4+12.5、0.8+25 and 1.6+50 mg?L-1) mixture solutions for 20 days. Activities of superoxide dismutase(SOD), catalase(CAT) and malondialdehyde(MDA) cont ents were measured in liver, gill and head of zebrafish. In addition, Caspase-3, Caspase-9 activity and Reactive oxygen species(ROS) content in liver, gill and head of zebra fish were tested in the experiment. In the SCGE(single-cell gel electrophoresis) test and micronucleus test, DNA damage of Zebra fish cells is assessed.The results demonstrated that both PFOS and Nano-ZnO single and co-exposure induced oxidative stress. In addition, PFOS plus Nano-ZnO exposure caused more serious oxidative stress than single-exposure at above exposure concentrations. The biochemical assays of liver and gill showed that, Both PFOS and Nano-ZnO single and co-exposure significantly effected the activity of SOD, CAT and the content of MDA. Besides, compare with single-exposure, the activity of CAT is significantly lower, while the content of MDA is significantly higher in co-exposure solutions. The biochemical assays of head showed that, compare with single-exposure, co-exposure had more obvious effect on the activities of SOD, CAT and the content of MDA. Under the toxicity ratio of 1:1,Nano-ZnO increased the toxicity of PFOS on oxidative stress in liver, gill and head of zebrafish at the experimental concentrations. In addition, Caspase-3, Caspase-9 activity and ROS content showed a dose-response relationship, these indexes increased with increasing PFOS and Nano-ZnO co-exposure concentrations, and significant increase were found compared to the single- exposure. The results of SCGE test and micronucleus test demonstrate that both co-exposure and single-exposure of these two kind of materials can cause significant DNA damage of zebra fish cells.