腐殖酸(HA)作用下纳米氧化锌对鲫鱼的毒性效应

Effect of HA on Ecotoxicity of NanoZnO in Carassius auratus

通过静态模拟实验,研究不同浓度(0、1、1.5、2.5 mg L-1)腐殖酸(Humic acid,HA)对纳米ZnO(5 mg L–1)毒性效应的影响.将鲫鱼暴露于HA与纳米ZnO混合体系中7 d后,分析Zn在鲫鱼体内的富集分布,及对鲫鱼脑部和肝脏自由基含量、抗氧化系统等的影响.结果显示:随HA浓度的增加,鲫鱼鳃部和肌肉中Zn的含量增高,眼、脑和肝部Zn含量则随之下降.纳米ZnO诱导鲫鱼肝脏和脑产生羟基自由基,HA浓度增大诱导鲫鱼肝脏和脑中SOD活性升高,MDA、GSH含量增加.纳米ZnO胁迫导致鲫鱼肝脏和脑氧化损伤,HA的浓度增加会促进纳米ZnO对鲫鱼肝脏和脑部的氧化损伤.研究表明HA改变了纳米ZnO在环境中的生物效应,因此在关注纳米材料的水生态安全时,不能忽视环境因子的影响.

To investigate the effect of humic acid （HA） with different concentrations （0, 1, 1.5 and 2.5 mg L^-1） on toxicity of ZnO nanoparticle （ZnO-NP） in the fish （Carassius auratus）, the experimental animals were exposed to HA and ZnO-NP mixtures for seven days. Then the distribution of zinc, and the changes in the ROS content and antioxidative system in the brain and liver of C. auratus were recorded. The results indicated that with the increasing of HA, the concentration of zinc increased in the gills and muscles and reduced in the eyes, brain and liver of C. auratus. Becasue ZnO-NP induced the production of OH free radicals, and the increase of HA promoted the activity of SOD in the brain and liver of C. auratus, the concentrations of MDA and GSHA increased. It was also found that the stress of ZnO-NP caused the oxidative damage of the liver and brain, which could be further induced by HA. Therefore, the results showed that HA changed biological effects of ZnO-NP, and suggested that enviornment factors could not be disregarded when considering the ecological safety of nanomaterials in the aquatic system. Fig 2, Tab 1, Ref 28