纳米二氧化钛和铜对大型溞的联合毒性  

Joint toxicity of titanium dioxide nanoparticles and copper on Daphnia magna

作　　者：李轶[1] 殷亚远 WANG Chao 朱小山[3] 吴乾元[3] 张文龙[1] 

机构地区：[1]河海大学环境学院,江苏南京210098 [2]香港高等教育科技学院,香港特别行政区999077 [3]清华大学深圳研究生院,广东深圳518055

出　　处：《河海大学学报（自然科学版）》2016年第2期95-100,共6页Journal of Hohai University(Natural Sciences)

基　　金：国家自然科学基金(51322901;51479066);水体污染控制与治理科技重大专项(2012ZX07506-002-2)

摘　　要：为进一步研究纳米二氧化钛(nTiO_2)与铜(Cu^(2+))的相互作用和生物效应,选取大型溞(Daphnia magna)为受试生物,研究nTiO_2与Cu2+对Daphnia magna的联合毒性效应和Daphnia magna体内抗氧化系统的变化。结果表明,nTiO_2与Cu^(2+)对Daphnia magna的72 h半致死浓度(LC50)和半抑制浓度(EC50)分别为22.742 mg/L、16.739 mg/L和11.635μg/L、10.129μg/L。当nTiO_2与Cu^(2+)共存时,其联合作用的72 h-LC50和72 h-EC50分别为12.721 mg/L、8.827 mg/L和12.405μg/L、10.559μg/L。nTiO_2与Cu2+联合作用于Daphnia magna后,Daphnia magna体内超氧化物歧化酶(SOD)和还原型谷胱甘肽(GSH)活性表现为先诱导后抑制,脂质过氧化的产物丙二醛(MDA)含量逐渐升高。这表明,机体的抗氧化体系受到活性氧自由基(ROS)攻击已经崩溃,无法为Daphnia magna提供保护,氧化伤害是nTiO_2与Cu^(2+)联合毒性的关键原因。To understand the interaction of titanium dioxide nanoparticles（ nTiO2 ） and copper（ Cu2＋ ） and their biological effects, using Daphnia magna as a test animal, we studied the joint toxicity effects of nTiO2 and Cu2＋ on Daphnia magna and its internal antioxidant system. The results show that the respective values of 72 h-LC50 and 72 h-EC50 of Daphnia magna exposed to nTiO2 were 22. 742 and 16. 739 mg / L and the values of Daphnia magna exposed Cu2＋ were 11. 635 and 10. 129 μg / L. When nTiO2 and Cu2＋ coexisted, the respective values of 72 h-LC50 and 72 h-EC50 of Daphnia magna exposed to nTiO2 were 12. 721 and 8. 827mg / L and the values of Daphnia magna exposed to Cu2＋ were 12. 405 and 10. 559 μg / L. When Daphnia magna were exposed to both nTiO2 and Cu2＋, the activity of superoxide dismutase （SOD） and reduced glutathione （GSH） was first induced and then inhibited, and the malondialdehyde （MDA） content produced during lipid peroxidation increased gradually. This indicated that the antioxidant system had been attacked by reactive oxygen species （ROS）, and it could not provide protection for Daphnia magna, which was the key reason for the joint toxicity of Cu2＋ and nTiO2 .

关 键 词：纳米二氧化钛 铜 大型溞 联合毒性效应 酶活性 体内抗氧化系统 

分 类 号：X171.5[环境科学与工程—环境科学]