沉积物-底栖动物体系中多壁碳纳米管对镉生态毒性的影响  

Effects of Multiwalled Carbon Nanotubes on Ecotoxicity of Cd in Sediment-Zoobenthos System

作　　者：刘珊珊[1] 龙奕[1] 王萌[1] 马陶武[1] 

机构地区：[1]吉首大学生物资源与环境科学学院,湖南吉首416000

出　　处：《生态与农村环境学报》2015年第3期414-419,共6页Journal of Ecology and Rural Environment

基　　金：国家自然科学基金(41171383)

摘　　要：人工纳米材料（ENMs）日益广泛的生产和使用将导致其大量地被释放到水环境中,ENMs 与其他污染物的相互作用可以改变污染物的生物有效性和生物毒性.分别以Cd 和底栖动物铜锈环棱螺（Bellamya aeroginosa）作为模型污染物和测试生物,采用沉积物毒性测试研究不同管径多壁碳纳米管（MWCNTs）存在条件下Cd 在铜锈环棱螺体内的生物积累变化和Cd 对肝胰脏2 种重要生物标志物超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量的影响.结果显示,不同管径MWCNTs 均能促进Cd 的生物积累,小管径（8～15 nm）MWCNTs 对Cd 生物积累的促进作用显著高于大管径（20～30 nm）MWCNTs.低Cd 浓度（5 μg·g-1）条件下,不同管径MWCNTs 处理对SOD 活性没有影响;中Cd 浓度（25 μg·g-1）条件下,不同MWCNTs 处理组SOD 活性均受显著诱导,小管径MWCNTs 处理组SOD 活性受诱导程度显著高于大管径MWCNTs 处理组;高Cd 浓度（100 μg·g-1 ）条件下,不同MWCNTs 处理组SOD 活性均受显著抑制,小管径MWCNTs 处理组的抑制程度显著高于大管径MWCNTs 处理组.中Cd 浓度条件下,MWCNTs 处理组MDA 含量比无MWCNTs 处理组显著增加;高Cd 浓度条件下,小管径MWCNTs 处理组MDA 含量显著低于无MWCNTs 处理组和大管径MWCNTs 处理组,MWCNTs 引起的高Cd 积累造成严重细胞损伤,导致MDA 含量下降.因此,在中、高Cd 浓度条件下,MWCNTs 显著增加了Cd 的生态毒性,与肝胰脏中Cd 的生物积累水平变化相吻合.MWCNTs 对不同种类污染物生态毒性的影响与MWCNTs 理化特性、环境介质和生物种类有关.The increasingly extensive production and utilization of engineered nanomaterials （ENMs） has led to release oflarge quantity of the substances into the aquatic environment, where ENMs may interact with other contaminants, and altertheir bioavailability and ecotoxicity. Heavy metal cadmium （Cd） and benthic macroinvertebrate Bellamya aeroginosa wereselected as model contaminant and test species, respectively, for an experiment to explore changes in Cd bioaccumulationand effects of Cd on two key biomarkers, superoxide dismutase （SOD） and malondialdehyde （MDA）, in the hepatopan-creas in the presence of multi-walled carbon nanotubes （MWCNTs）, different in tube diameter through sediment toxicitytest. Results show that MWCNTs, regardless of tube diameter, significantly increased Cd bioaccumulation, and MWCNTs,8-15 nm in tube diameter, displayed a greater effect promoting Cd bioaccumulation than MWCNTs, 20-30 nm in tube di-ameter. When Cd was low in concentration （5 μg·g-1）, the presence of MWCNTs did not affectcaused severe damage to cells of the zoobenthos, thus lowering drastically MDA level. Therefore, when Cd was medium orhigh in concentration, the presence of MWCNTs can significantly enhance the ecotoxicity of Cd on B. aeroginosa, whichcoincides with the change in Cd bioaccumulation in livers, and the effects of MWCNTs on ecotoxicities of various kinds ofcontaminants may potentially relate to physicochemical property of MWCNTs, environmental media, and species of the or-ganisms.

关 键 词：沉积物 底栖动物 铜锈环棱螺 Cd 多壁碳纳米管 SOD MDA 生物积累 生态毒性 

分 类 号：X171.5[环境科学与工程—环境科学]