摘要
为了探究"淡水贝类观察"研究体系的专用指示生物"标准化"背角无齿蚌(Anodonta woodiana)对镉(Cd^(2+))的毒性效应,研究了Cd^(2+)对钩介幼虫(<24 h,平均壳长0.25 mm)、稚蚌(<5 d,平均壳长0.27 mm)和幼蚌(6 months,平均壳长50 mm)的急性毒性,并针对Cd^(2+)积累的靶器官——鳃,分析了幼蚌脂质过氧化产物丙二醛(MDA)、成蚌(48 months,平均壳长85 mm)DNA损伤(OTM)对Cd^(2+)的响应特征。结果表明:Cd^(2+)对钩介幼虫24 h半效应浓度(EC50)为0.001 8 mg·L^(-1),对稚蚌和幼蚌96 h EC50分别为0.004 7、4.5 mg·L^(-1);Cd^(2+)浓度0.05 mg·L^(-1)和0.5 mg·L^(-1)暴露组MDA含量随时间延长呈降低的趋势,MDA含量变化与Cd^(2+)浓度之间不相关(P>0.05);OTM随暴露时间的延长呈升高的趋势,OTM变化和Cd^(2+)浓度之间表现为显著的线性正相关(P<0.05)。研究认为,钩介幼虫和稚蚌有作为Cd^(2+)的灵敏受试物种的潜力,幼蚌和成蚌适于Cd^(2+)污染的监测与评价,OTM可作为Cd^(2+)污染预警的生物标志物。
This study was undertaken to investigate the toxic effect of waterborne Cd2 +on the freshwater bivalve "standardized"Anodonta woodiana, a unique bioindicator used in the"Freshwater Mussel Watch"project. Glochidia( 24 h, mean length 0.25 mm), early juveniles( 5 days, mean length 0.27 mm), and late juveniles(6 months, mean length 50 mm)were exposed to various Cd^2+concentrations for the acute toxicity test. Furthermore, late juveniles or adults(48 months, mean length 85 mm)were used to investigate the temporal variation of lipid peroxidation[malondialdehyde(MDA)content] and DNA damage[Olive tail moment(OTM)] in gills, which are the target organs of Cd^2+accumulation. The results showed that the 24-h median effect concentration(EC50)for glochidia was 0.001 8 mg·L^-1, whereas the 96-h EC50 values for early and late juveniles were 0.004 7 mg·L^-1and 4.5 mg·L^-1, respectively. MDA content was continuously reduced over time in both the 0.05 mg·L^-1and 0.5 mg·L^-1groups, and was not related to Cd^2+concentration(P〈0.05). In contrast, the OTM values increased over time, and were linearly and positively correlated with Cd^2+concentration(P〈0.05). These results indicate that glochidia and early juveniles may be used as sensitive test organisms for Cd^2+toxicology research, late juveniles and adults may be suitable for biomonitoring Cd^2+pollution, and OTM is a valuable biomarker for early warning of Cd^2+contamination.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2017年第10期1960-1967,共8页
Journal of Agro-Environment Science
基金
国家自然科学基金青年科学基金项目(31502166)
江苏省自然科学基金项目(BK20161144)
中央级公益性科研院所基本科研业务费专项资金项目(2015JBFM13)~~