化学提取法与梯度扩散薄膜技术提取太湖沉积物中有效砷的比较  

Comparison of Sequential Chemical Extraction Procedure and DGT Technique to Measure Effective Arsenic in Sediment of Lake Taihu, China

作　　者：张茜[1] 张宇峰[1] 王晓蓉[2] 罗军 

机构地区：[1]南京工业大学环境学院,南京210009 [2]南京大学环境学院污染控制和资源化研究国家重点实验室,南京210093 [3]Lancaster Environment Centre, Lancaster University

出　　处：《农业环境科学学报》2011年第7期1398-1403,共6页Journal of Agro-Environment Science

基　　金：国家重大基础(973)研究项目:湖泊沉积物多介质迁移转化与沉积物基准(2008CB418203);欧盟科技合作专项(0911);水体污染控制与治理科技重大专项(2008ZX07316-004)

摘　　要：以底栖生物河蚬(Corbicula fluminea)为实验生物,外源三价砷污染太湖沉积物为研究对象,利用生物富集实验分别比较了DGT(Diffusive gradients in thin films)梯度扩散薄膜技术和化学连续提取法所测浓度与河蚬中砷的生物有效性的相关性,并分析了这两种方法的差异。实验结果显示随着沉积物中染毒的总砷浓度(9.48,14.12,19.88,26.86,35.66,46.42,54.25mg·kg-1)增加,DGT测得砷浓度和化学提取法所测砷含量也随之增加,Pearson相关系数均在0.98以上(P<0.01),表明这两种技术均能很好地预测沉积物中有效砷含量。通过河蚬对三价砷的暴露实验,发现当沉积物总砷含量在35.66mg·kg-1以下时,暴露14d和28d后河蚬体内富集的总砷含量与暴露浓度增加趋势一致。Pearson分析结果显示DGT法和化学提取法测得结果均与河蚬体内砷的富集量显著相关,因此这两种方法都可用于预测河蚬体内肉质部的总砷富集量。Diffusive gradients in thin films （DGT） technique and a sequential chemical extraction procedure were compared in this paper, through the bioaecumulation of clam（Corbiculafluminea） cultivated in sediment, which collected from Lake Taihu, exposed to trivalent arsenic（9.48, 14.12, 19.88, 26.86, 35.66, 46.42, 54.25 mg.kg^-1）. The effective arsenic concentration was measured by DGT and chemical extrac tion procedure. Results showed that As concentration measured by these methods had a good correlation with As contents in sediments with the high pearson correlation coefficients（0.98, P〈0.01 ）, which means these two methods can be used to predict As contents in sediments. The As contents in soft tissues of clam had the same trend with the total As in sediments when As content was below 35.66 mg·kg^-1 after exposed for 14 days and 28 days. According to pearson＇s correlation analysis, bioavailability of arsenic could be estimated by both DGT and the sequential chemical extraction procedure, suggesting that these two method can be a good tool to predict the bioaceumulation of total As in clam soft tissue.

关 键 词：梯度扩散薄膜技术 化学提取法 生物有效性 砷 河蚬 

分 类 号：X830.2[环境科学与工程—环境工程]