Assessing bioavailability levels of metals in effluent-affected rivers: effect of Fe(III) and chelating agents on the distribution of metal speciation.
Assessing bioavailability levels of metals in effluent-affected rivers: effect of Fe(III) and chelating agents on the distribution of metal speciation.
复制标题
评估受污水影响的河流中金属的生物利用度水平：Fe(III) 和螯合剂对金属形态分布的影响。
DOI：
10.2166/wst.2016.269
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发表时间：
2016
影响因子：
2.7
通讯作者：
S. Masunaga
中科院分区：
文献类型：
--
作者：
Shuping Han;W. Naito;S. Masunaga
为了评估Fe（III）和人为配体对Ni、Cu、Zn和Pb生物有效性的影响，采用DGT（薄膜扩散梯度）方法测量了部分城市河流中生物有效性金属的浓度，并与化学平衡模型（WHAM 7.0）计算的浓度进行了比较。假设溶解的Fe（III）（<0.45 μm膜过滤）与胶体氧化铁平衡，WHAM 7.0模型估计Ni、Cu和Zn的生物可利用浓度略高于假设不存在溶解的Fe（III）的相应估计值。相比之下，较低水平的游离铅预测WHAM 7.0模型时，溶解的Fe（III）包括在内。估计表明，大部分溶解的铅是作为胶体铁铅复合物。乙二胺四乙酸（EDTA）的浓度在采样点预测EDTA和计算的生物可利用浓度之间的关系。当胶体铁和预测的EDTA浓度都包括在WHAM 7.0计算中时，溶解的金属显示出形成EDTA络合物的强烈趋势，顺序为Ni > Cu > Zn > Pb。加入EDTA后，WHAM 7.0预测的Ni、Cu和Zn的生物可利用浓度与仅考虑腐殖物质和胶体铁的预测值不同。
To assess the effects of Fe(III) and anthropogenic ligands on the bioavailability of Ni, Cu, Zn, and Pb, concentrations of bioavailable metals were measured by the DGT (diffusive gradients in thin films) method in some urban rivers, and were compared with concentrations calculated by a chemical equilibrium model (WHAM 7.0). Assuming that dissolved Fe(III) (<0.45 μm membrane filtered) was in equilibrium with colloidal iron oxide, the WHAM 7.0 model estimated that bioavailable concentrations of Ni, Cu, and Zn were slightly higher than the corresponding values estimated assuming that dissolved Fe(III) was absent. In contrast, lower levels of free Pb were predicted by the WHAM 7.0 model when dissolved Fe(III) was included. Estimates showed that most of the dissolved Pb was present as colloidal iron-Pb complex. Ethylene-diamine-tetra-acetic acid (EDTA) concentrations at sampling sites were predicted from the relationship between EDTA and the calculated bioavailable concentration of Zn. When both colloidal iron and predicted EDTA concentrations were included in the WHAM 7.0 calculations, dissolved metals showed a strong tendency to form EDTA complexes, in the order Ni > Cu > Zn > Pb. With the inclusion of EDTA, bioavailable concentrations of Ni, Cu, and Zn predicted by WHAM 7.0 were different from those predicted considering only humic substances and colloidal iron.