Chemistry Department (AMGC), Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic.
Chemistry Department (AMGC), Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium.
Sci Total Environ. 2022 Dec 10;851(Pt 2):157984. doi: 10.1016/j.scitotenv.2022.157984. Epub 2022 Aug 17.
The distribution and geochemistry of arsenic (As) in water and sediments of the Zenne River, a small urban river flowing through Brussels (Belgium), were assessed based on the results of 18 sampling campaigns performed between 2010 and 2021. In general, concentrations of As sharply increase between Vilvoorde and Eppegem and are up to 6-8 times higher in the section downstream of Eppegem in comparison to the upstream part of the Zenne. The monitoring surveys in which the grab water samples were taken at a 1-hour sampling frequency revealed that the large temporal variability in As concentrations found in the downstream part of the river is driven by the tidal cycle. The diffusive gradients in thin films (DGT) technique was used to assess the DGT labile As species in surface water and sediment porewater. Three DGT sorbents (Metsorb, Lewatit FO 36, and ZrO) for the determination of total As were applied to compare their performance, and the 3-mercaptopropyl-functionalized silica (3-MFS) was used for the speciation of As(III) in porewater. Arsenic species are fully labile in surface waters as the DGT time-integrated concentrations of As were in good agreement with the average concentrations calculated from the grab samplings. In sediment porewaters, As is predominantly present as non-DGT labile species (66-93 %), and the DGT labile As fraction is dominated by As(III). Flux calculations evaluating the relative importance of different As sources to the Zenne River revealed the presence of a point source on the tributary Tangebeek, which contributes to 87 % of the As load carried by the Zenne River.
基于 2010 年至 2021 年间进行的 18 次采样调查结果，评估了流经比利时布鲁塞尔的小型城市河流——泽纳河（Zenne River）中的水和沉积物中砷（As）的分布和地球化学特征。总体而言，在弗洛雷讷（Vilvoorde）和埃佩格姆（Eppegem）之间，As 的浓度急剧增加，而在埃佩格姆下游部分的浓度比泽纳河上游部分高 6-8 倍。采用 1 小时采样频率采集的Grab 水样的监测调查表明，河流下游部分发现的 As 浓度的大时间变异性是由潮汐周期驱动的。扩散梯度薄膜（DGT）技术用于评估地表水和沉积物孔隙水中的 DGT 可溶 As 物种。应用三种 DGT 吸附剂（Metsorb、Lewatit FO 36 和 ZrO）来测定总 As，以比较它们的性能，并使用 3-巯基丙基功能化硅胶（3-MFS）来对孔隙水中的 As(III)进行形态分析。As 物种在地表水中完全是可溶的，因为 DGT 时间积分的 As 浓度与从 Grab 采样计算得出的平均浓度非常吻合。在沉积物孔隙水中，As 主要以不可 DGT 溶解的物种存在（66-93%），DGT 可溶的 As 部分主要由 As(III)组成。评估不同 As 来源对泽纳河相对重要性的通量计算显示，支流坦格贝克（Tangebeek）存在一个点源，该点源贡献了泽纳河所携带的 As 负荷的 87%。
