Environmental Chemistry Department, Institute of Environmental Assessment and Water Research, IDÆA-CSIC, E-08034, Barcelona, Spain.
Departament de Química Analítica, Facultat de Química, Universitat de Barcelona, Martí i Franquès, 1-11, 08028, Barcelona, Spain.
Chemosphere. 2017 Jun;176:74-80. doi: 10.1016/j.chemosphere.2017.02.092. Epub 2017 Feb 20.
The effects of mercury (Hg) released from a chlor-alkali factory in aquatic plants along the Ebro River basin (NE Spain) were analysed considering the phytochelatins (PC) and their isoforms content in these plants. These compounds were analyzed using HPLC with amperometric detection, and the macrophytes species Ceratophyllum demersum and Myriopyllum spicatum were collected in two sampling campaigns, autumn and spring, respectively. To correlate the PC content in macrophytes with the Hg contamination, analysis of total Hg (THg) content in plants and suspended particulate matter, as well as the dissolved-bioavailable fraction of Hg in water measured by the diffusive gradient in thin film (DGT) technique were done. The results confirm the presence of PC-Ala in extracts of C. demersum and PC-desGly in M. spicatum, and the concentration of these thiol compounds depends clearly on the distance between the hot spot and the downstream sites: the higher the levels are, the closer the hot spot is. Since most of the Hg is hypothesized to be associated with SPM and transported downstream, our results of the DGT suggest that trace amounts of Hg in water can be released as free metal ions yielding a certain accumulation in plants (reaching the ppb level) that are enough for activation of induction of PCs. A few PCs species have been determined, at different seasons, indicating that they can be used as good indicators of the presence of bioavailable Hg in aquatic media throughout the year.
研究了沿埃布罗河流域（西班牙东北部）的氯碱厂释放的汞（Hg）对水生植物的影响，考虑了这些植物中植物螯合肽（PC）及其同工型的含量。使用带有安培检测的 HPLC 分析了这些化合物，分别在秋季和春季两次采样中采集了大型水生植物角果藻和水麦冬。为了将大型植物中的 PC 含量与 Hg 污染相关联，对植物和悬浮颗粒物中的总 Hg（THg）含量以及通过薄膜扩散梯度（DGT）技术测量的水中可溶解生物有效 Hg 分数进行了分析。结果证实了 C. demersum 提取物中存在 PC-Ala 和 M. spicatum 中的 PC-desGly，这些硫醇化合物的浓度明显取决于热点和下游位置之间的距离：距离越近，浓度越高。由于大部分 Hg 被假设与 SPM 相关联并向下游运输，我们的 DGT 结果表明，水中痕量 Hg 可以作为游离金属离子释放，从而在植物中产生一定的积累（达到 ppb 水平），足以激活 PC 的诱导。在不同季节确定了几种 PCs 物种，表明它们可以作为全年水生介质中生物可利用 Hg 的良好指标。
