Consiglio Nazionale delle Ricerche, Istituto di Chimica dei Composti Organometallici, via G.Moruzzi, 56124 Pisa, Italy.
Consiglio Nazionale delle Ricerche, Istituto di Chimica dei Composti Organometallici, via G.Moruzzi, 56124 Pisa, Italy.
Chemosphere. 2018 Apr;196:1-8. doi: 10.1016/j.chemosphere.2017.12.155. Epub 2017 Dec 28.
The abandoned mining area of Valdicastello Carducci (Tuscany, Italy) is characterized by the massive presence of thallium in the acid mine drainages and in the valley stream crossing the region. We previously found that Tl(III), generally considered the less stable oxidation state of thallium, is present both in the stream and in tap water distributed in the area, whereas acid mine drainages only contain Tl(I). These findings posed some concern related to the reactivity and dispersion of this toxic element in the environment. Since the valence state of thallium determines its toxicity, distribution and mobility, the study of thallium redox speciation appears crucial to understand its environmental behaviour. In this work, water samples collected from the mine drainages and the contaminated stream were adopted as model to study the distribution of aqueous Tl(I)/Tl(III) as a function of light exposure and solution properties and composition. The influence of three light sources and organic acids was evaluated. Thallium speciation was also assessed in tap water after treatment with common oxidizing agents, and in the rust crust collected from the public waterworks.
意大利托斯卡纳的瓦尔迪卡斯特罗·卡杜奇废弃矿区的酸性矿山排水和流经该地区的溪谷中，存在大量的铊。我们之前发现，Tl(III)（通常被认为是铊的较不稳定氧化态）既存在于溪流中，也存在于该地区供应的自来水中，而酸性矿山排水仅含有 Tl(I)。这些发现引起了一些关注，涉及到这种有毒元素在环境中的反应性和分散性。由于铊的价态决定了其毒性、分布和迁移性，因此研究铊的氧化还原形态对于了解其环境行为至关重要。在这项工作中，采集了矿区排水和受污染溪流的水样作为模型，以研究光照暴露和溶液特性及组成对水相中 Tl(I)/Tl(III)分布的影响。评估了三种光源和有机酸的影响。还评估了自来水在经过常见氧化剂处理后的铊形态，以及从公共供水系统收集的铁锈层中的铊形态。
