College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China.
Key Laboratory of Karst Georesources and Environment, Guizhou University, Ministry of Education, Guiyang, 550025, China.
Bull Environ Contam Toxicol. 2021 Dec;107(6):1004-1011. doi: 10.1007/s00128-021-03358-6. Epub 2021 Aug 21.
Thallium (Tl) is a highly toxic trace metal posing a significant threat to human health. Tl pollution in soils and chronic Tl poisoning related to Tl-rich sulfides weathering in the Lanmuchang mine of southwest Guizhou province, China, have been intensively studied in recent years. And yet, there are few studies on the role of secondary sulfate minerals associated with Tl mobility in this area. The sulfate minerals were characterized by XRD and SEM-EDS. The concentrations of Tl and other elements were determined by ICP-MS. The results show that sulfate minerals are predominantly melanterite, halotrichite, and fibroferrite. The average contents of Tl in rock, sulfate minerals, and soil samples were 156.4, 0.11, and 72.1 µg g, respectively. This study suggests that Tl in the mineralized rocks entered soils by pyrite oxidation with less scavenged of the sulfate minerals. The dissolution of the ferric sulfate minerals accelerates pyrite oxidation and maintains soil acidity, and this likely enhances Tl mobility from soil to crops.
铊（Tl）是一种剧毒的痕量金属，对人类健康构成重大威胁。近年来，中国贵州省西南部滥木厂矿区的土壤铊污染以及与富含铊的硫化物风化有关的慢性铊中毒受到了广泛关注。然而，关于与铊迁移相关的次生硫酸盐矿物的作用的研究却很少。采用 XRD 和 SEM-EDS 对硫酸盐矿物进行了特征描述。通过 ICP-MS 测定了 Tl 和其他元素的浓度。结果表明，硫酸盐矿物主要为铁矾、钙芒硝和纤铁矾。岩石、硫酸盐矿物和土壤样品中 Tl 的平均含量分别为 156.4、0.11 和 72.1μg/g。本研究表明，含矿岩石中的 Tl 是通过黄铁矿氧化进入土壤的，硫酸盐矿物对其的捕获较少。硫酸铁矿物的溶解加速了黄铁矿的氧化，并维持了土壤的酸度，这可能会增强 Tl 从土壤向作物的迁移能力。
