Biophysical Environmental Chemistry Group, Department of Chemistry, University of Montreal, Montreal, QC, Canada.
Soil Chemistry and Environmental Geochemistry Group, Department of Soil, Federal University of Viçosa, Viçosa, MG, Brazil.
Environ Geochem Health. 2020 Nov;42(11):3965-3981. doi: 10.1007/s10653-020-00659-3. Epub 2020 Jul 11.
To investigate the risks posed by trace and rare earth elements (REEs) in two tropical uranium ore fields, metal concentrations from 50 vegetable samples (corn and soybean) and their corresponding agricultural soils were evaluated in a U mining area and a U-rich coal mining area in Brazil. Samples from both areas had metal concentrations (REE: La to Lu, and trace elements: As, Pb, Cd, Ni, Cu, Cr, Mn, Zn, Ba, U, Sr) that were higher than the guidelines proposed by the Brazilian environmental agency. Soils from the U mining area (Poços de Caldas) generally had higher contents of trace elements than the coal mining area (Figueira), with the exception of Ni and Cr, indicating a higher risk of pollution, which was confirmed by a pollution load index that was greater than unity. For both sites, concentrations of uranium in the soil and plants, its hazard quotients and the soil contamination factor were higher in agricultural fields closer to the mines, indicating that contamination and the consequent risks to human health were distance dependent. REE concentrations averaged 52.8 mg kg in the topsoils and 0.76 mg kg in the grains for Figueira, whereas higher values of 371 mg kg (topsoils) and 0.9 mg kg (grains) were found in Poços de Caldas. Based upon corn and soybean consumption, the estimated intake dose of the REE was lower than the intake dose predicted to be problematic for human health for both sites, indicating limited risk related to the ingestion of REE.
为了研究两种热带铀矿区痕量和稀土元素 (REE) 带来的风险，在巴西的一个铀矿区和一个富铀煤矿区，评估了 50 个蔬菜样本（玉米和大豆）及其相应农业土壤中的金属浓度。两个地区的样本都具有较高的金属浓度（REE：La 到 Lu，以及微量元素：As、Pb、Cd、Ni、Cu、Cr、Mn、Zn、Ba、U、Sr），高于巴西环境机构提出的指导值。铀矿区（波苏斯德卡尔达斯）的土壤一般比煤矿区（菲盖拉）含有更多的微量元素，除了 Ni 和 Cr，这表明污染风险更高，污染负荷指数大于 1 即可证明这一点。对于这两个地点，土壤和植物中铀的浓度、其危害系数和土壤污染因子在离矿山更近的农业用地中更高，这表明污染及其对人类健康的相应风险是与距离有关的。菲盖拉矿区表层土壤中 REE 的平均浓度为 52.8mg/kg，谷物中为 0.76mg/kg，而波苏斯德卡尔达斯矿区的表层土壤中 REE 的浓度则高达 371mg/kg，谷物中为 0.9mg/kg。基于玉米和大豆的消费，REE 的估计摄入量低于两个地区对人类健康有问题的摄入量预测，这表明与摄入 REE 相关的风险有限。
