Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark; Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China; Sino Danish Center for Education and Research (SDC), China.
Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark; Sino Danish Center for Education and Research (SDC), China.
Sci Total Environ. 2020 May 15;717:136969. doi: 10.1016/j.scitotenv.2020.136969. Epub 2020 Jan 30.
Rare earth elements (REEs) have been increasingly diffused to the environment through mining activities and the extensive use in modern commodities, vehicular activities, coal burning and various environmental and agricultural applications. Studies of REEs in urban environments are limited with no data on REEs in urban runoff. To investigate the concentration and distribution of REEs, a total of 150 runoff samples were collected from trafficked areas, rooftops and residential parking lots in a moderate to densely populated area in Beijing, China. The runoff samples were separated into dissolved and particulate phases and analyzed by ICP-MS. The REEs were mainly (>80%) found in the runoff particulate material. The sum of REEs (ΣREE) total concentrations in urban stormwater runoff samples ranged from 0.16 to 185 μg/l. The observed mean total concentration of ΣREE in the runoff samples were 3-14 folds higher and dissolved fractions 1.5 to 6 times higher than published concentrations for recipients such as sewage channels and rivers. The distribution of REEs in runoff was dominated by light REE. Cluster analysis and Pearson's correlations revealed a strong association between the individual REEs pointing to a similar source. Higher Ce concentrations compared to other REEs indicated strong influence from traffic emission particulates. The La/Sm (5.90-8.05), La/Ce (0.53-0.58) and Ce/Yb (31.0-42.7) ratios pointed to REE sources from traffic emissions and coal burning thus defining an urban fingerprint.
稀土元素 (REEs) 通过采矿活动和现代商品、车辆活动、煤炭燃烧以及各种环境和农业应用的广泛使用，越来越多地扩散到环境中。对城市环境中 REEs 的研究有限，没有城市径流水中 REEs 的数据。为了研究 REEs 的浓度和分布，从中国北京一个中等至人口稠密地区的交通繁忙地区、屋顶和住宅停车场采集了 150 个径流样本。将径流样本分为溶解相和颗粒相，并通过 ICP-MS 进行分析。REEs 主要（>80%）存在于径流颗粒物质中。城市雨水径流水样中 ΣREE 的总浓度范围为 0.16 至 185μg/l。观察到的径流样品中 ΣREE 的总浓度平均值是污水渠和河流等受体中公布浓度的 3-14 倍，溶解部分的浓度是公布浓度的 1.5 至 6 倍。径流中 REEs 的分布以轻 REE 为主。聚类分析和 Pearson 相关分析表明，各 REEs 之间存在很强的关联，表明它们具有相似的来源。与其他 REEs 相比，Ce 浓度较高表明交通排放颗粒物的强烈影响。La/Sm（5.90-8.05）、La/Ce（0.53-0.58）和 Ce/Yb（31.0-42.7）比值表明 REEs 来自交通排放和煤炭燃烧，从而定义了城市特征。
