Episodic surges in titanium dioxide engineered particle concentrations in surface waters following rainfall events
Episodic surges in titanium dioxide engineered particle concentrations in surface waters following rainfall events
复制标题
降雨事件后，地表水中二氧化钛工程颗粒浓度出现间歇性激增
DOI：
10.1016/j.chemosphere.2020.128261
复制
发表时间：
2021
期刊：
影响因子：
8.8
通讯作者：
Baalousha, Mohammed
中科院分区：
文献类型：
--
作者：
Nabi, Md Mahmudun;Wang, Jingjing;Baalousha, Mohammed
量化和表征环境系统中的工程颗粒是评估其风险的关键，但仍然具有挑战性，需要区分天然颗粒和工程颗粒。本研究的目的是表征和量化的二氧化钛工程颗粒的浓度在布罗德河，哥伦比亚，南卡罗来纳州，美国在降雨事件期间和之后。元素比分布的Ti/Nb，Ti/Fe和Ti/Al，确定在一个单一的颗粒的基础上，使用电感耦合等离子体飞行时间质谱（SP-ICP-TOF-MS），在不同的降雨事件的样品之间是相似的，表明自然发生的颗粒具有相同的元素比和起源。因此，大量水样中Ti/Nb比值的变化归因于在降雨事件期间和之后，二氧化钛工程颗粒随城市径流进入布罗德河。布罗德河中Ti、Fe、Al、Nb、Ce和La的总浓度与排放/径流量呈相同的上升和下降趋势。Ti/Nb的元素比较高（例如，330到565）比平均地壳值（例如，320)以及南卡罗来纳州哥伦比亚的地表沃茨中的自然背景元素比率（例如，266.4 ± 8.9），表明受到二氧化钛工程颗粒的污染。二氧化钛工程颗粒的浓度通过使用总钛浓度和高于天然背景比的Ti/Nb比的增加的质量平衡计算来估计。降雨事件后，布罗德河中二氧化钛工程颗粒的浓度在20至140 μg TiO 2 L − 1之间变化。二氧化钛的来源归因于城市径流，因为没有污水污染，如钆异常的小尺寸所示。本研究的结果表明，城市径流是二氧化钛工程颗粒进入城市河流的主要来源，这导致了二氧化钛工程颗粒的偶发性高浓度，这可能会在降雨过程中和降雨后造成环境风险。这项研究还强调了确定地表沃茨中工程颗粒浓度随时间变化的重要性，以便对工程颗粒进行更全面的风险评估。
Quantifying and characterizing engineered particles in environmental systems is key for assessing their risk but remains challenging and requires the distinction between natural and engineered particles. The objective of this study was to characterize and quantify the concentrations of titanium dioxide engineered particles in the Broad River, Columbia, South Carolina, United States during and following rainfall events. The elemental ratio distributions of Ti/Nb, Ti/Fe, and Ti/Al, determined on a single particle basis using inductively coupled plasma-time of flight-mass spectrometry (SP-ICP-TOF-MS), were similar between samples during the different rainfall events, indicating that naturally occurring particles had the same elemental ratios and origin. Therefore, the changes in the Ti/Nb ratios in the bulk water samples were attributed to the introduction of titanium dioxide engineered particles into the Broad River with urban runoff during and following rainfall events. The total concentrations of Ti, Fe, Al, Nb, Ce, and La in the Broad River followed the same trend of rise and fall as the discharge/runoff. The elemental ratios of Ti/Nb were higher (e.g.,330 to 565) than the average crustal values (e.g.,320) and the natural background elemental ratios in surface waters in Columbia, SC (e.g.,266.4 ± 8.9), suggesting contamination with titanium dioxide engineered particles. The concentration of titanium dioxide engineered particles were estimated by mass balance calculations using total titanium concentrations and increases in Ti/Nb ratios above the natural background ratios. The concentrations of titanium dioxide engineered particles in the Broad River varied between 20 and 140 μg TiO2L−1following rainfall events. The source of titanium dioxide was attributed to urban runoff due to the absence of sewage contamination as indicated by the low size of the gadolinium anomaly. The findings of this study demonstrate that urban runoff is a major source of titanium dioxide engineered particles to urban rivers, which results in episodic high concentrations of titanium dioxide engineered particles, which may pose environmental risks during and following rainfall events. This study also highlights the importance of determining the temporal variations in engineered particle concentrations in surface waters for a more comprehensive risk assessment of engineered particles.