Department of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, China.
Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Department of Geotechnical Engineering, Tongji University, Shanghai, 200092, China; State Key Laboratory of Disaster Reduction in Civil Engineering, College of Civil Engineering, Tongji University, Shanghai, 200092, China.
Environ Pollut. 2024 Dec 15;363(Pt 1):125115. doi: 10.1016/j.envpol.2024.125115. Epub 2024 Oct 12.
Toxic metal content testing, environmental magnetic monitoring and in vitro bioaccessibility experiments each have their own advantages and are often used independently for environmental monitoring, but there are few studies that combine the three to evaluate the hazards of toxic metals to humans. This paper investigated the total content, magnetic properties and bioaccessibility of nine potentially toxic metal elements (Zn, Sn, Pb, Cu, Fe, Ni, Cr, Sr, Mn) in dustfall from different functional zones in Shanghai, China, and systematically compared the related results. The results show that these nine metal elements have different degrees of contamination and enrichment in outdoor dustfall, and their content distribution shows the following trend: Zn > Sn > Pb > Cu > Fe > Ni > Cr > Sr > Mn. Magnetic characteristics χ and SIRM are mostly positively correlated with the metal elements, indicating that the higher the content of magnetic minerals in the sample, the higher the concentration of metal elements. It was also found that χ, SIRM, and χ can well reflect the characteristics of dustfall pollution. The magnetic minerals have a certain degree of enrichment, and the particle size of the magnetic minerals is relatively coarse, mainly in the form of coarse multi-domain and pseudo-single-domain particles, which are largely derived from anthropogenic pollution. The χ and PM concentrations in the precipitation show relatively similar spatial trends, so χ, SIRM, and χ can be used as air pollution indices to facilitate the evaluation of metal elements pollution in dustfall. The overall trend in gastric bioaccessibility is Pb > Zn > Mn > Cu > Cr. Due to the increase in the pH of digestive fluid, the bioavailability of toxic metals decreases significantly from the gastric stage to the intestinal stage. χ, SIRM, and χ/SIRM are all related to the bioaccessibility of toxic metals in the intestinal stage, so they can be used as toxicity indicators to evaluate the bioaccessibility of toxic metals in dustfall.
有毒金属含量测试、环境磁监测和体外生物可给性实验各自具有优势，通常用于环境监测，但很少有研究将这三种方法结合起来评估有毒金属对人类的危害。本文调查了中国上海不同功能区降尘中 9 种潜在有毒金属元素（Zn、Sn、Pb、Cu、Fe、Ni、Cr、Sr、Mn）的总含量、磁性和生物可给性，并系统比较了相关结果。结果表明，这 9 种金属元素在户外降尘中存在不同程度的污染和富集，其含量分布呈现以下趋势：Zn＞Sn＞Pb＞Cu＞Fe＞Ni＞Cr＞Sr＞Mn。χ 和 SIRM 与金属元素大多呈正相关，表明样品中磁性矿物含量越高，金属元素浓度越高。还发现 χ、SIRM 和 χ 可以很好地反映降尘污染的特征。磁性矿物有一定程度的富集，磁性矿物的粒径相对较粗，主要以粗多畴和准单畴颗粒的形式存在，这在很大程度上来源于人为污染。χ 和降水 PM 浓度呈现出较为相似的空间趋势，因此 χ、SIRM 和 χ 可以作为空气污染指数，方便评估降尘中金属元素的污染情况。胃内生物可给性的整体趋势为 Pb＞Zn＞Mn＞Cu＞Cr。由于消化液 pH 值的增加，有毒金属从胃阶段到肠阶段的生物利用度显著降低。χ、SIRM 和 χ/SIRM 均与有毒金属在肠阶段的生物可给性相关，因此可以作为毒性指标来评估降尘中有毒金属的生物可给性。
