Jiang Fangyuan, Ye Cheng, Wang Feifei, Dong Tianyi, Wei Jiazhi, Kapelan Zoran, Hofman Jan, Xu Zuxin, Chu Wenhai
State Key Laboratory of Water Pollution Control and Green Resource Recycling, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Minisry of Education Key Laboratory of Yangtze River water Environment, Tongji University, shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
Bioresour Technol. 2025 Nov;435:132878. doi: 10.1016/j.biortech.2025.132878. Epub 2025 Jun 23.
The illicit connections between sewage and stormwater pipes result in the discharge of untreated sewage into receiving rivers, posing significant odor and health hazards. While thioethers are recognized as key odorants in sewage systems, their distribution in stormwater systems remain poorly characterized. This study analyzed 12 types of thioethers in stormwater pipes sampled at 21 sites in China. Advanced analytical techniques, including Mantel analysis and Structural Equation Modeling, were employed to examine the relationships between overlying water properties, sediment microbial characteristics, and thioether concentrations. Results showed that sediment thioether loads (36.77 ± 50.14 μg S/m; range: 7.24-99.96 μg S/m) were substantially higher than those in the overlying water (12.02 ± 42.52 μg S/m; range: 0.03-92.76 μg S/m), highlighting sediment as a critical pollution reservoir. Dissolved oxygen, NH-N, and terrestrial-derived dissolved organic nitrogen were identified as key factors shaping sediment microbiome composition, particularly fermentative, sulfate-reducing, and denitrifying bacteria, which in turn drives thioether formation. Specifically, dominant compounds like dimethyl disulfide and dimethyl trisulfide were found to be produced through the anaerobic fermentation of methionine and redox conversion of methanethiol, as well as the anaerobic fermentation of cysteine and methylation of polysulfides. Humic substances could facilitate methanethiol redox conversion and polysulfide methylation by serving as methyl donors and enhancing electron transfer efficiency. Additionally, NH-N may promote microbial metabolism by providing amino groups essential for the synthesis of metabolic precursors. Therefore, effective mitigation of odorous thioethers in stormwater systems necessitates integrated strategies targeting both sulfur-containing organic precursors and nitrogen-rich pollutants.
污水管道与雨水管道之间的非法连接导致未经处理的污水排入接纳河流，造成严重的气味和健康危害。虽然硫醚被认为是污水系统中的关键气味物质，但其在雨水系统中的分布情况仍知之甚少。本研究分析了在中国21个地点采集的雨水管道中的12种硫醚。采用了包括Mantel分析和结构方程模型在内的先进分析技术，以研究上覆水性质、沉积物微生物特征与硫醚浓度之间的关系。结果表明，沉积物硫醚负荷（36.77±50.14μg S/m；范围：7.24 - 99.96μg S/m）显著高于上覆水（12.02±42.52μg S/m；范围：0.03 - 92.76μg S/m），这突出了沉积物作为关键污染储库的地位。溶解氧、NH-N和陆源溶解有机氮被确定为塑造沉积物微生物群落组成的关键因素，特别是发酵菌、硫酸盐还原菌和反硝化细菌，它们进而驱动硫醚的形成。具体而言，发现二甲基二硫和二甲基三硫等主要化合物是通过蛋氨酸的厌氧发酵、甲硫醇的氧化还原转化以及半胱氨酸的厌氧发酵和多硫化物的甲基化产生的。腐殖物质可以通过作为甲基供体并提高电子转移效率来促进甲硫醇的氧化还原转化和多硫化物的甲基化。此外，NH-N可能通过提供代谢前体合成所需的氨基来促进微生物代谢。因此，有效减轻雨水系统中恶臭硫醚的排放需要针对含硫有机前体和富氮污染物的综合策略。
