{"title":"A Novel Bio-LOHAS Process: Regulating DGAOs-DPAOs Interactions and Carbon Allocation through Strategic Low-DO Aeration for Low C/N Wastewater Treatment","authors":"Chuheng Xie, Zhaowei Huang, Jiale Wang, Hong Li, Runzhang Zuo, Chaoqun Leng, Zhenhao Wang, Feixiang Zan, Xiejuan Lu, Juan Mao, Xiaohui Wu, Guanghao Chen","doi":"10.1016/j.watres.2025.124323","DOIUrl":"https://doi.org/10.1016/j.watres.2025.124323","url":null,"abstract":"Conventional biological treatment of low carbon-to-nitrogen (C/N) municipal wastewater is challenged by the need for supplemental carbon sources and high aeration energy. Here, we first introduce a Biological Low Oxygen and High Activated Sludge concentration (Bio-LOHAS) system and evaluate its performance under two low- dissolved oxygen (DO) gradients strategies: a monotonically increasing DO profile (M-O) and a reverse profile (O-M). At an influent C/N ratio of 4.41 ± 0.92, the O-M strategy outperformed the M-O strategy, achieving total nitrogen (TN) and total phosphorus (TP) removal efficiency of 77.8% and 95.8%, respectively, compared with 64.3 % and 68.9 % under M-O. Integration of in-situ pathway profiling and batch experiments revealed that the O-M strategy facilitated carbon allocation and enhanced microbial synergy. Concurrently, 16S rRNA-based community analysis indicated that the O-M strategy favored the enrichment of denitrifying glycogen-accumulating organisms (DGAOs) and denitrifying phosphorus-accumulating organisms (DPAOs), thereby driving polyhydroxyalkanoates (PHAs) -mediated denitrifying phosphorus removal. Notably, it promoted a dynamic balance between DGAOs and DPAOs, optimized internal carbon source conversion efficiency, and increased microbial network complexity. Metagenomic analysis further confirmed the activation of endogenous denitrification and polyphosphate metabolic pathways, with increased abundance of key functional genes involved in PHAs-glycogen cycling and polyphosphate synthesis. More importantly, the Bio-LOHAS process reduced external carbon demand by 40% and aeration energy input by 27–33%. This study demonstrates the potential of the Bio-LOHAS process as a promising and energy-efficient strategy for low C/N municipal wastewater treatment and provides a rational basis for optimizing DO gradients in full-scale applications.","PeriodicalId":443,"journal":{"name":"Water Research","volume":"14 1","pages":""},"PeriodicalIF":12.8,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144748079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water ResearchPub Date : 2025-07-29DOI: 10.1016/j.watres.2025.124313
Cheng Ye, Fangyuan Jiang, Feifei Wang, Zoran Kapelan, Zuxin Xu, Michael R. Templeton, Wenhai Chu
{"title":"Identification, sources and accumulation behavior of priority odorants discharged to surface water from stormwater systems with illicit connections","authors":"Cheng Ye, Fangyuan Jiang, Feifei Wang, Zoran Kapelan, Zuxin Xu, Michael R. Templeton, Wenhai Chu","doi":"10.1016/j.watres.2025.124313","DOIUrl":"https://doi.org/10.1016/j.watres.2025.124313","url":null,"abstract":"The odor nuisance of urban surface water after rainfall events has aroused public concerns and threaten the aquatic organisms. Herein, the first study to investigate 150 odorants in storm sewer discharge was performed in humid regions of China. During rainfall events, the total concentrations of odorants at storm sewer outlet increased by 1.3-2.1 fold from 1.7-9.4 µg/L to 2.1-20.0 µg/L with 37 odorants having detection frequencies above 50% on rainy days, and the concentrations of total odorants in air also significantly resulting in worse odor nuisance. The accumulation of odorants in sewer sediment and the remobilization of sewer sediment were factors resulting in more intensified emission of odorants from storm sewer on rainy days. More than half of odorants discharged during rainfall were contributed by sewer sediment. Thioethers, indoles, 2-isopropyl-3-methoxy pyrazine, acetophenone and coumarin exhibited high sediment-accumulation. Quantitative structure-property relationship models revealed that enhanced sediment-accumulation of chained aliphatic and aromatic odorants can be explained by the electrostatic attraction and topological characteristic, respectively. The multicriteria analysis was further introduced for relative odorants ranking by considering the variations in hazard criteria of environmental occurrence, ecotoxicity, persistence, odor nuisance and sediment accumulation. Among priority odorants, thioethers and indoles were attributed by their distinct sediment-accumulation and odor nuisance potential, while chlorinated anisole and pinenes prioritized due to their higher ecotoxicity. These findings provide novel insights into the odorants from storm sewer discharges and explore the environmental behaviors of odorants in sewer sediment.","PeriodicalId":443,"journal":{"name":"Water Research","volume":"13 1","pages":""},"PeriodicalIF":12.8,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144737574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Chemically Recalcitrant Molecules Are the Primary Components Regulating the Electron-Donating Capacity (EDC) of Dissolved Organic Matter","authors":"Sihua Zhu, Peijie Yang, Peili Tian, Siqi Zhang, Shanyi Tian, Yongguang Yin, Jitao Lv, Caiyun Yang, Zhongbo Zhou, Zhenwu Tang, Dingyong Wang, Tao Jiang","doi":"10.1016/j.watres.2025.124316","DOIUrl":"https://doi.org/10.1016/j.watres.2025.124316","url":null,"abstract":"The electron-donating capacity (EDC) of dissolved organic matter (DOM) plays a central role in regulating environmental redox processes, and is closely governed by its chemical structure. As DOM increasingly becomes a focal point in carbon sequestration strategies aimed at mitigating climate change, understanding how its molecular characteristics influence redox functionality is critical. However, the role of DOM chemodiversity, including molecular diversity, functional diversity, and compositional traits, in governing its EDC remains underexplored at the molecular scale. In this study, representative allochthonous, autochthonous, and mixed DOM samples were analyzed using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), UV-Vis spectroscopy, and excitation-emission matrix fluorescence spectroscopy. The EDC was quantified using a decolorization assay based on ABTS reduction. Results showed that EDC was not significantly correlated with overall molecular diversity, but was strongly associated with the relative abundance of polyphenolic, highly aromatic, and unsaturated compounds. These molecules also exhibited greater persistence and formed highly interconnected and thermodynamically constrained transformation networks, indicating a structural trade-off between redox functionality and degradability. This structure–function–persistence relationship implies that changes in DOM stability during carbon sequestration may significantly influence its redox capacity, thereby modulating key environmental processes such as metal cycling, and contaminant fate. By elucidating the molecular-level linkages between DOM chemical traits and electron-donating activity, this study reveals how structural characteristics govern redox functionality, emphasizes the dominant role of composition over diversity in regulating DOM reactivity, and highlights potential ecological risks relevant to carbon stabilization strategies.","PeriodicalId":443,"journal":{"name":"Water Research","volume":"23 1","pages":""},"PeriodicalIF":12.8,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144737575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water ResearchPub Date : 2025-07-29DOI: 10.1016/j.watres.2025.124305
Luman Cheng , Zhuoan Bai , Shiru Lin , Jae-Seong Lee , Quanlong Li , Minghua Wang
{"title":"Multigenerational exposure reveals differential effects of ocean warming temporal scenarios on mercury toxicity in a marine copepod","authors":"Luman Cheng , Zhuoan Bai , Shiru Lin , Jae-Seong Lee , Quanlong Li , Minghua Wang","doi":"10.1016/j.watres.2025.124305","DOIUrl":"10.1016/j.watres.2025.124305","url":null,"abstract":"<div><div>Marine biota have been facing co-occurring stressors of ocean warming and mercury pollution for generations. However, whether and how different temporal scenarios of warming will affect mercury toxicity in organisms remain poorly understood. Here, we conducted a multigenerational experiment (F1−F5) to investigate the effects of three warming scenarios (developmental, stepwise, and future) on mercury toxicity (1 μg/L) in the marine copepod <em>Pseudodiaptomus annandalei</em>. The results showed that all three warming scenarios increased mercury accumulation in mercury-treated copepods, thereby exacerbating mercury toxicity, with the most severe toxicity response under future warming. Our phenotypic trait analysis showed that the three warming scenarios significantly decreased fecundity and grazing rate, while shortening the development time of mercury-treated <em>P. annandalei</em> compared to ambient temperature condition, ultimately compromising its population fitness. We further integrated transcriptomic and proteomic analyses for the copepods of F5. The findings indicated that the three warming scenarios decreased energy production and impaired detoxification defense, with the most pronounced molecular response occurring under future warming, providing a mechanistic understanding about increased mercury toxicity under different warming scenarios. Overall, our finding highlights the significant risk of different warming scenarios on mercury toxicity in marine copepods and provides a comprehensive understanding of multistress interaction, i.e., climate change and metal pollution, under realistic, temporally dynamic scenarios.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"287 ","pages":"Article 124305"},"PeriodicalIF":12.4,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144737572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water ResearchPub Date : 2025-07-29DOI: 10.1016/j.watres.2025.124318
Gong Chen , Xiao Qiu , Jingjing Guo , Tong Liu , Minyu Zha , Xiaowen Wu , Xing Zheng , Guo-Ping Sheng , Yunkun Wang
{"title":"Hidden risks: Unrecognized biological toxicity and antibiotic resistance spread in peracetic acid-based advanced wastewater treatment technologies","authors":"Gong Chen , Xiao Qiu , Jingjing Guo , Tong Liu , Minyu Zha , Xiaowen Wu , Xing Zheng , Guo-Ping Sheng , Yunkun Wang","doi":"10.1016/j.watres.2025.124318","DOIUrl":"10.1016/j.watres.2025.124318","url":null,"abstract":"<div><div>The escalating concern over antibiotic resistance in wastewater demands urgent attention. While advanced treatment technologies are anticipated to enhance secondary effluent quality and mitigate this issue, the associated biological toxicity and potential for resistance spread have been largely neglected. Herein, we explored the impact of peracetic acid (PAA)-based processes on antibiotic resistance during advanced secondary effluent treatment. Our findings revealed that PAA effectively inactivated most wastewater bacteria. However, it simultaneously induced environmental biotoxicity and genotoxicity, triggering a 1.5–2-fold increase in extracellular ARGs (eARGs) release and doubling horizontal gene transfer frequency. In contrast, PAA-based advanced oxidation process (PAA-AOP) demonstrated strong efficacy in detoxifying antibiotics and minimizing harm to aquatic organisms. It reduced both intracellular and extracellular ARGs by 2–4 orders of magnitude in real wastewater and significantly inhibited the conjugative transfer and transformation frequency of ARGs (by approximately 10 times), impairing their spread. Moreover, PAA-AOP reduced the abundance of pathogenic bacteria in wastewater transconjugants, thus minimizing direct harm to humans. Additionally, a membrane flow-through system designed with PAA-AOP exhibited excellent catalytic performance and stability in removing antibiotics and ARGs. These findings provide key insights into PAA-based advanced wastewater treatment, making a significant contribution to mitigating biotoxicity and antibiotic resistance in aquatic ecosystems.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"287 ","pages":"Article 124318"},"PeriodicalIF":12.4,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144719565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water ResearchPub Date : 2025-07-29DOI: 10.1016/j.watres.2025.124319
Chao Wang , Ao Xia , Dong Feng , Lei Li , Jingmiao Zhang , Yun Huang , Xianqing Zhu , Xun Zhu , Eric Trably , Qiang Liao
{"title":"Impacts of intermittent electrical stimulation on continuous electro-anaerobic digestion from wastewater: performance and multi-omics insights","authors":"Chao Wang , Ao Xia , Dong Feng , Lei Li , Jingmiao Zhang , Yun Huang , Xianqing Zhu , Xun Zhu , Eric Trably , Qiang Liao","doi":"10.1016/j.watres.2025.124319","DOIUrl":"10.1016/j.watres.2025.124319","url":null,"abstract":"<div><div>The recently reported electro-anaerobic digestion with intermittent electrical stimulation (IEAD) offers new opportunities for renewable energy storage. However, the mechanistic insights and resilience of long-term continuous and stable IEAD are still yet to be better understood. This study lasted up to 155 days of continuous operation of IEAD in up-flow anaerobic sludge blanket bioreactors to evaluate the long-term effects of different intermittent power periods on IEAD performance. The optimal electrical stimulation period was obtained for 12 h:12 h intermittence, resulting in a 15.9 % improvement of the specific methane yield while achieving an organic removal efficiency higher than 98 %. Intermittent electrical stimulation favored biofilm growth, electroactive substance secretion, and enhanced electrochemical activity and cellular repair. Genomic analysis demonstrated that IEAD microbial community was dominated by <em>Methanothrix</em>, whereas continuous energization promoted <em>Methanobacteriaceae</em> enrichment. Proteomic analysis suggested that intermittent power supply preserved functional proteins and upregulated dominant enzymes such as acetyl-CoA carboxylase biotin carboxyl carrier protein and enoyl-CoA hydratase, while conferring flexible carbon source allocation and electron transfer capacity to the suspension zone. Life cycle assessment results showed that the IEAD system could achieve an energy conversion rate of 20.6 and low carbon emissions of 7.3 g CO<sub>2-eq</sub>/MJ.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"287 ","pages":"Article 124319"},"PeriodicalIF":12.4,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144719458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water ResearchPub Date : 2025-07-29DOI: 10.1016/j.watres.2025.124320
R.M. Mwanake , G.M. Gettel , E.G. Wangari , G.W. Macharia , R. Martínez-Cuesta , S. Schulz , M. Schloter , K. Butterbach-Bahl , R. Kiese
{"title":"Elevated in-stream CO2 concentration stimulates net-N2O production from global fluvial ecosystems","authors":"R.M. Mwanake , G.M. Gettel , E.G. Wangari , G.W. Macharia , R. Martínez-Cuesta , S. Schulz , M. Schloter , K. Butterbach-Bahl , R. Kiese","doi":"10.1016/j.watres.2025.124320","DOIUrl":"10.1016/j.watres.2025.124320","url":null,"abstract":"<div><div>Riverine CO<sub>2</sub> and N<sub>2</sub>O concentrations have risen since pre-industrial times, yet their biogeochemical interactions remain unclear. This study found a positive correlation between N<sub>2</sub>O and CO<sub>2</sub> saturation in fluvial ecosystems, which was absent at high DOC:NO<sub>3</sub> ratios. Low DOC:NO<sub>3</sub> ratios and high CO<sub>2</sub> saturation promote chemoautotrophic nitrification, suggesting its key role in riverine net N<sub>2</sub>O production. In vitro experiments confirmed that elevated CO<sub>2</sub> enhances nitrification rates, nitrifier gene abundance, and N<sub>2</sub>O fluxes, indicating that the CO<sub>2</sub> fertilization effect on N<sub>2</sub>O production is a potential climate feedback. Under this effect, current global N<sub>2</sub>O emissions may be underestimated by 12 % (interquartile range: 8 – 15) due to unaccounted nocturnal CO<sub>2</sub> increases. As land use change projections suggest the conversion of natural lands into croplands and urban areas, this CO<sub>2</sub>-driven rise in riverine N<sub>2</sub>O emissions could increase, amplifying the global impacts of land use on riverine greenhouse gas emissions.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"287 ","pages":"Article 124320"},"PeriodicalIF":12.4,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144737525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Enhancing selectivity of nanofiltration membranes for mineral ions and per- and polyfluoroalkyl substances via dual-component-assisted interfacial polymerization","authors":"Chunlin Zhai , Kunpeng Zhang , Yanling Liu , Shengji Xia","doi":"10.1016/j.watres.2025.124315","DOIUrl":"10.1016/j.watres.2025.124315","url":null,"abstract":"<div><div>Highly negatively charged nanofiltration membranes with tailored pore sizes can effectively reject trace per- and polyfluoroalkyl substances (PFAS) while allowing the passage of beneficial mineral ions, making them ideal for advanced drinking water purification. This study proposed a novel dual-component-assisted interfacial polymerization (IP) strategy aiming at enhancing membrane selectivity between PFAS and mineral ions. The step-wise involvement of p-Phenylenediamine as the aqueous co-monomer and 1,3,5-triformyl phloroglucinol as the pre-loading organic phase properly tailored the IP kinetics for polyamide layer formation. This strategy achieved superior effect compared to others adopting single component or mixed organic phase, yielding high-performance membranes characterized by looser structures, higher negative charge density, thinner thickness, and enhanced hydrophilicity. The optimal membrane demonstrated a high water permeance of 20.4 L <em>m</em><sup>−2</sup> h<sup>−1</sup> bar<sup>−1</sup>, over 88 % rejections for six kinds of PFAS (300–514 Da), and a Ca<sup>2+</sup>/PFAS selectivity exceeding 37 when treating practical tap water, surpassing numerous commercial and previously developed membranes. Furthermore, the novel membrane exhibited excellent long-term stability and improved resistance to organic fouling and gypsum scaling. This study presents a promising solution of nanofiltration for drinking water treatment requiring efficient removal of trace PFAS and high preservation of mineral ions.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"287 ","pages":"Article 124315"},"PeriodicalIF":12.4,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144719460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water ResearchPub Date : 2025-07-28DOI: 10.1016/j.watres.2025.124307
Xiangyu He , Wenming Yan , Xiang Chen , Minjuan Li , Yan Wang , Zhongbo Yu
{"title":"Seasonal variation enhances dissolved arsenic dynamics in aquaculture lake at the sediment-water interface","authors":"Xiangyu He , Wenming Yan , Xiang Chen , Minjuan Li , Yan Wang , Zhongbo Yu","doi":"10.1016/j.watres.2025.124307","DOIUrl":"10.1016/j.watres.2025.124307","url":null,"abstract":"<div><div>Aquaculture promotes the accumulation of substances in sediments and alters the microenvironment state of sediment-water interfaces (SWI). However, the response mechanism of arsenic (As) dynamics in sediments to these changes remains unclear. In this study, we employed high-resolution techniques to investigate the seasonal dynamics of As at the SWI in aquaculture-impacted lake zones, systematically analyzing its mobilization pathways and associated driving mechanisms. Our findings revealed that seasonal variability significantly influenced both dissolved As concentrations in sediment porewater (ranging from 3.54 to 88.14 μg/L) and As diffusive fluxes (ranging from 1.22 to 95.58 μg·m⁻²·d⁻¹). Dissolved As were consistently higher in the aquaculture zones than non-aquaculture areas during both spring and summer. Sedimentary As fractionations differed markedly between aquaculture and non-aquaculture zones, with aquaculture sediments exhibiting higher proportions of both non-specifically adsorbed As (F1) and specifically adsorbed As (F2). Correlation analysis indicated that F1 and poorly crystalline oxyhydroxide-bound As (F3) were major contributors to As mobilization into porewater in aquaculture zones. Partial least squares path modeling revealed distinctive key mechanisms: in non-aquaculture zones, Fe/Mn (oxyhydr) oxides dominated As dissolution processes, whereas in aquaculture zones, elevated nutrient levels modified dissolved organic matter (DOM) composition, thereby altering As speciation and enhancing its dissolution. Collectively, our study advances the understanding of As biogeochemistry at the SWI in aquaculture environments and underscores the potential amplification of As mobilization due to seasonal variability, highlighting the need for continuous monitoring and management.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"287 ","pages":"Article 124307"},"PeriodicalIF":12.4,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144719566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water ResearchPub Date : 2025-07-28DOI: 10.1016/j.watres.2025.124302
Axiang Cao , Yuruo Fu , Jigang Wang , Liang Xue , Wanyang He , Qian Liu
{"title":"Impact of human activities on rare earth elements in coastal regions: Anthropogenic gadolinium sources, budget, and transport","authors":"Axiang Cao , Yuruo Fu , Jigang Wang , Liang Xue , Wanyang He , Qian Liu","doi":"10.1016/j.watres.2025.124302","DOIUrl":"10.1016/j.watres.2025.124302","url":null,"abstract":"<div><div>Rare earth elements (REEs) are emerging aquatic micropollutants, yet their anthropogenic budget and transport pathway from land sources to coastal regions remain poorly constrained. This study investigates anthropogenic impacts on REEs in Jiaozhou Bay (JZB), located on the west coast of the Yellow Sea in China, by analyzing bay water samples collected during spring 2021 (including inputs from the Dagu River and wastewater treatment plant (WWTP) effluent) and incorporating published winter 2021 bay water and groundwater data. Results revealed elevated total REE concentrations near aquaculture areas (samples collected only in spring, averaging 3578 ± 553 pmol/L), approximately fivefold higher than at other stations, likely linked to REEs-containing feeds and decomposed processes. Anthropogenic gadolinium (Gd<sub>anth</sub>) accounted for 12∼41 % of the dissolved Gd in JZB during spring, with concentrations ranging from 2.8 to 25.8 pmol/L. These concentrations were significantly higher than winter (<em>t</em>-test, <em>p</em> < 0.01), likely due to the higher Gd<sub>anth</sub> concentration in WWTP effluent during spring. Using a mass balance model, we quantitatively constrained the Gd<sub>anth</sub> budget in coastal region from various sources and sinks for the first time. Results showed that WWTP effluent was the dominant contributor to Gd<sub>anth</sub> in the bay during spring, accounting for 86 ± 18 %. Notably, WWTPs in Qingdao—the city surrounding JZB—discharged a high Gd<sub>anth</sub> flux (136.8 ± 28.4 mol/y), standing out in global rankings. The net flux of Gd<sub>anth</sub> from JZB to the North Yellow Sea is estimated at 158.3 ± 194.9 mol/y, which is comparable to the amount discharged into JZB by Qingdao's WWTPs. A two-end-member mixing model revealed that 21 ± 5 % (14∼31 %) of water masses significantly impacted by WWTP effluent in JZB were transported to the North Yellow Sea’s coastal waters. These findings underscore the urgency to enhance Gd<sub>anth</sub> monitoring and regulate WWTP discharges. This study advances the understanding of anthropogenic REE dynamics in coastal regions and provides critical insights for mitigating emerging marine pollutants.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"287 ","pages":"Article 124302"},"PeriodicalIF":12.4,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144719459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}