Water Research最新文献

{"title":"Clostridium perfringens as an alternative fecal indicator bacteria in surface water quality: A national investigation in Chinese rivers","authors":"Wen Li ,&nbsp;Qingbin Yuan ,&nbsp;Xin Li ,&nbsp;Miaomiao Teng ,&nbsp;Zixuan Zhang ,&nbsp;Yi Luo ,&nbsp;Fengchang Wu","doi":"10.1016/j.watres.2025.124223","DOIUrl":"10.1016/j.watres.2025.124223","url":null,"abstract":"<div><div>Fecal indicator bacteria (FIB) are widely used to assess microbial contamination in surface water. However, traditional FIB such as fecal coliforms and enterococcus often fail to reflect pathogen-related health risks due to differences in environmental persistence and behavior. This study evaluated <em>Clostridium perfringens</em> (<em>C. perfringens</em>) as an alternative FIB through a national-scale survey of 116 sites across seven major Chinese river basins impacted by anthropogenic contamination<em>. C. perfringens</em> was detected at all sites, with a median concentration of 700 CFU/100 mL, substantially higher than fecal coliforms (26 CFU/100 mL) and enterococcus (4 CFU/100 mL). It showed stronger correlations with priority bacterial pathogens (<em>Shigella, Salmonella, Vibrio cholerae</em>) and with microbial source tracking markers of human and livestock origin. A significant wastewater treatment plant downstream decay trend (<em>k</em> = -0.21, <em>p</em> &lt; 0.05), aligned with key bacterial pathogens, further supports its diagnostic potential. Using reverse quantitative microbial risk assessment, generalized additive models, and species sensitivity distribution analysis, we derived a health-based guideline of 174 CFU/100 mL for <em>C. perfringens</em>, corresponding to the WHO benchmark of bacterial pathogens (10^–6 DALYs per person per year for drinking, swimming, and vegetable ingestion exposure). Based on this threshold, 55–100 % of sites in Chinese rivers exceeded acceptable risk levels, far surpassing exceedance rates under current fecal coliform criteria. This represents the first large-scale application of <em>C. perfringens</em> as a risk-based indicator and highlights its potential to strengthen microbial water quality monitoring and public health protection.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"286 ","pages":"Article 124223"},"PeriodicalIF":11.4,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144652258","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":"Ball-milling treated superfine powdered activated carbon triggers Mn(VII) activation for enhanced oxidation of organic contaminants","authors":"Run Huang ,&nbsp;Chaoting Guan ,&nbsp;Qin Guo ,&nbsp;Jin Jiang","doi":"10.1016/j.watres.2025.124255","DOIUrl":"10.1016/j.watres.2025.124255","url":null,"abstract":"<div><div>Carbocatalysts have been recently investigated to enhance the decontamination performance of permanganate (Mn(VII)) in water remediation. This study interestingly found that superfine powdered activated carbon (SPAC), stemming from low-cost powdered activated carbon (PAC) via ball milling, significantly enhanced Mn(VII) oxidation of trace organic contaminants (TrOCs). In contrast, PAC exhibited little effect in Mn(VII) activation. The operating parameters (i.e., time, rotational speed, and ball-to-powder mass ratio) were systematically investigated to understand the effect of ball-milling process toward the catalytic reactivity of SPAC. UV–vis spectra, methyl phenyl sulfoxide (PMSO) probe experiments, persistent free radicals (PFRs) analysis, galvanic oxidation process experiments, and electrochemical tests revealed that SPAC could activate Mn(VII) to form high-redox-potential complexes (Mn(VII)-SPAC*) rather than to produce manganese intermediates (i.e., Mn(III), MnO₂, Mn(V), and Mn(VI)), thereby facilitating the electron transfer from organics to Mn(VII). Additionally, quantitative structure-activity relationships (QSAR) between rate constants of phenol oxidation and surface characteristic descriptors of SPAC (e.g., particle average size, oxygen-containing group content, and defect degree) and density functional theory (DFT) calculations confirmed that the hydroxyl groups on SPAC were the decisive active centers for the formation of Mn(VII)-SPAC*. Overall, our discovery provides a method for designing effective carbocatalysts that leverage low-cost PAC to drive Mn(VII) activation processes.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"286 ","pages":"Article 124255"},"PeriodicalIF":11.4,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144664656","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":"CO2 drives ecological shifts through asymmetric selection in microalgae-bacteria granular for enhanced wastewater treatment and carbon fixation","authors":"Luyu Zhang ,&nbsp;Zhurui Tang ,&nbsp;Wei Zhan ,&nbsp;Beng Soon Teh ,&nbsp;Haoran Zhang ,&nbsp;Xiaowei Lv ,&nbsp;Nanqi Ren ,&nbsp;Yu Tian","doi":"10.1016/j.watres.2025.124252","DOIUrl":"10.1016/j.watres.2025.124252","url":null,"abstract":"<div><div>Microalgae-bacteria granular sludge (ABGS) systems show promising potential for simultaneous pollutant removal and CO₂ fixation in wastewater treatment, aligning with carbon neutrality goals. However, the ecological mechanisms underlying CO₂-introduced ABGS system performance adaptations remain poorly understood, hindering biosystem optimization. Here, we systematically investigated multi-level ecological adaptation mechanisms in ABGS systems under external CO₂ in low-carbon wastewater. For the first time, our study reveals that CO₂ acts as a selective force driving community evolution through asymmetric patterns: increasing phylogenetic distances among competing species while decreasing among cooperating species. This evolutionary strategy optimizes niche differentiation and functional coordination, facilitating community transition to functionally diverse Bacteroidota and Proteobacteria. Such adaptation manifests in ecological pattern shift from Zipf (55.56 % of samples) to Lognormal distribution (66.67 % of samples) reflecting enhanced resource utilization, while network reorganizes to module-hub structure, with species interactions transforming from antagonistic to synergistic relationships, improving robustness through enhanced positive species interactions. These adaptations are underpinned by coordinated molecular responses, including enrichment of carbon fixation (<em>RbcL/RbcS</em>), quorum sensing and chemotaxis pathways. Consequently, system achieved the carbon fixation of 415.52 mg/L, increased TN and COD removal by 17.64 % and 11.30 %, and increased self-aggregation potential by 13.3 % supported by elevated key metabolites. This study establishes a new framework for understanding ecological mechanisms through environmental selection, offering strategies for achieving efficient wastewater treatment and carbon neutrality goals.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"287 ","pages":"Article 124252"},"PeriodicalIF":12.4,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144664674","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":"Mitigating overload-induced stress in anaerobic digestion: long-term performance and fate of nano magnetite additives","authors":"Xiaowen Zhu ,&nbsp;Edgar Blanco ,&nbsp;Manni Bhatti ,&nbsp;Aiduan Borrion","doi":"10.1016/j.watres.2025.124241","DOIUrl":"10.1016/j.watres.2025.124241","url":null,"abstract":"<div><div>Anaerobic digestion (AD) is known as an effective sustainable waste management and energy recovery technology. However, feedstock overload disrupts microbial stability by promoting volatile fatty acid (VFA) accumulation, reactive oxygen species (ROS) generation, and foam formation, leading to reduced methane yields and potential process failure. This study investigated the long-term application of nano magnetite particles (MNPs) to mitigate overload-induced stress under semi-continuous AD operation. MNPs (20 nm and 50 nm) were applied across various dosages (10–100 mg/L) and dosing strategies. Moderate additions (10–25 mg/L) significantly improved system performance, enhancing average methane production by up to 8.6 %, reducing hydrogen content by 27 %, and lowering propionic acid concentrations by 81.2 % compared to untreated overload systems. DIET-associated genes (e.g., <em>pilA</em>) increased by 27.4–36.5 %, and the abundance of versatile methanogens (<em>Methanosarcina</em>) rose by 219.6 %. In contrast, high-dosage MNPs (100 mg/L) induced microbial stress through increased ROS, iron solubilisation, and nanoparticle aggregation (up to 60 %) under an average pH of 7.18, increasing toxicity and foaming risks. Economic analysis revealed that 25 mg/L 50 nm MNPs improved revenue ninefold and reduced slurry disposal costs by 21.3 %. However, excessive MNP accumulation highlights the need for cautious dosage control. This study demonstrates the potential of MNP application to recover overloaded AD systems and provides practical insights into long-term nanoparticle behaviour, supporting the design of resilient and sustainable AD operations. Future work should explore strategies for MNP recovery and reuse, while assess their long-term environmental fate in digestate applications.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"286 ","pages":"Article 124241"},"PeriodicalIF":11.4,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144652261","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":"A novel quad-modality deep neural network for estimating chlorophyll-a concentrations in Lianyungang’s lakes and reservoirs using Sentinel-2 MSI data","authors":"HaiHong He ,&nbsp;Xue Li ,&nbsp;Dewei Wang ,&nbsp;Wenli Qiao ,&nbsp;Yiming Sun ,&nbsp;Yu Han ,&nbsp;Feixiang Zhang ,&nbsp;Xiyu Zhao","doi":"10.1016/j.watres.2025.124246","DOIUrl":"10.1016/j.watres.2025.124246","url":null,"abstract":"<div><div>Eutrophication has become a growing threat to lake ecosystems, driven by climate change and intensified human activity. Chlorophyll-a (Chl-a), as a proxy for trophic status and algal biomass, plays a central role in water quality assessment and lake management. To estimate Chl-a concentrations, this study integrates in situ measurements with Sentinel-2 satellite imagery collected from lakes and reservoirs in Lianyungang City, China, between 2017 and 2024. Based on this dataset, we developed a novel Quad-Modality Deep Neural Network (QM-DNN) grounded in the concept of multimodal learning. The model incorporates dual-band, tri-band, and quad-band spectral features combinations, along with auxiliary temporal and environmental variables. Experimental results on the test set (<em>N</em> = 197) show that the QM-DNN model outperforms the traditional Deep Neural Network (DNN) and machine learning methods, achieving an R² of 0.73, MAE of 6.76 mg/m³, and RMSE of 12.65 mg/m³. Spatiotemporal analysis from 2017 to 2024 revealed significant variability in Chl-a concentrations. Spatially, lower concentrations were observed in the northern water bodies (mesotrophic, 6–10 mg/m³), while the central and southern regions exhibited higher levels (mildly eutrophic, 10–26 mg/m³). Temporally, mesotrophic waters increased from 7.06 % to 11.14 %, while mildly eutrophic waters slightly declined, and moderately eutrophic (26–30 mg/m³) areas remained low and stable. Correlation analysis based on ERA5 climate data identified air temperature and precipitation as key climatic drivers of Chl-a variability, both significantly positively correlated with Chl-a concentrations (<em>p</em> &lt; 0.05), whereas wind speed exhibited a weaker, site-dependent effect. To enhance model interpretability, the integrated gradients method was employed to quantify the relative contribution of each input feature. These findings highlight the effectiveness of multimodal deep learning in remote sensing-based Chl-a monitoring, providing robust support for regional water quality management and eutrophication mitigation strategies.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"286 ","pages":"Article 124246"},"PeriodicalIF":11.4,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144652259","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":"Untangling transformation products in a semi-closed sea by nontarget and suspect screening analysis","authors":"Xiaoxia Feng ,&nbsp;Haotian Wang ,&nbsp;Tingyu Li ,&nbsp;Runzeng Liu ,&nbsp;Guibin Jiang","doi":"10.1016/j.watres.2025.124247","DOIUrl":"10.1016/j.watres.2025.124247","url":null,"abstract":"<div><div>Although transformation products are important parts of chemical contaminants in the environment, their occurrence and risks remain largely unclear. In this study, MS²-initiated nontarget analysis and MS¹-initiated suspect screening analysis strategy were performed to identify transformation products. The integration of these two approaches provided a complementary strategy to broaden transformation product identification, by covering diverse structural modifications during transformation processes and fragmentation behaviors in mass spectrometry. A total of 47 transformation products originating from 29 parent compounds were identified in the Bohai Sea and the surrounding estuarine waters. The identified transformation products were widespread across the Bohai Sea, with 38 detected in over 80 % of the sites. Transformation products constituted a significant proportion of xenobiotic compounds present in the Bohai Sea, cumulatively accounting for over 50 % of the total instrumental response of their parent compounds. Transformation processes under field conditions played a key role in shaping the composition of transformation products. Moreover, transformation products was a substantial contributor to the ecological risk posed to aquatic organisms, owning to both toxicity and abundance. The results emphasize the necessity of including transformation products when profiling composition and evaluating ecological risks of xenobiotic compounds.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"286 ","pages":"Article 124247"},"PeriodicalIF":11.4,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144645365","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":"Organic ligands control microbial uptake of Hg(II): effects on Hg(II) speciation and bacterial physiology","authors":"Yuping Xiang ,&nbsp;Yueqian Chen ,&nbsp;Yingying Guo ,&nbsp;Yanwei Liu ,&nbsp;Guangliang Liu ,&nbsp;Yongguang Yin ,&nbsp;Dingyong Wang ,&nbsp;Yong Cai ,&nbsp;Guibin Jiang","doi":"10.1016/j.watres.2025.124249","DOIUrl":"10.1016/j.watres.2025.124249","url":null,"abstract":"<div><div>How organic ligands regulate microbial Hg(II) bioavailability remains a critical knowledge gap in elucidating methylmercury production and subsequent bioaccumulation in biota. Six model ligands with different functional groups (ethylenediaminetetraacetate [EDTA], citrate [CTA], cysteine [CYS], glutathione [GSH], 2, 3-dimercapto-1-propanesulfonate [DMPS], and 3-mercapto-1-propanesulfonate [MPS]) were applied to probe their impacts on Hg(II) bioavailability, by direct measurement of active cellular Hg(II) and cell physiology using a Hg(II)-specific (<em>Escherichia coli</em> PRL) and a constitutive biosensor (<em>E. coli</em> PJL), respectively. Hg(II) uptake was significantly inhibited by EDTA, CTA, DMPS, and MPS, whereas enhanced by CYS and GSH. These findings indicate co-occurred uptake mechanism other than the widely accepted membrane-ligand exchange model, since bioavailability did not inversely correlate with Hg-binding strength (CTA &lt; EDTA &lt; GSH &lt; CYS &lt; DMPS). Furthermore, ligand-induced bacterial physiological changes (e.g., thiolate inhibition vs. carboxylate neutrality) were not the primary driver of bioavailability variations. Based on Hg(II) speciation analysis and thermodynamic modelling, it was implied that sulfate reduction and CYS degradation generated sulfide corona near bacterial cells, promoting the formation of Hg sulfide nanoparticles (HgS_NP) or Hg-S clusters during Hg(II) uptake. Enhanced bioavailability of Hg(II)-CYS/GSH likely arose from passive diffusion and intracellular dissolution of these HgS species. Ambient oxygen levels further modulate Hg(II) bioavailability, with enhanced Hg(II)-CYS uptake observed under anoxic conditions, likely due to oxygen-dependent transporters expression and bacterial metabolisms. Overall, these findings highlight ligand-specific mechanisms governing Hg(II) bioavailability, emphasizing the interactions of Hg-binding strength, cell physiology, and sulfide-driven speciation in Hg biogeochemical cycling.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"286 ","pages":"Article 124249"},"PeriodicalIF":11.4,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144652262","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":"Hydrodynamic cavitation based advanced reduction process (ARP) for degradation of 2-nitrophenol in aqueous environment","authors":"Zhila Honarmandrad ,&nbsp;Kirill Fedorov ,&nbsp;Grzegorz Boczkaj","doi":"10.1016/j.watres.2025.124250","DOIUrl":"10.1016/j.watres.2025.124250","url":null,"abstract":"<div><div>Hydrodynamic cavitation (HC) along with acoustic cavitation are emerging techniques in wastewater treatment for degradation of toxic, refractory and non-biodegradable pollutants. The energy released during cavitation phenomenon has a number of applications in advanced oxidation processes (AOPs). In contrast this paper presents an effective activation of dithionite (DTN) under HC as advanced reduction process (ARP). The developed process of HC/DTN was tested for the first attempt to perform the reductive degradation of 2-nitrophenol (2-NP) in water. The complete degradation of 2-NP was achieved within 15 min at optimal conditions of C_v 0.27 with r_red 8.33, pH 11, 20 ± 2.5 °C ensuring a synergistic index (ξ) of 9.47. These results demonstrated HC as an effective tool for DTN activation. The degradation of 2-NP was primarily contributed by sulfur dioxide anion radicals (SO₂^•−) and hydrated electrons (e_aq⁻), while oxidizing radicals (i.e., HO^• and SO₄^•−) played minor role. The degradation pathway of 2-NP in HC/DTN was proposed relying on the identified intermediates using gas chromatography coupled to mass spectrometry (GC–MS). The main intermediates of 2-NP degradation were aniline and hydroquinone confirming the combined ARP/AOP action of HC/DTN. The total treatment cost of 1 m³ of contaminated water by the developed HC/DTN process was estimated as 1.08 euros according to the economic feasibility analysis. Along with rapid degradation, simple instrumentation and ultra-low costs, HC/DTN offers a promising solution for industrial water treatment.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"286 ","pages":"Article 124250"},"PeriodicalIF":11.4,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144652260","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":"Determinants of testate amoeba community dynamics in urban waters: Effects of heatwave, air pollution, and hydrological gradient","authors":"Jean Claude Ndayishimiye, Pascaline Nyirabuhoro, Cheng Xinyun, Damir Saldaev, Yuri Mazei, Xiaofei Gao","doi":"10.1016/j.watres.2025.124248","DOIUrl":"https://doi.org/10.1016/j.watres.2025.124248","url":null,"abstract":"Urban waters play a crucial role in biodiversity conservation and the provision of ecosystem services. However, the drivers of changes in these habitats remain poorly understood. This study investigates the determinants of microbial community dynamics along a 0.14 km heatwave-impacted hydrological gradient formed by three connected urban ponds in Shenzhen, southern China. The experimentation focused on extremely sensitive microorganisms, <em>testate amoebae</em>, using 30 water samples representing water columns, 30 sediment samples representing beds, and 27 microspatial factors that capture weather conditions (WC), air quality (AQ), and water quality (WQ). Both environmental conditions and testate amoeba communities varied significantly along the heatwave-impacted hydrological gradient. A total of 39 species were recorded, marking a net increase of 5 species relative to the pre-heatwave period (June–July 2020). The mean species richness was 9 ± 1 in water and 16 ± 1 in sediment. The mean absolute abundance reached 30 ± 5 ind. mL⁻¹ in water and 2,500 ± 430 ind. mL⁻¹ in sediment. Water depth and pH emerged as the most influential factors, with water depth explaining 13.4% of the total variation in testate amoeba species in water and pH accounting for 22.6% of the total variation in sediment. The variation partitioning analysis (VPA) revealed that WC, AQ, and WQ substantially influenced testate amoeba communities in sediment, accounting for 11%, 20%, and 15.5%, respectively, based on the pure percentage of community variation. Mechanistically, community changes were driven by warming-induced physiological changes, toxicity-induced stress, and hypoxia-induced stress. The neutral model explained 78.8% in water and 69.3% in sediment. Standardized effect sizes (SES) for the checkerboard score (C-score) in the null model were 0.732 (21.2%) in water and 4.437 (30.7%) in sediment, indicating that stochastic processes have a stronger influence on testate amoeba community composition than deterministic ones. These results suggest that determinants of testate amoeba community dynamics in urban waters involve both predictable factors, such as heatwaves, air pollution, and hydrological gradient (deterministic processes), and unpredictable factors, such as dispersal limitation, ecological drift, and homogenizing dispersal (stochastic processes).","PeriodicalId":443,"journal":{"name":"Water Research","volume":"678 1","pages":""},"PeriodicalIF":12.8,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144645367","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":"Exploring water affordability through subsidy policies","authors":"Thalita Salgado Fagundes ,&nbsp;Rui Cunha Marques ,&nbsp;Diogo Filipe da Cunha Ferreira ,&nbsp;Tadeu Fabricio Malheiros","doi":"10.1016/j.watres.2025.124251","DOIUrl":"10.1016/j.watres.2025.124251","url":null,"abstract":"<div><div>Access to clean water and sanitation is a fundamental human right, yet millions of people worldwide, particularly in low- and middle-income countries, face affordability barriers. This study evaluates Brazil's new social tariff policy for water supply and sanitation, enacted in 2024 through Law No 14,898, which introduces a nationally mandated social tariff, representing a rare example of nationwide affordability intervention in the sector. Using data from the Ministry of Social Development, the study examines three scenarios reflecting potential beneficiaries and their financial impacts on utilities revenue and on non-beneficiaries’ bills. Results reveal significant regional disparities in affordability and the financial strain placed on utilities, particularly in economically disadvantaged states in the north. Cross-subsidization emerges as the primary funding mechanism, yet this approach risks exacerbating affordability issues for non-beneficiary households, as observed in the study. This research underscores the critical need for affordability analyses in public policies, highlighting the importance of equitable and sustainable subsidy structures to improve water access while maintaining the financial viability of utilities.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"286 ","pages":"Article 124251"},"PeriodicalIF":11.4,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144652263","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}