Water Research最新文献

{"title":"Investigating spatial and temporal dynamics in microbial community composition of multiple full-scale slow sand filters in drinking water treatment","authors":"Valentina Attiani ,&nbsp;Hauke Smidt ,&nbsp;Paul W.J.J. van der Wielen","doi":"10.1016/j.watres.2025.123751","DOIUrl":"10.1016/j.watres.2025.123751","url":null,"abstract":"<div><div>Slow sand filters (SSFs) are essential for producing high-quality and sustainable drinking water, relying on chemical, physical, and microbial processes to remove nutrients, organic matter, and pathogens. Despite numerous studies on the physical and chemical mechanisms in SSFs, the microbial processes and dynamics remain poorly understood. This study bridges this knowledge gap by investigating the spatial and temporal dynamics of prokaryotic communities within SSFs, by analysing different depths and the top layer, the Schmutzdecke (SCM), over time in full-scale SSFs from different drinking water treatment plants in The Netherlands. Utilising 16S ribosomal RNA gene-targeted amplicon sequencing and quantitative PCR, we observed a horizontally uniform prokaryotic community at each depth at all analysed SSFs, suggesting effective influent water and nutrient distribution, regardless of filter size or influent inlet design. Vertically, however, the prokaryotic composition varied significantly, with the SCM showing higher biomass and diversity compared to the deeper layers. This study identified a core prokaryotic community, including the families <em>Nitrospiraceae, Pirellulaceae, Nitrosomonadaceae, Gemmataceae</em>, and <em>Vicinamibacteriaceae</em>, consistent across various depths and SSFs, and in the SCMs of different ages. Their presence suggests a central role in supporting key biological processes in SSFs such as organic matter degradation and nitrification. Additionally, the relative abundance of archaea increased with sand depth in all SSFs, suggesting their adaptation to lower-nutrient conditions found in deeper layers. Analysis of the SCM over time showed that after scraping, the prokaryotic community gradually adapted, with minimal biomass increase during the first 3.6 years, eventually evolving into a mature, diverse, and even prokaryotic community. Our findings highlight the presence of spatially distinct microbial communities at various depths of SSFs, suggesting the removal of specific compounds in distinct sand layers. Moreover, the persistence of a core prokaryotic community across different SSFs, SCM maturation stages, and even after disturbances like scraping, demonstrates that the biology in SSFs is resilient and likely ensures reliable SSF performance. It also implies possibilities for earlier SSF operational restart after cleaning than is conventionally done, but with continuous monitoring of water quality parameters to ensure microbial safety. These findings lay the groundwork for future research to focus on these microorganisms and their functional potential.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"282 ","pages":"Article 123751"},"PeriodicalIF":11.4,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143893921","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":"High absorbance of nitrate leads to surprising effects on hydroxyl radical formation during 222 nm UV treatment","authors":"Emma M. Payne, Emma G. Langelan, Karl G. Linden","doi":"10.1016/j.watres.2025.123754","DOIUrl":"https://doi.org/10.1016/j.watres.2025.123754","url":null,"abstract":"Interest in krypton chloride excimer lamps, which emit primarily at 222 nm (UV222), for applications to water treatment has been growing rapidly in the last few years, due to the greater contaminant degradation and pathogen inactivation enabled by this lower wavelength. Nitrate absorbs UV very strongly at 222 nm (ε=2747 M^-1 cm^-1) and is thus of particular interest in KrCl* water treatment. While the ability of nitrate to promote hydroxyl radical formation under UV irradiation from other UV sources has been well-demonstrated, the effect of nitrate on UV222/H₂O₂ has not been previously investigated. When nitrate is present at 5 mg-N/L or greater, addition of hydrogen peroxide, a common radical promoter in UV advanced oxidation processes, leads to a 7.3 to 20.8 % decrease in degradation of para-chlorobenzoic acid (pCBA), a probe compound for hydroxyl radical formation. This effect is attributed to 1) H₂O₂ acting solely as a scavenger, rather than source, of hydroxyl radicals due to light screening by nitrate during 222 nm UV and 2) increased formation of nitrite from nitrate photolysis when peroxide is present, leading to more hydroxyl radical scavenging. Nitrite was found to exceed the maximum contaminant level of 1 mg-N/L when nitrate was present at 7.5 mg-N/L, presenting a possible challenge for applications of UV222. However, it was also found that nitrite may act as a source of hydroxyl radicals due to its high absorbance and quantum yield at 222 nm, which can compensate for the increased hydroxyl scavenging by photo-produced nitrite. Lastly, the impact of irradiation path length, an important experimental design parameter, was investigated for the UV₂₂₂/nitrate process and found to significantly influence chemical degradation results (k_pCBA varied by 1.4-1.9 times as a function of path length), due to the high light absorption of nitrate violating several key assumptions in the standard methods for calculating UV fluence. In particular, this work challenges the inclusion of the water factor in calculating UV fluence in 222 nm studies, as the water factor corrects for photon attenuation by the background water matrix but leads to erroneous results when nitrate is present due to both nitrate's impact on the water factor by photon absorption and its role as the primary source of hydroxyl radicals during 222 nm irradiation. This work demonstrates the significant, and unexpected, impact of nitrate on UV222 advanced oxidation, identifying key issues that researchers of this technology should consider.","PeriodicalId":443,"journal":{"name":"Water Research","volume":"43 1","pages":""},"PeriodicalIF":12.8,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143894006","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 sulfur-driven denitrification pretreatment for enhancing autotrophic nitrogen removals from thiourea-containing wastewater: performance and microbial mechanisms","authors":"Jiheng Zhu ,&nbsp;Xiang Li ,&nbsp;Yayi Wang ,&nbsp;Xin Gu ,&nbsp;Han Wang ,&nbsp;Jun Ma ,&nbsp;Yong Huang","doi":"10.1016/j.watres.2025.123753","DOIUrl":"10.1016/j.watres.2025.123753","url":null,"abstract":"<div><div>Thiourea (CH₄N₂S) is a widely used industrial reagent and is frequently detected in both sewage and industrial wastewater. However, treating thiourea-containing wastewater remains challenging due to its toxicity, high ammonium concentration, and low C/N ratio. In this study, a novel integrated autotrophic-heterotrophic denitrification (IAHD)- completely autotrophic nitrogen removal over nitrite (CANON) process was developed. The degradation pathway of toxic compounds, nitrogen, and sulfur release and transformation, as well as variations in functional genes were comprehensively examined. The results show that by incorporating an IAHD unit, prior to CANON, toxic thiourea was effectively degraded by the recycled nitrate from CANON. The released sulfur and organic carbon served as electron donors facilitating efficient NO₃^--N reduction. The optimal thiourea/NO₃^--N ratio for IAHD operation was determined to be 4:1 (m:m), achieving NO₃^- and thiourea removal efficiencies of 90 % and 99 %, respectively. Additionally, NH₄⁺-N and SO₄^2--S concentrations increased by 199.9 mg/L and 201.9 mg/L, respectively. Approximately 53.3 % of thiourea was converted into high-molecular-weight biological metabolites in the IAHD unit, which were subsequently and completely degraded in the CANON unit, where a robust nitrite-shunt and anammox process occurred. 16S rRNA amplicon sequencing revealed that <em>Thiobacillus</em> (with a relative abundance of 39.9 %) was the dominant genera in the IAHD unit, followed by <em>Arenimonas</em> (10.8 %) and <em>norank_o_1013-28-CG33</em> (12.4 %), indicating that sulfur autotrophic denitrification was the primary pathway for thiourea degradation. Metagenomic analysis further confirmed that thiourea, acting as an electron donor, stimulated the expression of key functional genes involved in denitrification, sulfur oxidation, dissimilatory nitrate reduction, hydrolytic oxidation, and amino acid synthesis and transport pathways. These processes contributed to the active biological transformation of carbon, nitrogen and sulfur in the IAHD unit. This study demonstrates that implementing a prior autotrophic-heterotrophic denitrification unit effectively degrades toxic thiourea, thereby ensuring the subsequent nitrogen removal performance of CANON. This approach offers a new paradigm for the treatment of thiourea-containing wastewater, promoting a more efficient and low-carbon process.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"282 ","pages":"Article 123753"},"PeriodicalIF":11.4,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143893920","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":"PFAS Removal from Reverse Osmosis and Nanofiltration Brine by Granular Activated Carbon: Thermodynamic Insights into Salinity Effects","authors":"Jiefei Cao, Siyuan Feng, Alireza Arhami Dolatabad, Yue Zhi, Baolin Deng, Caihong Liu, Xueyan Lyu, Charlotte S.Q. Christensen, Joseph J. Pignatello, Pan Ni, Shihong Lin, Zongsu Wei, Feng Xiao","doi":"10.1016/j.watres.2025.123758","DOIUrl":"https://doi.org/10.1016/j.watres.2025.123758","url":null,"abstract":"We explored an underexplored area in water treatment by examining the removal of per- and polyfluoroalkyl substances (PFAS) from reverse osmosis/nanofiltration (RO/NF) brine. We first compared multiple RO/NF membranes, revealing that DK and NF270 showed sub-optimal removal (&lt;90%) of C4−C8 PFAS, SW30 had low flux (&lt;15 L/m²/h at 8 bar), and NFX exhibited significant adsorption of perfluorosulfonic acids (e.g., 8 µmol/m²). To address the PFAS-enriched brine generated from membrane treatment, we further evaluated activated carbon (GAC) and anion-exchange (AIX) resin, both of which efficiently removed moderate- and long-chain PFAS from brine. Although AIX outperformed GAC, the ion exchange contribution was small for short-chain PFAS like perfluorobutanoic acid (PFBA, C4) but increased with chain length, driven by the hydrophobic effect facilitating the migration to near-surface regions of resins. Equilibrium batch experiments and thermodynamic modeling revealed a disproportionate salinity impact on PFAS adsorption by GAC, with short-chain PFAS (e.g., PFBA) experiencing more pronounced adsorption reduction than longer-chained homologs as NaCl concentrations increased. This reduction was driven by a significant change in a free energy component unrelated to the hydrophobic or electrostatic interactions, likely due to the competitive adsorption of Cl⁻ ions and short-chain PFAS anions or the formation of hydration shells around Na⁺ and Cl⁻ ions, obstructing the pathways for weakly hydrophobic PFAS (e.g., PFBA) within the GAC pore network. The salting-out effect was found to be unimportant. This study provides new insights into salinity-dependent sorptive removal of PFAS from high-ionic-strength water such as RO/NF brine.","PeriodicalId":443,"journal":{"name":"Water Research","volume":"43 1","pages":""},"PeriodicalIF":12.8,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143893922","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":"Genetic, metabolic and toxicological diversity within Prymnesium parvum (Haptophyte) from Polish waterbodies","authors":"Hanna Mazur-Marzec ,&nbsp;Michał Grabski ,&nbsp;Robert Konkel ,&nbsp;Marta Cegłowska ,&nbsp;Zuzanna Cyske ,&nbsp;Lidia Gaffke ,&nbsp;Łukasz Grabowski ,&nbsp;Anastasia Hiskia ,&nbsp;Marek Kajs ,&nbsp;Triantafyllos Kaloudis ,&nbsp;Agnieszka Napiórkowska-Krzebietke ,&nbsp;Karolina Pierzynowska ,&nbsp;Estera Rintz ,&nbsp;Sofia Iliakopoulou ,&nbsp;Semko Walat ,&nbsp;Sevasti-Kiriaki Zervou ,&nbsp;Monika Zielenkiewicz ,&nbsp;Grzegorz Węgrzyn","doi":"10.1016/j.watres.2025.123744","DOIUrl":"10.1016/j.watres.2025.123744","url":null,"abstract":"<div><div>Toxic blooms of <em>Prymnesium parvum</em> pose one of the most serious environmental threats. This alga occurs worldwide and has devastating effects on gill-breathing organisms inhabiting inland waters. In 2022, Polish society was faced with the problem for the first time. A high biomass of <em>P. parvum</em> in the Gliwice Canal, the Odra River and the oxbow lakes resulted in large-scale fish kills and significant economic losses. Since then, the toxic alga has become a permanent component of the Gliwice Canal phytoplankton community. Studies on <em>P. parvum</em> from other geographical regions have revealed existence of genotypic and phenotypic variation between and within the populations. Therefore, it was important to examine the specific characteristics of <em>P. parvum</em> from Polish water bodies. Here, we present the results of studies on the dynamics of B-type prymnesins (PRMs) production by <em>P. parvum</em> in the Gliwice Canal in 2023. For the purpose of the study, three B-type PRM variants were isolated and used as standards for toxins quantification and toxicity assessment. Differences in cytotoxicity of three isolated B-type prymnesins against fish (RTgill-W1) and human cells (fibroblasts – HDFa and lung cancer cells – A549) were documented for the first time. The lack of a clear correlation between the number of <em>P. parvum</em> cells and PRMs concentration indicates the heterogeneity of the population. Molecular characterisation of <em>P. parvum</em> CCNP2001 strain from Polish waters was also performed. The genome of the strain was sequenced, and the organisation of the <em>PKZILLA</em> genes involved in the biosynthesis of PRMs was described. These genes were present in all analysed bloom samples and in the isolated <em>P. parvum</em> strain. Analysis of the 5.8S rRNA gene sequence yielded unexpected results which indicated that CCNP2001 belongs to a type A prymnesin-producing strain. Additionally, high-resolution mass spectrometry analyses revealed the presence of A-type prymnesin in CCNP2001, supporting the findings of the genetic studies. This study also represents the first investigation into the impact of environmental conditions on the expression of the <em>PKZILLA-1</em> and <em>PKZILLA-2</em> genes in <em>P. parvum.</em> The obtained results were compared to prymnesin production level. Our broad-scale studies provided new data on the dynamics, toxicity of PRMs, and molecular characteristics of <em>P. parvum</em> from Polish waterbodies. The results also highlighted existing gaps in knowledge regarding population diversity, the role of prymnesins, and potentially other metabolites, in harmful effects of <em>P. parvum</em> blooms.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"282 ","pages":"Article 123744"},"PeriodicalIF":11.4,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143889916","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":"Data assimilation for prediction of ammonium in wastewater treatment plant: From physical to data driven models","authors":"Victor Bertret ,&nbsp;Roman Le Goff Latimier ,&nbsp;Valérie Monbet","doi":"10.1016/j.watres.2025.123673","DOIUrl":"10.1016/j.watres.2025.123673","url":null,"abstract":"<div><div>This study compares various modeling approaches to predict ammonium concentration in wastewater treatment plants (WWTPs), with a focus on integrating data assimilation techniques. It explores white-box, grey-box, and black-box models, evaluating their ability to capture the complex dynamics of WWTPs and manage uncertainties associated with limited data and sensor noise. The article highlights the importance of data assimilation for simultaneously calibrating model parameters, latent variables (such as unmeasured species concentrations), and quantifying prediction uncertainty. Simulation results demonstrate that the non-parametric black box model outperforms all other models in terms of predictive accuracy and uncertainty estimation. This finding underscores the effectiveness of machine learning when integrated with data assimilation techniques to extract insights from training datasets, even in the presence of limited data. Interestingly, the addition of an extra sensor, such as an oxygen sensor, did not enhance model performance. Experiments conducted in a real system showed that the non-parametric black box model could effectively capture the general dynamics of ammonium concentration in an actual wastewater treatment plant. However, its performance was somewhat diminished compared to simulation results, likely due to variability in input concentrations that were not accounted for in the model.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"282 ","pages":"Article 123673"},"PeriodicalIF":11.4,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143885333","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 sewer low-loss transportation by food waste microencapsulation treatment: Dual suppression of organic leaching and biofilm architecture-function for mitigating hazardous gases and blockage risks","authors":"Zigeng Zhang ,&nbsp;Bo Liu ,&nbsp;Wentao Chen ,&nbsp;Duoduo Liu ,&nbsp;Linjun Li ,&nbsp;Yujie Ren ,&nbsp;Wenjie Wang ,&nbsp;Honglin Yuan ,&nbsp;Heliang Pang ,&nbsp;Zhiqiang Zhang ,&nbsp;Bangyou Liao ,&nbsp;Jinsuo Lu","doi":"10.1016/j.watres.2025.123749","DOIUrl":"10.1016/j.watres.2025.123749","url":null,"abstract":"<div><div>Food waste management posed a critical global sustainability challenge, with significant environmental, economic, and social impacts. The installation of food waste disposers emerged as a primary strategy for source-separated food waste transfer to wastewater treatment systems through municipal pipelines. However, this approach accelerated the transformation of sewer systems into bioreactors and induced sewer pipe deterioration. Therefore, a novel microencapsulation method was developed and optimized to rapidly immobilize comminuted food waste particles. The stability of FW-encapsulated microcapsules was evaluated for their capacity to suppress organic leaching, destabilize functional biofilm architectures, and mitigate hazardous gas emissions and pipeline blockages in sewer systems during sewage conveyance. Results showed that FW-loaded microcapsules exhibited physicochemical stability against hydrodynamic shear and microbial degradation during sewer transport. It suppressed 33.62 mg/L organic matter release based on COD, reduced fluorescent substance accumulation/degradation, and limited macromolecular organics leakage. Microencapsulation destabilized sewer biofilm integrity via EPS reduction, disrupted humic acid stabilization, altered microbial dominance, and induced protein conformational loosening, impairing biofilm resilience. The technology mitigated sewer risks by curbing 3078.3 ppm VOC. It eliminating 100 % and 98.80 % increments of CH₄ and CO compared to crushed FW discharge increments(2.55 mg/L and 0.09 mg/L), suppressing 0.80 mg/L sulfide conversion increments, and minimizing sedimentation through particle size and suspended solids control. Integration with food waste disposers enhanced source-segregated organic collection, optimized hydro-transport to alleviate pipe deterioration, reduced 0.915 MtCO₂-eq transport-related carbon emissions, and improved treatment efficiency of wastewater treatment plants. This microencapsulation strategy provided a sustainable solution for FW management, combining infrastructure preservation, emission control, and resource recovery.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"282 ","pages":"Article 123749"},"PeriodicalIF":11.4,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143889851","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":"Reversing and controlling microbial proliferation in the water system of a high-risk hospital ward after extended closure and reconstruction","authors":"Dominique L. Chaput ,&nbsp;Kerr Clarkson ,&nbsp;Linda Bagrade ,&nbsp;Aleksandra Marek ,&nbsp;Dennis Kelly ,&nbsp;David Watson ,&nbsp;Tom Steele ,&nbsp;Alistair Leanord","doi":"10.1016/j.watres.2025.123748","DOIUrl":"10.1016/j.watres.2025.123748","url":null,"abstract":"<div><div>Opportunistic premise plumbing pathogens occur naturally in water but can pose a health risk to hospital patients who are more vulnerable due to illness or treatment. Ward closure periods can lead to microbial proliferation within water systems, posing a challenge to hospital estates and infection control teams. Following the 3-year closure of our paediatric haemato-oncology ward, water testing showed high total viable counts (TVCs) in over 20 % of samples and elevated counts of numerous Gram negative bacterial species (GNBs) in 73 % of samples, despite daily flushing and continuous chlorine dioxide dosing. We aimed to determine the extent of microbial proliferation, measure the impact of three sequential interventions (system disinfections with chlorine, with silver stabilised hydrogen peroxide, and then tap replacement), and assess the long-term performance of this water system. By sampling systematically across spatial and temporal scales, and using a range of microbiological tests (TVCs, <em>Legionella</em> spp., <em>Pseudomonas</em> spp., Gram negative bacteria, atypical mycobacteria and fungi), we showed that microbial proliferation was confined to the closed ward. Chlorine treatment had no significant impact on TVCs, but both silver stabilised hydrogen peroxide and tap replacement resulted in significant decreases (<em>p</em> &lt; 0.01). Similarly, the three Gram negative species that were enriched following the reconstruction period (<em>Cupriavidus pauculus, Sphingomonas paucimobilis</em>, and <em>Acidovorax temperans</em>) were less impacted by chlorine than by the other interventions. Following these interventions, fewer than 1 % of samples exceeded our strict local TVC threshold of 10 CFU/ml and GNBs were detected in 7 % of samples. Since the ward reopened to patients in 2022, there has been no return of the high microbiological counts observed immediately after reconstruction. Gram negative bacteria have been detected only sporadically, and the taxa found in samples collected through 0.2 μm point-of-use filters shifted towards species associated with humans. Our systematic approach was successful in returning this hospital water system to a safe state, and once microbial proliferation within the system itself was rectified, further positive results were likely attributable to the interactions of users with the outlets. Distinguishing between possible sources of microbial counts in water is crucial to selecting the most suitable interventions and helping ensure provision of safe water to patients.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"282 ","pages":"Article 123748"},"PeriodicalIF":11.4,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143885367","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":"Viruses in human-impacted estuarine ecotones: Distribution, metabolic potential, and environmental risks","authors":"Yunmeng Chu ,&nbsp;Xiaoxiao Dong ,&nbsp;Shiyun Fang ,&nbsp;Lihong Gan ,&nbsp;Xuezhu Lee ,&nbsp;Lei Zhou","doi":"10.1016/j.watres.2025.123750","DOIUrl":"10.1016/j.watres.2025.123750","url":null,"abstract":"<div><div>Estuaries, as dynamic ecological interfaces between marine and terrestrial systems, are characterized by high productivity and intricate microbial communities. Viruses exert critical regulatory effects on microbial processes, influencing ecological functions and contributing to environmental dynamics in estuarine ecosystems. Despite their significance, the diversity and ecological roles of estuarine viruses remain insufficiently understood. This study explored the viral biogeographic patterns, metabolic potential, and influencing factors in 30 subtropical estuaries in China. Few estuarine viruses (&lt; 22 %) exhibited homology with known viruses, and the low overlap of virus clusters with other environments highlights their novelty and habitat specificity. Mantel tests and random forest analysis identified salinity, temperature, nutrients, and pollutants as key factors influencing viral composition and functional profiles. In addition, correlation analysis between virus and host confirmed significant virus-host interactions, while functional analyses highlighted the role of environmental conditions and horizontal gene transfer in shaping auxiliary metabolic genes linked to elemental biogeochemical cycles, particularly phosphorus, sulfur, and nitrogen. The detection of antibiotic resistance genes (ARGs) and virulence factors (VFs) within viral genomes underscores the role of viruses as reservoirs of ARGs and VFs in these ecosystems. These results demonstrate the profound influence of abiotic and host factors on viral community structures in subtropical estuarine ecotones and underscore the ecological significance of metabolic genes in biogeochemical cycling. By clarifying these interactions, this study advances the understanding of viral contributions to ecosystem functioning and biogeochemical dynamics in estuarine environments.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"282 ","pages":"Article 123750"},"PeriodicalIF":11.4,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143889918","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 Nature-Inspired Metal-Free Electrocatalyst towards Efficient Electron Transfer and Robust Cascade Oxygen Reduction for Wastewater Treatment","authors":"Yao Pan, Xudong Yang, Zhe Wang, Yu Han, Junxi Guo, Ran Yin, Shanyuan Niu, Dan Shan, Lili Ding, Jinfeng Wang, Hongqiang Ren","doi":"10.1016/j.watres.2025.123747","DOIUrl":"https://doi.org/10.1016/j.watres.2025.123747","url":null,"abstract":"The pressing demand for removing high-risk emerging contaminants from wastewater calls for tailored treatment strategies, for which heterogeneous electrocatalysis induced by cascade oxygen reduction reaction (ORR) holds considerable potential. This process, however, suffers from poor interfacial electron transfer and discounted performance in non-acidic conditions. Inspired by the electron respiration chain of cells, a metal-free, quinone-based catalyst (PBth-BQ) was innovatively designed and synthesized. With excellent redox reversibility over 50 cycles and no risk of metal leaching, it boosted the direct electron transfer by 110% compared to the bare graphite substrate and facilitated cascade ORR to generate ·OH for effective contaminant abatement in the pH range of 3-13. Among them, pH 8 demonstrated the best performance, which is suitable for wastewater treatment. In particular, PBth-BQ performed well as both anodic and cathodic electrodes in azithromycin mineralization with different oxygen donors, verified by the <em>in-situ</em> mass spectrum. Considering the abundance of quinone-like structures in oxidized carbon materials, this biomimetic design may inspire the further exploration of cheap and efficient electrocatalysts for wastewater treatment.","PeriodicalId":443,"journal":{"name":"Water Research","volume":"18 1","pages":""},"PeriodicalIF":12.8,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143885369","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}