Water Research最新文献

{"title":"An integrated framework of deep learning and entropy theory for enhanced high-dimensional permeability field identification in heterogeneous aquifers","authors":"Mingxu Cao ,&nbsp;Zhenxue Dai ,&nbsp;Junjun Chen ,&nbsp;Huichao Yin ,&nbsp;Xiaoying Zhang ,&nbsp;Jichun Wu ,&nbsp;Hung Vo Thanh ,&nbsp;Mohamad Reza Soltanian","doi":"10.1016/j.watres.2024.122706","DOIUrl":"10.1016/j.watres.2024.122706","url":null,"abstract":"<div><div>Accurately estimating high-dimensional permeability (<strong><em>k</em></strong>) fields through data assimilation is critical for minimizing uncertainties in groundwater flow and solute transport simulations. However, designing an effective monitoring network to obtain diverse system responses in heterogeneous aquifers for data assimilation presents significant challenges. To investigate the influence of different measurement types (hydraulic heads, solute concentrations, and permeability) and monitoring strategies on the accuracy of permeability characterization, this study integrates a deep learning-based surrogate modeling approach and the entropy-based maximum information minimum redundancy (MIMR) monitoring design criterion into a data assimilation framework. An ensemble MIMR-optimized method is developed to provide more comprehensive monitoring information and avoid missing key information due to the randomness of stochastic response datasets in entropy analysis. A numerical case of solute transport with log-Gaussian permeability fields is presented, with twelve scenarios designed by combining different measurement types and monitoring strategies. The results demonstrated that the proposed ensemble MIMR-optimized method significantly improved the <strong><em>k</em></strong>-field estimates compared to the conventional MIMR method. Additionally, high prediction accuracy in forward modeling is essential for ensuring reliable inversion results, especially for observation data with strong nonlinearity. The findings of this study enhance our understanding and management of <strong><em>k</em></strong>-field estimation in heterogeneous aquifers, contributing to the development of more robust inversion frameworks for general data assimilation tasks.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"268 ","pages":"Article 122706"},"PeriodicalIF":11.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142542116","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":"Wane-and-wax mechanism of nitrogenous disinfection byproducts with constant Cl/N peak under UV/chlorine treatment: Implication for new drinking water disinfection strategy","authors":"Jinxiu Lou ,&nbsp;Lu Yin ,&nbsp;Feilong Dong ,&nbsp;Zhanfei He ,&nbsp;Huijie Lu ,&nbsp;Shuangxi Fang ,&nbsp;Xiangliang Pan","doi":"10.1016/j.watres.2024.122651","DOIUrl":"10.1016/j.watres.2024.122651","url":null,"abstract":"<div><div>Nitrogenous disinfection byproducts (N-DBPs) are notorious for their serious health risks, yet nitrate (NO₃^-) mediates N-DBPs generation during UV/chlorine treatment remains unexplored. This study investigated the interaction of chlorine and NO₃^- on N-DBPs formation and developed a specific fragment-based screening method using UPLC-QTOF-MS to explore the underlying mechanism. Results showed that the chlorine-to-nitrogen (Cl/NO₃^--N) molar ratio significantly affects dichloroacetonitrile (DCAN) and dichloroacetamide (DCAM) generation, with peak concentrations at a Cl/NO₃^--N molar ratio of around 15. NO₃^- promotes the production of HO^•, which positively correlates with DCAN and DCAM concentrations, also peaking at this ratio. Utilizing our developed method, three key hydroxyl-substituted intermediates that circumvent the previously reported “limiting-steps” in DCAN formation were identified. This reaction proceeds via a stepwise mechanism involving hydroxylation and chlorine substitution to produce hydroxyl-phenylacetonitrile and hydroxyl-chlorine-phenylacetonitrile. The conversion rate of hydroxyl-chlorine-phenylacetonitrile to DCAN was 8.6 times higher at Cl/NO₃^--N molar ratio of 15 compared to conditions without NO₃^-, attributed to the weakened bond strength of the side chain, as supported by density functional theory calculations. This study provides novel insights into the mechanistic pathways of DCAN and DCAM formation, critical for developing more effective drinking water disinfection technologies to control N-DBPs.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"268 ","pages":"Article 122651"},"PeriodicalIF":11.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142542638","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":"Electric syntrophy-driven modulation of Fe0-dependent microbial denitrification","authors":"Tianyu Gao ,&nbsp;Ying Li ,&nbsp;Ke Dai ,&nbsp;Fangang Meng","doi":"10.1016/j.watres.2024.122722","DOIUrl":"10.1016/j.watres.2024.122722","url":null,"abstract":"<div><div>In natural or engineered anaerobic environments, iron oxidation-driven microbial denitrification plays a critical role in the water or wastewater treatment. Herein, we report a previously unidentified metallic iron (Fe⁰)-dependent denitrification mode driven by the electro-syntrophic interaction between electroactive microorganism and denitrifier. In a model denitrifying consortium of <em>Shewanella oneidensis</em> and <em>Pseudomonas aeruginosa</em>, we find that <em>P. aeruginosa</em> can accept electrons for nitrate reduction via the constructed electron transfer system of Fe⁰–<em>S. oneidensis</em>–<em>P. aeruginosa</em>. In the electro-syntrophic consortium, the membrane-bound CymA–OmcA–MtrC protein complexes of <em>S. oneidensis</em> drive the generation, transfer and consumption of electrons, thus enabling modulation of microbial metabolic activity. Specially, using Fe⁰ as the sole electron donor, <em>S. oneidensis</em> can act as a bio-engine to harvest electrons and conserve energy from Fe⁰ biocorrosion. Electrons released by <em>S. oneidensis</em> are utilized by <em>P. aeruginosa</em> for accomplishing microbial denitrification. Metatranscriptomics analysis demonstrated that the direct electron cross-feeding process facilitates the expression of genes encoding for denitrification enzymes, intracellular electron transfer proteins, and quorum sensing of <em>P. aeruginosa</em>. The Fe⁰-dependent electronic syntrophy in this work could provide a metabolic window for the growth of denitrifiers that is a new insight into nitrate removal or global nitrogen cycle.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"268 ","pages":"Article 122722"},"PeriodicalIF":11.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142541595","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":"Greater environmental risk of shale gas produced water from lacustrine than marine sources in Fuling shale gas field, China: Insights from inorganic compounds, dissolved organic matter, and halogenated organic compounds","authors":"Hualiang Feng ,&nbsp;Yani Lai ,&nbsp;Xiaojun Wang ,&nbsp;Zhaoji Zhang ,&nbsp;Shaohua Chen","doi":"10.1016/j.watres.2024.122719","DOIUrl":"10.1016/j.watres.2024.122719","url":null,"abstract":"<div><div>Lacustrine shale gas represents a promising frontier in the future development of shale gas resources. However, research on the characterization of lacustrine shale gas produced water (SGPW) remains scarce. In this study, we characterized the geochemical properties of both marine and lacustrine SGPW (MSGPW and LSGPW) and assessed their dissolved organic matter (DOM) components using fluorescence EEM spectroscopy. Additionally, we employed Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to analyze halogenated organic compounds (HOCs) and non-HOCs in SGPW, as well as their transformations during storage in open impoundments. Pollutants in LSGPW generally had higher concentrations and greater fluctuations compared to those in MSGPW. Our findings from EEM spectroscopy and FT-ICR MS revealed that phenolic compounds may be important components of DOM in all SGPW. Moreover, the number of detected unique molecules in LSGPW was greater than in MSGPW. CHO or CHOS compounds dominated in non-HOCs, with LSGPW exhibiting generally higher DBE, modified aromaticity index (AI_mod), nominal oxidation state of carbon (NOSC), double bond equivalent minus oxygen per carbon ((DBE-O)/C) values, and lower H/C values compared to MSGPW, while unsaturated aliphatic compounds typically dominated in HOCs. Furthermore, we employed 37 transformation reactions that might occur during SGPW storage and found that oxygen addition and dealkyl group reactions were predominant, with these two types of reactions occurring more frequently in LSGPW than in MSGPW. LSGPW exhibited higher toxicity compared to MSGPW, with toxicity positively correlated with the concentrations of inorganic salts and organic substances with higher AI_mod, NOSC, and (DBE-O)/C. These findings contribute to a more comprehensive understanding of LSGPW, enabling the design and implementation of more rational disposal measures to effectively mitigate its potential environmental risks.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"268 ","pages":"Article 122719"},"PeriodicalIF":11.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142541849","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":"The reverse-reduction effect of dissolved organic matter on the degradation of micropollutants induced by halogen radicals (Cl2•- and Br2•-)","authors":"Shuangshuang Cheng ,&nbsp;Rui Cui ,&nbsp;Yangjian Zhou ,&nbsp;Yu Lei ,&nbsp;Ni Wang ,&nbsp;Yanheng Pan ,&nbsp;Xin Yang","doi":"10.1016/j.watres.2024.122720","DOIUrl":"10.1016/j.watres.2024.122720","url":null,"abstract":"<div><div>Reactive halogen radicals (e.g., Cl₂^•- and Br₂^•-) greatly impact the degradation of micropollutants in natural waters and engineered water treatment systems. The ubiquitous dissolved organic matter (DOM) in real waters is known to greatly inhibit the degradation of micropollutants by reducing micropollutant's intermediate (i.e., TC^•+/TC(-H)^•), however, such DOM's effects on the halogen-radical-induced system have not been understood yet. The present study focuses on investigating and quantifying such inhibitory effects of DOM during Cl₂^•-- and Br₂^•--mediated process. Guanosine (Gs) was selected as a model compound. The transient spectra show that Cl₂^•- and Br₂^•- react with Gs generating intermediates (i.e., Gs^•+/Gs(-H)^•) via single-electron transfer. In the presence of 1.0 mg_C <span>L</span>^-1 DOM, over 70% of this oxidized Gs was reduced back to Gs. Comparing the extent of reverse-reduction inhibitory among different reaction systems, this inhibitory in Br₂^•- system was slightly lower than that in Cl₂^•- and SO₄^•- system, corresponding the slightly difference of inhibition factor (IF) values as SO₄^•- &lt; Cl₂^•- &lt; Br₂^•-. The reverse-reduction effect of DOM was further quantified for 19 common micropollutants. It varied significantly with IF values of 0.21–1.26 and 0.28–1.40 in Cl₂^•-- and Br₂^•--mediated process, respectively. Purines and amines generally exhibited more pronounced inhibition than phenols in both systems. A good correlation of IF values with micropollutant's reduction potential was observed, which can be applied to predict the degradation of more unstudied micropollutants. This study highlights the important role of the reverse-reduction effect of DOM on micropollutant degradation. It can significantly improve the accuracy in predicting degradation rate in advanced oxidation processes for treating water containing halides.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"268 ","pages":"Article 122720"},"PeriodicalIF":11.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142541597","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":"The shifts in microbial interactions and gene expression caused by temperature and nutrient loading influence Raphidiopsis raciborskii blooms","authors":"Baohai Zheng ,&nbsp;Ling Zhou ,&nbsp;Jinna Wang ,&nbsp;Peichang Dong ,&nbsp;Teng Zhao ,&nbsp;Yuting Deng ,&nbsp;Lirong Song ,&nbsp;Junqiong Shi ,&nbsp;Zhongxing Wu","doi":"10.1016/j.watres.2024.122725","DOIUrl":"10.1016/j.watres.2024.122725","url":null,"abstract":"<div><div>Climate change and the trophic status of water bodies are important factors in global occurrence of cyanobacterial blooms. The aim of this study was to explore the cyanobacteria‒bacterial interactions that occur during <em>Raphidiopsis raciborskii</em> (<em>R. raciborskii</em>) blooms by conducting microcosm simulation experiments at different temperatures (20 °C and 30 °C) and with different phosphorus concentrations (0.01 mg/L and 1 mg/L) using an ecological model of microbial behavior and by analyzing microbial self-regulatory strategies using weighted gene coexpression network analysis (WGCNA). Three-way ANOVA revealed significant effects of temperature and phosphorus on the growth of <em>R. raciborskii</em> (<em>P</em> &lt; 0.001). The results of a metagenomics-based analysis of bacterioplankton revealed that the synergistic effects of both climate and trophic changes increased the ability of <em>R. raciborskii</em> to compete with other cyanobacteria for dominance in the cyanobacterial community. The antagonistic effects of climate and nutrient changes favored the occurrence of <em>R. raciborskii</em> blooms, especially in eutrophic waters at approximately 20 °C. The species diversity and richness indices differed between the eutrophication treatment group at 20 °C and the other treatment groups. The symbiotic bacterioplankton network revealed the complexity and stability of the symbiotic bacterioplankton network during blooms and identified the roles of key species in the network. The study also revealed a complex pattern of interactions between cyanobacteria and non-cyanobacteria dominated by altruism, as well as the effects of different behavioral patterns on <em>R. raciborskii</em> bloom occurrence. Furthermore, this study revealed self-regulatory strategies that are used by microbes in response to the dual pressures of temperature and nutrient loading. These results provide important insights into the adaptation of microbial communities in freshwater ecosystems to environmental change and provide useful theoretical support for aquatic environmental management and ecological restoration efforts.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"268 ","pages":"Article 122725"},"PeriodicalIF":11.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142542073","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":"Corrigendum to “A comprehensive analysis of submarine groundwater discharge and nutrient fluxes in the Bohai Sea, China”","authors":"Xiaolang Zhang ,&nbsp;Hailong Li ,&nbsp;Xuejing Wang ,&nbsp;Xingxing Kuang ,&nbsp;Yan Zhang ,&nbsp;Kai Xiao ,&nbsp;Chao Xu","doi":"10.1016/j.watres.2024.122659","DOIUrl":"10.1016/j.watres.2024.122659","url":null,"abstract":"","PeriodicalId":443,"journal":{"name":"Water Research","volume":"268 ","pages":"Article 122659"},"PeriodicalIF":11.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142542074","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":"Impacts of blending advanced treated water and traditional groundwater supply on lead and copper concentrations and microbial diversity in premise plumbing","authors":"Anushka Mishrra ,&nbsp;Lin Zhang ,&nbsp;Janelle Junior ,&nbsp;Fangqiong Ling ,&nbsp;Nicole K. Blute ,&nbsp;Daniel E. Giammar","doi":"10.1016/j.watres.2024.122726","DOIUrl":"10.1016/j.watres.2024.122726","url":null,"abstract":"<div><div>In response to stresses on water demands, some regions augment conventional drinking water sources with alternative water supplies such as desalinated seawater and reclaimed wastewater. The advanced treatment of wastewater by reverse osmosis, microfiltration, and advanced oxidation processes can produce high quality water for potable uses. However, if not appropriately stabilized, the resulting water can be corrosive to metal-based distribution pipes and plumbing materials. We conducted long-term premise plumbing pipe loop experiments with copper pipes containing lead solder to test the impact of the introduction of advanced treated water on the water quality. Advanced treated water (ATW) originally at low pH (&lt;7) and low alkalinity (&lt;10 mg/L as CaCO₃) was stabilized with a calcite contactor before being blended with baseline ground water (BLW). The effects of percentages of ATW on the release of lead and copper and on the changes in the microbial diversity were monitored. Experiments monitored metal release from pipes receiving (1) only BLW, (2) a series of blends of BLW and ATW that gradually increased from 25 % to 100 % ATW, and (3) an abrupt switch from BLW to 100 % ATW. Introducing 100 % ATW dramatically increased lead release and simultaneously decreased copper release. Pipe scale analysis showed that the introduction of ATW had destabilized sulfate-containing pipe scales, which exposed the copper pipe surface to galvanic corrosion. The dissolution of scale material was associated with a significant decrease in sulfate concentration in the 100 % ATW which was in agreement with theoretical solubility calculations. The impact of blending ATW on microbial diversity was studied via 16S rRNA gene amplicon sequencing. The composition of the microbial communities changed significantly after water was in contact with the copper pipes in experiments with both BLW and ATW. The type of water recirculating in the pipes affected the structure of the microbial community. The results from this study can be useful for water utilities that are considering potable reuse as they develop strategies to mitigate any adverse impacts of water quality changes.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"268 ","pages":"Article 122726"},"PeriodicalIF":11.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142542048","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":"Electrocoagulation treatment of wastewater collected from Haldia industrial region: Performance evaluation and comparison of process optimization","authors":"Uma Sankar Behera ,&nbsp;Sourav Poddar ,&nbsp;Hun-Soo Byun","doi":"10.1016/j.watres.2024.122716","DOIUrl":"10.1016/j.watres.2024.122716","url":null,"abstract":"<div><div>This study investigates the treatment of oil-contaminated wastewater with high levels of inorganic substances, suspended solids and turbidity, collected from the Haldia industrial region of India in February 2023. The wastewater, originating from industries such as chemical, petrochemical, textile, and battery manufacturing, presents a complex pollutant load that challenges traditional treatment methods. Electrocoagulation was employed as the treatment technique, with process optimization conducted using Box-Behnken design (BBD) and central composite design (CCD) for key parameters: pH, initial oil concentration, current density, and electrolysis time. The study comprehensively examined the effects of these parameters on turbidity removal. The optimal conditions were determined to be a pH of 7.5, an initial oil concentration of 275 mg/L, a current density of 17.5 mA/cm², and an electrolysis time of 20 min. Under these conditions, CCD outperformed BBD, achieving a desirability score of 93 % compared to 80 % for BBD. The process successfully reduced turbidity from 450 NTU to 56 NTU and total suspended solids (TSS) from 300 mg/L to 102 mg/L. The operation cost of the process was found to range from ₹0.904/m³ to ₹2.71/m³ as the electrolysis time increased from 0.17 to 0.5 h. The study presents a viable solution for industrial wastewater treatment in this region, aligning with the United Nations Sustainable Development Goal (UN SDG) 2030. Additionally, combining electrocoagulation with membrane filtration may enhance comprehensive pollutant removal.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"268 ","pages":"Article 122716"},"PeriodicalIF":11.4,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142541599","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":"Characterization of PFOA isomers from PFAS precursors and their reductive defluorination","authors":"Jun Sun ,&nbsp;Wanutcha Lorpaiboon ,&nbsp;Nicholas Fox ,&nbsp;Adele Jones ,&nbsp;Junming Ho ,&nbsp;Michael J. Manefield ,&nbsp;Naresh kumar ,&nbsp;Denis O'Carroll ,&nbsp;Matthew Lee","doi":"10.1016/j.watres.2024.122717","DOIUrl":"10.1016/j.watres.2024.122717","url":null,"abstract":"<div><div>Perfluorooctanoic acid (PFOA) including linear and branched isomers is one of only three PFAS included in the Stockholm convention on Persistent Organic Pollutants. Unfortunately, PFOA branched isomers have received less attention than the linear due to analytical difficulties and perceived lower environmental concentrations. In this study, we revealed a environmentally relevant pathway for the formation of branched PFOA from PFAS precursors. AFFF samples showed a doubling of branched PFOA concentrations (138 mg/L) after TOP assay oxidation (307 mg/L). These findings indicate that branched PFOA may be more pervasive in the environment than previously thought. Additionally, we investigated the reductive degradability of PFOA using vitamin B12 (VB₁₂) (a naturally occurring electron shuttle) in combination with either zero-valent zinc (ZVZ) or zero-valent iron (ZVI). Linear PFOA, as well as two branched isomers (3-methyl PFOA and 5,5-dimethyl PFOA), resisted reductive defluorination under the experimental conditions. However, all other branched isomers degraded within 10 days in the ZVZ-VB₁₂ system. The experimental rate constants for specific PFOA isomers generally correlate with their calculated reduction potentials, except for 6-methyl PFOA. A potential defluorination pathway was proposed based on high-resolution mass spectrometry (LC-Orbitrap) and density functional theory (DFT) studies.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"268 ","pages":"Article 122717"},"PeriodicalIF":11.4,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142536572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}