Environmental Science: Processes & Impacts最新文献

{"title":"Associations between traffic-related air pollution and allergic rhinitis outpatient visits in three cities of Gansu Province†","authors":"Hongran Ma, Furong Qu, Jiyuan Dong and Jiancheng Wang","doi":"10.1039/D4EM00234B","DOIUrl":"10.1039/D4EM00234B","url":null,"abstract":"<p >Emerging evidence indicates an increasing prevalence of allergic rhinitis (AR), potentially linked to air quality. The aim of the present study was to assess the relationship between traffic-related air pollutants (TRAPs) and outpatient visits for AR. Daily outpatient data for AR, air pollutant concentrations, and meteorological data were collected from January 2018 to December 2020 in Dingxi, Longnan, and Tianshui. Utilizing a Quasi-Poisson distribution, a generalized additive model (GAM) was employed in conjunction with distributed lag non-linear models (DLNM) to explore the association and lag effects of TRAPs on AR outpatient visits across the three cities. Stratified analyses based on gender, age, and season were conducted. A total of 11 106 outpatient visits for AR were recorded in the three cities. For an increase of 10 μg m<small>⁻³</small> in PM<small>_2.5</small>, the effect estimates in Dingxi, Longnan, and Tianshui reached their maximum at lag04, lag06, and lag07, respectively, with relative risk (RR) values of 4.696 (95% CI: 1.890, 11.614), 2.842 (95% CI: 2.102, 4.922), and 1.102 (95% CI: 1.066, 1.140). For NO<small>₂</small>, the highest associations were exhibited in Dingxi (RR = 1.262, 95% CI: 1.081, 1.473) at lag07, in Longnan (RR = 2.554, 95% CI: 2.100, 4.805) at lag06, and in Tianshui (RR = 1.158, 95% CI: 1.106, 1.213) at lag07. Meanwhile, the strongest effects observed for a 1 mg m<small>⁻³</small> increase in CO were 2.786 (95% CI: 1.467, 5.291) for Dingxi at lag07, 1.502 (95% CI: 1.096, 2.059) for Longnan at lag05, and 1.385 (95% CI: 1.137, 1.686) for Tianshui at lag04. Adults aged 15–64 years appeared to be more susceptible to TRAPs, and the associations were stronger in the cold season. The results of the present study indicate that exposure to TRAPs was positively correlated with outpatient visits for AR.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 9","pages":" 1618-1628"},"PeriodicalIF":4.3,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141896134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Emerging investigator series: predicted losses of sulfur and selenium in european soils using machine learning: a call for prudent model interrogation and selection†","authors":"Gerrad D. Jones, Logan Insinga, Boris Droz, Aryeh Feinberg, Andrea Stenke, Jo Smith, Pete Smith and Lenny H. E. Winkel","doi":"10.1039/D4EM00338A","DOIUrl":"10.1039/D4EM00338A","url":null,"abstract":"<p >Reductions in sulfur (S) atmospheric deposition in recent decades have been attributed to S deficiencies in crops. Similarly, global soil selenium (Se) concentrations were predicted to drop, particularly in Europe, due to increases in leaching attributed to increases in aridity. Given its international importance in agriculture, reductions of essential elements, including S and Se, in European soils could have important impacts on nutrition and human health. Our objectives were to model current soil S and Se levels in Europe and predict concentration changes for the 21st century. We interrogated four machine-learning (ML) techniques, but after critical evaluation, only outputs for linear support vector regression (Lin-SVR) models for S and Se and the multilayer perceptron model (MLP) for Se were consistent with known mechanisms reported in literature. Other models exhibited overfitting even when differences in training and testing performance were low or non-existent. Furthermore, our results highlight that similarly performing models based on RMSE or <em>R</em><small>²</small> can lead to drastically different predictions and conclusions, thus highlighting the need to interrogate machine learning models and to ensure they are consistent with known mechanisms reported in the literature. Both elements exhibited similar spatial patterns with predicted gains in Scandinavia <em>versus</em> losses in the central and Mediterranean regions of Europe, respectively, by the end of the 21st century for an extreme climate scenario. The median change was −5.5% for S (Lin-SVR) and −3.5% (MLP) and −4.0% (Lin-SVR) for Se. For both elements, modeled losses were driven by decreases in soil organic carbon, S and Se atmospheric deposition, and gains were driven by increases in evapotranspiration.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 9","pages":" 1503-1515"},"PeriodicalIF":4.3,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141887594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Identifying initial transformation products during chlorination of the indole moiety and unveiling their formation mechanisms†","authors":"MengXue Huan, Yong Dong Liu and Rugang Zhong","doi":"10.1039/D4EM00196F","DOIUrl":"10.1039/D4EM00196F","url":null,"abstract":"<p >To identify toxicity drivers within poorly characterized high-molar-weight disinfection by-products (DBPs), relatively stable high-yield initial transformation products generated from aromatic amino acids and peptides and humic substances have drawn much attention. In this study, initial transformation products in chlorination of the indole moiety in tryptophan (<strong>Trp</strong>) are proposed and their formation mechanisms were investigated using a quantum chemical computational method. The results indicate that <strong>3-Cl-Trp<small>⁺</small></strong> is initially formed after the Cl<small>⁺</small> of HOCl attacks the indole moiety, and nucleophilic addition with nucleophilic agents (H<small>₂</small>O and OCl<small>⁻</small>) is thermodynamically preferred over deprotonation to generate <strong>2-X-3-Cl-indoline</strong> moiety (X = OH and OCl), which is in contrast to indole. Over 25 types of initial transformation products are proposed from the <strong>2-X-3-Cl-indoline</strong> moiety and two ring opening pathways were found at N1–C2 and C2–C3 bonds. Significantly, most structures of initial transformation products proposed based on experimental detection <em>m/z</em> values were confirmed using quantum chemical calculations and some new products are proposed in this work. The results are helpful to expand our understanding of the intrinsic reactivity of aromatic ring towards chlorination by hypochlorous acid.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 9","pages":" 1629-1640"},"PeriodicalIF":4.3,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141872817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Vehicular pollution as the primary source of oxidative potential of PM2.5 in Bhubaneswar, a non-attainment city in eastern India†","authors":"Subhasmita Panda, Chinmay Mallik, S. Suresh Babu, Sudhir Kumar Sharma, Tuhin Kumar Mandal, Trupti Das and R. Boopathy","doi":"10.1039/D4EM00150H","DOIUrl":"10.1039/D4EM00150H","url":null,"abstract":"<p >We assessed the oxidative potential (OP) of PM<small>_2.5</small> (<em>n</em> = 230) using dithiothreitol (DTT) assay to identify the major emission sources in Bhubaneswar (20.20°N, 85.80°E), one of the non-attainment cities under the National Clean Air Program, situated on the eastern coast of India. Continuous day and night PM<small>_2.5</small> samples were collected during periods influenced by marine airmass (MAM; April–May 2019) as well as continental airmass (CAM; October 2019–December 2019). Volume normalized DTT (DDTv) activities were approximately two times higher during CAM compared to MAM periods. In contrast, mass normalized DTT activity (DDTm) showed insignificant variations between CAM and MAM periods. This might be due to particulate organic matter, which accounted for more than one-fifth of the PM<small>_2.5</small> mass loading and remained surprisingly invariant during the study periods. Positive matrix factorization (PMF) identified secondary aerosols (MAM: 26% and CAM: 33%) as dominant contributors to PM<small>_2.5</small> mass in both periods. OP, is, however, dominated by vehicular emissions (21%) as identified through multiple linear regression. Conditional Bivariate Probability Function (CBPF) analysis indicated that local sources were the primary drivers for the catalytic activity of PM<small>_2.5</small> in the study region. Additionally, stagnant meteorological conditions, combined with the chemical aging of species during regional transport of pollutants, likely enhanced redox activity of PM<small>_2.5</small> during the CAM period. The study highlights that increasing traffic congestion is primarily responsible for adverse health outcomes in the region. Therefore, it is important to regulate mobility and vehicular movement to mitigate the hazardous impact of PM<small>_2.5</small> in Bhubaneswar.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 10","pages":" 1716-1735"},"PeriodicalIF":4.3,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141863021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Molecular characteristics of organic matter derived from sulfonated biochar†","authors":"Zhengfeng Jiang, Chen He, Fei Gao, Quan Shi, Yang Chen, Haimeng Yu, Zhimao Zhou and Ruoxin Wang","doi":"10.1039/D4EM00233D","DOIUrl":"10.1039/D4EM00233D","url":null,"abstract":"<p >Sulfonated biochar (SBC), as a functional carbon-based material, has attracted widespread attention due to its excellent adsorption properties. The composition of biochar-derived organic matter (B-DOM) is a key factor influencing the migration and transformation of soil elements and pollutants. However, molecular characteristics of sulfonated biochar-derived organic matter (SBC-DOM) are still unclear. In this study, the molecular composition of derived organic matter (DOM) from SBC prepared <em>via</em> one-step carbonization-sulfonation techniques was investigated by Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and then compared with those of DOMs from rice husk (RH), pyrochar (PYC), and hydrochar (HYC). The results show that the CHOS- and CHONS-containing formulae are predominant in SBC-DOM, accounting for 85% of the total molecular formula number, while DOMs from RH, PYC, and HYC are dominated by CHO-containing formulae. Compared to PYC-DOM and HYC-DOM, SBC-DOM has more unsaturated aliphatic compounds, which make it more labile and easily biodegraded. Additionally, SBC-DOM has higher O/C, (N + O)/C ratios and sulfur-containing compounds. These findings provide a theoretical basis for further research on the application of sulfonated biochar in soil improvement and remediation.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 9","pages":" 1641-1650"},"PeriodicalIF":4.3,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141873403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"More than just sweet: current insights into microplastics in honey products and a case study of <i>Melipona quadrifasciata</i> honey.","authors":"Bárbara Rani-Borges, Mariana Victorino Nicolosi Arena, Ingrid Naiara Gomes, Luís Henrique França de Carvalho Lins, Livia de Souza Camargo Cestaro, Marcelo Pompêo, Rômulo Augusto Ando, Isabel Alves-Dos-Santos, Rogério Hartung Toppa, Marcos Roberto Martines, Lucas Gonçalves Queiroz","doi":"10.1039/d4em00262h","DOIUrl":"https://doi.org/10.1039/d4em00262h","url":null,"abstract":"<p><p>Honey, traditionally known as a pure and natural substance, has become an unexpected reservoir for microplastic contamination. This study consisted of an experimental investigation to assess the occurrence of microplastics in honey produced by <i>Melipona quadrifasciata</i>, a native bee species in Brazil. Our investigation covers eight areas (one sample per area), including built and vegetated areas located in São Paulo city, Brazil, to understand the distribution of microplastics in these environments. Honey samples (10 mL) were collected using a syringe and sent to the laboratory for further analysis. Microplastics extracted from honey samples were characterized under a stereomicroscope to determine their size, color, and morphology. Also, the polymer type was determined by FTIR analysis. All honey samples (100%) showed microplastics. The predominant particles displayed a fiber shape with a size below 299 μm and a transparent color and were primarily composed of polypropylene. Their concentrations ranged from 0.1 to 2.6 particles per mL of honey, raising concerns about their potential impact on bee populations and human consumers. This study underscores the need for further research on the sources and implications of microplastic contamination in <i>Melipona quadrifasciata</i> honey, shedding light on the broader issue of environmental plastic pollution and its impact on pollinators.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141786541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Comprehensive assessment of per and polyfluoroalkyl substances (PFAS) contamination in groundwater of Kamrup, Assam, India: occurrence, health risks, and metabolomic insights†","authors":"Aditya Sharma, Sachin B. Jorvekar, Sujoy Bhowmik, Purusottam Mohapatra and Roshan M. Borkar","doi":"10.1039/D4EM00159A","DOIUrl":"10.1039/D4EM00159A","url":null,"abstract":"<p >Per-and polyfluoroalkyl substances (PFAS) are synthetic chemicals that are known for their environmental persistence and adverse health effects. This study comprehensively assessed PFAS contamination in the Kamrup region of Assam, India, focusing on its presence in groundwater and associated health risks. The analysis detected 12 PFAS in groundwater samples from both the Kamrup Metro and Rural regions. In Kamrup Rural, Perfluorohexanoic acid (PFHxA), perfluorononanoic acid (PFNA), and perfluorooctanesulfonic acid (PFOS) were prevalent, whereas in Kamrup Metro, PFNA and PFOS were dominant, based on detection frequencies. These findings are noteworthy, as they demonstrate the widespread presence of PFAS in groundwater, a vital source of drinking water in the region. The assessment of PFAS health risks in India involved hazard quotient calculations for different age groups. Perfluorobutanesulfonic acid (PFBS) posed the highest risk, ranking children &gt; boys &gt; men &gt; girls &gt; women. Overall, ∑PFAS had low hazard (HQ: 0.27–0.41). Further, this study assessed PFBS and PFOS toxicity in human kidney epithelial cell lines (HEK293T) cells, revealing that PFBS was more cytotoxic than PFOS. The study examined the metabolomics of HEK293T cells after PFBS exposure, revealing significant alterations in lipid metabolism, particularly glycerophospholipids, potentially affecting cellular function and health. These findings underscore the importance of monitoring PFAS contamination in drinking water sources, especially in regions such as Kamrup, where groundwater is a primary source. Our metabolomics results show significant health effects at the cellular level, raising concerns about the impact of PFAS exposure on human health. This study highlights PFAS contamination in Kamrup, Assam's groundwater and its health risks, providing valuable insights for policymakers and public health management.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 9","pages":" 1601-1617"},"PeriodicalIF":4.3,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141872818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Photodegradation of the main synthetic musk (HHCB) in water: kinetic study and influencing factors†","authors":"Hatice Turan, Mathieu Sebilo, Thierry Pigot and Mathilde Monperrus","doi":"10.1039/D4EM00351A","DOIUrl":"10.1039/D4EM00351A","url":null,"abstract":"<p >Galaxolide (HHCB) is the most common synthetic musk compound detected in numerous daily products. Despite its persistence in the aquatic environment, the photodegradation of HHCB remains poorly understood. In this study, we investigated the direct and indirect photolysis kinetics of HHCB under simulated sunlight and UVC light. Our aim was to determine the role of reactive oxygen species (ROS) responsible for HHCB degradation in the aquatic environment and to identify its transformation products. The influence of environmental factors on indirect photolysis was investigated by testing both synthetic waters (containing humic acid, carbonate (CO<small>₃</small><small>²⁻</small>), and nitrate (NO<small>₃</small><small>⁻</small>)) and real waters (riverine and effluent). Hydrogen peroxide (H<small>₂</small>O<small>₂</small>/UVC) was tested to simulate the wastewater treatment process. Quencher experiments were conducted to identify the role of ROS in HHCB photodegradation, including hydroxyl radicals (˙OH), carbonate radicals (CO<small>₃</small>˙<small>⁻</small>), triplet states of dissolved organic matter (<small>³</small>DOM*), and singlet oxygen (<small>¹</small>O<small>₂</small>). The results clearly indicated that HHCB was efficiently degraded by direct photolysis under both light conditions. The presence of H<small>₂</small>O<small>₂</small> led to the most efficient HHCB degradation due to the high production of ˙OH induced under UVC. Indirect photolysis contribution was observed, induced by ˙OH, CO<small>₃</small>˙<small>⁻</small>, <small>³</small>DOM*, and <small>¹</small>O<small>₂</small> to different extents depending on the light and matrix composition. The experiments led to the detection of transformation products: HHCB lactone, a well-known transformation product, and two other substances with proposed structures. This study provides a comprehensive identification of the processes involved in the direct and indirect photodegradation of HHCB, which could serve as the basis for evaluating and modeling the fate of HHCB in aquatic environments.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 9","pages":" 1571-1587"},"PeriodicalIF":4.3,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141863022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Oxidant concentrations and photochemistry in a vehicle cabin.","authors":"Pedro A F Souza, Corey R Kroptavich, Shan Zhou, Tara F Kahan","doi":"10.1039/d4em00319e","DOIUrl":"https://doi.org/10.1039/d4em00319e","url":null,"abstract":"<p><p>Indoor air quality (IAQ) in vehicles can be important to people's health, especially for those whose occupations require them to spend extensive time in vehicles. To date, research on vehicle IAQ has primarily focused on direct emissions as opposed to chemistry happening in vehicle cabins. In this work, we conducted time-resolved measurements of the oxidants and oxidant precursors ozone (O₃), nitric oxide (NO), nitrogen dioxide (NO₂), and nitrous acid (HONO) inside the cabin of a 2012 Toyota Rav4 under varying ventilation conditions (<i>i.e.</i>, car off, car on with passive ventilation, car on with mechanical ventilation <i>via</i> the recirculating fan, and car on with mechanical ventilation <i>via</i> the direct fan). Ozone levels inside the vehicle were significantly lower than outdoors under most conditions, and were approximately half the outdoor levels when the direct fan was in operation. Nitric oxide and NO₂ concentrations were very low both inside the vehicle and outdoors. Nitrous acid levels in the vehicle were lower than reported values in other indoor environments, though much higher than expected outdoor levels. We also investigated the potential for photochemical production of radicals in the vehicle. Time- and wavelength-resolved solar irradiance spectra were collected, and steady state hydroxyl radical (OH) and nitrate radical (NO₃) concentrations were calculated. Steady state OH concentrations were predicted to be similar to those in air masses in residences illuminated by sunlight, suggesting the importance of HONO photolysis in vehicles. Conversely, nitrate radicals (NO₃) were not considered significant indoor oxidants in our study due to rapid titration by NO. Overall, our findings emphasize the importance of both air exchange and photochemistry in shaping the composition of air inside vehicles.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141755711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Emerging investigator series: Coprecipitation with glucuronic acid limits reductive dissolution and transformation of ferrihydrite in an anoxic soil†","authors":"Laurel K. ThomasArrigo, Luiza Notini, Sophie Vontobel, Sylvain Bouchet, Tabea Nydegger and Ruben Kretzschmar","doi":"10.1039/D4EM00238E","DOIUrl":"10.1039/D4EM00238E","url":null,"abstract":"<p >Ferrihydrite, a poorly crystalline Fe(<small>III</small>)-oxyhydroxide, is abundant in soils and is often found associated with organic matter. Model studies consistently show that in the presence of aqueous Fe(<small>II</small>), organic carbon (OC)-associated ferrihydrite undergoes less transformation than OC-free ferrihydrite. Yet, these findings contrast microbial reductive dissolution studies in which the OC promotes the reductive dissolution of Fe(<small>III</small>) in ferrihydrite and leads to the release of associated OC. To shed light on these complex processes, we quantified the extent of reductive dissolution and transformation of native Fe minerals and added ferrihydrite in anoxic soil incubations where pure <small>⁵⁷</small>Fe-ferrihydrite (<small>⁵⁷</small>Fh), pure <small>⁵⁷</small>Fe-ferrihydrite plus dissolved glucuronic acid (<small>⁵⁷</small>Fh + GluC<small>_aq</small>), a <small>⁵⁷</small>Fe-ferrihydrite-<small>¹³</small>C-glucuronic acid coprecipitate (<small>⁵⁷</small>Fh<small>¹³</small>GluC), or only dissolved glucuronic acid (<small>¹³</small>GluC<small>_aq</small>) were added. By tracking the transformation of the <small>⁵⁷</small>Fe-ferrihydrite in the solid phase with Mössbauer spectroscopy together with analysis of the iron isotope composition of the aqueous phase and chemical extractions with inductively coupled plasma-mass spectrometry, we show that the pure <small>⁵⁷</small>Fe-ferrihydrite underwent more reductive dissolution and transformation than the coprecipitated <small>⁵⁷</small>Fe-ferrihydrite when identical amounts of glucuronic acid were provided (<small>⁵⁷</small>Fh + GluC<small>_aq</small><em>versus</em><small>⁵⁷</small>Fh<small>¹³</small>GluC treatments). In the absence of glucuronic acid, the pure <small>⁵⁷</small>Fe-ferrihydrite underwent the least reductive dissolution and transformation (<small>⁵⁷</small>Fh). Comparing all treatments, the overall extent of Fe(<small>III</small>) reduction, including the added and native Fe minerals, determined with X-ray absorption spectroscopy, was highest in the <small>⁵⁷</small>Fh + GluC<small>_aq</small> treatment. Collectively, our results suggest that the limited bioavailability of the coprecipitated OC restricts not only the reductive dissolution of the coprecipitated mineral, but it also limits the enhanced reduction of native soil Fe(<small>III</small>) minerals.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 9","pages":" 1489-1502"},"PeriodicalIF":4.3,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/em/d4em00238e?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141755710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}