Environmental Research最新文献

{"title":"The Impact of Metal Exposure, Vaginal Microbiota, and Their Interactions on Fertility: A Prospective Cohort Study.","authors":"Xiang Hong, Hanyue Zheng, Mengjie Zhao, Xiaoling Ding, Jiechen Yin, Xuening Zhang, Bei Wang","doi":"10.1016/j.envres.2025.122729","DOIUrl":"https://doi.org/10.1016/j.envres.2025.122729","url":null,"abstract":"<p><p>To explore the effects of metal exposure, vaginal microbiota, and their interactions on time to pregnancy (TTP). A total of 200 couples were recruited in Nanjing. Ultimately, 150 women from whom prepregnancy blood samples and vaginal swabs were collected by trained clinicians were included. After one year of follow-up, the participants were categorized into a pregnant group (n=100) and a non-pregnant group (n=50). Vaginal microbiota were analyzed using 16S rRNA sequencing to examine the microbiota structure, while blood samples were analyzed for concentrations of 22 metal elements using inductively coupled plasma-Mass Spectrometry. The associations between metal exposure, vaginal microbiota, and TTP were analyzed using Cox regression, random forest, and Bayesian kernel machine regression (BKMR). A significant difference in β-diversity of prepregnancy vaginal microbiota was observed between the pregnant and non-pregnant groups (PERMANOVA test P<0.001). In the pregnant group, the relative abundance of Lactobacillus was significantly higher, while Gardnerella (P=0.005) and Atopobium (P=0.007) abundances were significantly lower. Random forest modeling confirmed these three genera as key predictors of fertility. Cr, Na, Co, Ni, and Cu were the main metals associated with fertility. Elevated Cr, Cu, and Ni concentrations were linked to reduced fertility in cubic spline analysis. BKMR analysis identified Cu (PIP: 1.0000) as the key factor influencing fertility. Notably, Cu and Cr exhibited the strongest interactions with key bacterial genera, particularly Atopobium, Gardnerella, and Lactobacillus. This study systematically reveal the interaction between metal exposure and vaginal microbiota in relation to female fertility, offering new insights into reproductive health risks.</p>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":" ","pages":"122729"},"PeriodicalIF":7.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144991156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Excellent adsorption performance of sulfated yeast for heavy metal ions: High capacity and selectivity for rare earth elements","authors":"Kokoro Yamada,&nbsp;Moena Amano,&nbsp;Yoshihiro Ojima,&nbsp;Hideki Azuma,&nbsp;Koichi Igarashi,&nbsp;Masayuki Azuma","doi":"10.1016/j.envres.2025.122743","DOIUrl":"10.1016/j.envres.2025.122743","url":null,"abstract":"<div><div>The aim of this study is to provide valuable knowledge for developing a biological material effective in recovering and removing metals from solutions. Yeast was used as the base material. Yeast, a homogeneous material with a rigid cell wall, is inexpensive, readily available (it can even be obtained from brewer's waste), and amenable to chemical and genetic modification. Since native yeast exhibits low adsorption capacity, yeast with numerous sulfate groups to enhance metal binding was prepared through chemical modification in this study, and the heavy metal adsorption properties of the resulting S-yeast were analyzed. The modification increased the sulfur content of the yeast to over 10 %, and S-yeast prepared using H₃NSO₃ exhibited a high adsorption capacity exceeding 2 mmol/g dry weight for Cu, Zn, and Cd. Additionally, Cu was rapidly adsorbed upon addition, could be desorbed with HCl, and readsorbed onto the desorbed yeast. Rare earth elements were also adsorbed at levels exceeding 1 mmol/g dry weight, with these values surpassing those achieved by previously developed phosphorylated yeast. The effect of HCl addition on adsorption differed between rare earth elements and divalent heavy metals, with rare earths selectively adsorbed at 0.3 M HCl. Furthermore, light rare earth elements were selectively adsorbed over heavy rare earths, suggesting that rare earths with larger ionic radii are more readily adsorbed. Sulfated yeast thus shows promise as a material for removing and recovering heavy metals from solution. These findings offer valuable insights into the development of new environmental materials.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"286 ","pages":"Article 122743"},"PeriodicalIF":7.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144991104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Retention of increased maximum oxyregulation capacity in corals transplanted from an extreme mangrove environment to a reef flat","authors":"Nicole J. Dilernia ,&nbsp;David J. Suggett ,&nbsp;Christine D. Roper ,&nbsp;Rachel Alderdice ,&nbsp;Christian R. Voolstra ,&nbsp;Michael Kühl ,&nbsp;Emma F. Camp","doi":"10.1016/j.envres.2025.122740","DOIUrl":"10.1016/j.envres.2025.122740","url":null,"abstract":"<div><div>Loss of oxygen (O₂) from the world's oceans to physiologically-critical levels (“hypoxia”) is an important, yet understudied stressor for coral reefs. However, extreme reef-neighbouring ecosystems such as mangrove lagoons that are routinely subjected to frequent low-<em>p</em>O₂ exposure (i.e., low partial pressure of O₂), high temperature fluctuations, and low-pH, may be harbouring corals with a higher capacity for oxyregulation, rendering them more resilient to adapt to life in low-<em>p</em>O₂ surroundings. We investigated differences in the hypoxic response of the common reef-building coral <em>Pocillopora acuta</em> following 1-year transplantation between Low Isles reef flat (a comparatively more stable O₂ environment) and Woody Island mangrove lagoon (a more variable and oftentimes low-<em>p</em>O₂ habitat), on the Great Barrier Reef. Analysing hypoxia response curves and metabolic function and physiology, we found that mangrove <em>P. acuta</em> retained attributes for hypoxic tolerance when transferred between habitats. These corals survived frequent low-<em>p</em>O₂ exposure (&lt;1.77 mg O₂ L⁻¹), and although total positive regulation (T_pos) was similar between all coral populations, mangrove-to-reef transplants exerted their maximum regulation capacity (P_cmax) at a lower <em>p</em>O₂ than all other groups, even after 1-year in a more typical O₂ environment. Gene expression analyses also revealed activation of non-hypoxia inducible factor target pathways in mangrove corals as an alternative means of anaerobic respiration. The ability of coral populations from extreme ecosystems to exert maximum regulation capacity at low-<em>p</em>O₂ may therefore be a long-term conserved property, based on greater O₂ metabolisation, highlighting tolerance of mangrove <em>P. acuta</em> to survive extreme O₂ conditions in this mangrove environment.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"286 ","pages":"Article 122740"},"PeriodicalIF":7.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144933616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Endocrine Disrupting Chemicals and Female Sexual Health: An Emerging Research Priority.","authors":"Julia Bond, Samantha Schildroth, Lauren A Wise","doi":"10.1016/j.envres.2025.122728","DOIUrl":"10.1016/j.envres.2025.122728","url":null,"abstract":"<p><strong>Background: </strong>Female sexual function is important for positive sexual expression, relationship satisfaction, and overall health and wellbeing. Female sexual dysfunction (FSD), which affects ∼40% of premenopausal women, may manifest as issues with sexual desire, arousal, orgasm, or pain during intercourse. The etiology of FSD is multifactorial but remains incompletely characterized, and endocrine disrupting chemicals (EDCs) may play an underappreciated role in its development.</p><p><strong>Objective: </strong>In this commentary, we identify female sexual function as a health outcome of interest for environmental health scientists by providing a high-level overview of the physiological systems underpinning sexual health, describing the hypothesized toxicological effects of EDCs on sexual function, and discussing research needs to advance science in this area.</p><p><strong>Discussion: </strong>Female sexual function is understudied in environmental health research as an important and distinct health endpoint. Limited toxicological and epidemiological evidence suggests that EDCs may influence sexual health given their ability to dysregulate neurological and hormonal processes underlying female sexual function. Focusing future research efforts on EDCs and female sexual function will help to inform clinical practice, policies, and public health interventions with important implications for female sexuality, health, and well-being.</p>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":" ","pages":"122728"},"PeriodicalIF":7.7,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144937691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Intra-day and inter-day variations of methylmercury and inorganic mercury concentrations in breast milk","authors":"Nozomi Tatsuta ,&nbsp;Miyuki Iwai-Shimada ,&nbsp;Kaname Asato ,&nbsp;Kenta Iwai ,&nbsp;Kunihiko Nakai","doi":"10.1016/j.envres.2025.122736","DOIUrl":"10.1016/j.envres.2025.122736","url":null,"abstract":"<div><h3>Background</h3><div>There is little information regarding the concentrations and variability of methylmercury (MeHg) in breast milk. This study examines the variations in the concentrations of total mercury (THg), MeHg, and inorganic mercury (IHg) in breast milk and suggests a method for collecting breast milk samples for MeHg research.</div></div><div><h3>Methods</h3><div>Breast milk samples were obtained from 11 lactating women, 3–5 months after birth. Mercury species in breast milk were measured by high-performance liquid chromatography with inductively coupled plasma mass spectrometry. Breast milk was examined for foremilk and hindmilk, intra-day (morning, afternoon, evening), and inter-day (morning for three consecutive days) variations. The variation in concentration among individuals was measured using the intraclass correlation coefficient (ICC).</div></div><div><h3>Results</h3><div>The mean maternal age was 33.1 years, 45.5 % of children were first children, and 63.6 % were male. The median MeHg in foremilk was 0.18 (0.05–0.55) ng/g and in hindmilk was 0.58 (0.18–1.18) ng/g. The variation between foremilk and hindmilk was significant for MeHg and THg but minor for IHg. Intra- and inter-day variations in mercury were analyzed using ICC, and all concentrations were &gt;0.9, indicating high reliability. MeHg to THg ratios were 66.7 % and 75.9 % in foremilk and hindmilk.</div></div><div><h3>Conclusions</h3><div>This study found variations in THg and MeHg concentrations between foremilk and hindmilk samples. To assess MeHg levels in breast milk, collect both foremilk and hindmilk for analysis. No intra- or inter-day variations were observed for MeHg or IHg. More infant exposure info is useful for precise analysis.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"285 ","pages":"Article 122736"},"PeriodicalIF":7.7,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144932030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"17β-trenbolone increases circulating myeloid-derived MMP8 in CSDS-induced mice and drives depressive tendencies to social threat","authors":"Xiang Zuo ,&nbsp;Xiaochen Kuang ,&nbsp;Ruimin Li ,&nbsp;Yudi Zhao ,&nbsp;Jingyi Tuo ,&nbsp;Jinyu Qiu ,&nbsp;Qili Zhao ,&nbsp;Huijuan Bai ,&nbsp;Xin Zhao ,&nbsp;Xizeng Feng","doi":"10.1016/j.envres.2025.122733","DOIUrl":"10.1016/j.envres.2025.122733","url":null,"abstract":"<div><div>Chronic psychosocial stress is a major risk factor for major depressive disorder (MDD). The impact of 17β-trenbolone (17-TB), an anabolic steroid and potential environmental endocrine disruptor, on stress responses and mood states in mammals is unclear. In this study, we explored how 17-TB interacts with chronic social defeat stress (CSDS) to drive neuroinflammatory cascades and behavioral abnormalities in mice. Utilizing a multidisciplinary cross-cutting approach integrating behavioral analysis, molecular biology, neuroimmunology, and electrophysiology, we ascertained that 17-TB exacerbated CSDS-induced mice peripheral inflammation by increasing IL-6, IL-1β, TNF-α, and myeloid-derived Matrix metalloproteinase 8 (MMP8). Furthermore, the study identified a concomitant downregulation of blood-brain barrier (BBB) tight junction proteins (ZO-1, Occludin), accompanied by an increase in BBB permeability. This led to degradation of the extracellular matrix (ECM) and altered neuronal excitability, evidenced by elevated EPSC amplitude/frequency and abnormal action potential firing, which were linked to heightened anxiety and depressive-like behaviors. Interestingly, 17-TB enhanced social dominance in CSDS-induced mice, associated with increased c-Fos⁺ expression in the medial prefrontal cortex (mPFC), indicating a disconnect between social competitiveness and emotional vulnerability. In conclusion, our study identified 17-TB as a neurotoxin that exacerbates stress-induced depression-like behaviors through BBB leakage, neuroinflammation, and ECM-driven synaptic dysfunction. The paradoxical social dominance highlights the ability of endocrine-disrupting chemicals (EDCs) to dysregulate neural circuits controlling emotional and social behavior. These findings underscore the imperative for a re-evaluation of EDC regulatory policy and the formulation of a therapeutic strategy that targets MMP8, a pivotal mediator of neuro-immune crosstalk in mood disorders.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"285 ","pages":"Article 122733"},"PeriodicalIF":7.7,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144932031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Extracellular vesicle proteomic expression is influenced by mining tenure in former uranium miners","authors":"Mijung Oh ,&nbsp;Eunju Lim ,&nbsp;Onamma Edeh ,&nbsp;Sydnee Yazzie ,&nbsp;Deborah Kanda ,&nbsp;Li Luo ,&nbsp;Quiteria Jacquez ,&nbsp;Ting Jiang ,&nbsp;Prajakta Adsul ,&nbsp;Jason Weick ,&nbsp;Akshay Sood ,&nbsp;Katherine E. Zychowski","doi":"10.1016/j.envres.2025.122737","DOIUrl":"10.1016/j.envres.2025.122737","url":null,"abstract":"<div><h3>Background</h3><div>Chronic exposure to uranium (U) rich environments poses significant health risks, yet the molecular mechanisms underlying these effects remain poorly understood. Extracellular vesicles (EVs) are membrane-bound vesicles that transfer multiple biomolecules between cells and can regulate cellular function.</div></div><div><h3>Objective</h3><div>To determine whether U-mining tenure is associated with specific alterations in serum-derived EV proteomic and plasma cytokine profiles among former U-miners, and to assess the potential of EV-derived proteins as robust biomarkers of chronic U-exposure relative to canonical cytokines.</div></div><div><h3>Methods</h3><div>Serum and plasma samples were obtained from 39 former U-miners. Small and large EVs were isolated via differential ultracentrifugation and characterized by nanoparticle tracking and western blotting. EV proteomic profiles were analyzed using liquid chromatography-tandem mass spectrometry. Plasma cytokines were quantified using multiplex immunoassays. Age-adjusted linear regression was used to assess associations with mining tenure, and pathway enrichment analysis was performed on significant EV proteins.</div></div><div><h3>Results</h3><div>Eight small-EV and four large-EV proteins significantly correlated with mining tenure after age adjustment. Notably, Complement C1r subcomponent and Vitamin K-dependent protein S, and Fibrinogen alpha chain exhibited strong inverse correlations. Enrichment analyses highlighted immune-related and extracellular matrix pathways. Six cytokines were initially associated with mining tenure but lost significance after age adjustment. In contrast, EV protein associations appeared more robust for this confounding, underscoring their potential as exposure biomarkers.</div></div><div><h3>Conclusions</h3><div>Serum EV-derived protein signatures were nominally associated with U-mining tenure independent of age, whereas cytokine profiles were confounded by age. These findings suggest that EV-derived proteins may provide sensitive biomarkers for monitoring long-term health effects of U-exposure, which warrants further investigation in larger cohorts.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"286 ","pages":"Article 122737"},"PeriodicalIF":7.7,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144937637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Interaction between airway inflammation and gut microbiota dysbiosis caused by high temperatures (40 °C) and traffic-PM2.5 in mouse model","authors":"Linjing Deng ,&nbsp;Ao Wang ,&nbsp;Ping Ma ,&nbsp;Yang Wu ,&nbsp;Fang Zhu ,&nbsp;Daolin Du ,&nbsp;Charles Obinwanne Okoye ,&nbsp;Xunfeng Chen ,&nbsp;Qihong Deng","doi":"10.1016/j.envres.2025.122731","DOIUrl":"10.1016/j.envres.2025.122731","url":null,"abstract":"<div><div>Though epidemiological studies have shown that high temperatures and traffic-PM_2.5 alone can increase the risk of asthma, there were not clear about their associated impact on asthma. This study investigated the combination effect of high temperatures (40 °C) and traffic-PM_2.5 on asthma and molecular mechanism. BALB/c mice were treated with high temperature and traffic-PM_2.5. Firstly, airway hyperresponsiveness (AHR) was measured <em>in vivo</em> before lung histological analysis. The inflammation biomarkers of asthma were further analyzed to examine the role of oxidative stress, and TRPV1 and gut microbiota. Finally, we investigated whether vitamin E (Ve) and capsazepine (Czp) could protect against airway inflammation. Serum proteins, lung tissue cytokines, and proinflammatory factors with the high temperatures and traffic-PM_2.5 treatment were markedly higher than those in the control groups. AHR indicated that lung function decreased after high temperatures and traffic-PM_2.5 exposure. The lung histological assay demonstrated changes of airway. Our results showed that 40 °C and traffic-PM_2.5 could aggravate airway inflammation, mainly through activation of oxidative stress and TRPV1. High temperature could change gut microbial community structure of asthma mice. Moreover, imbalance of Th1/Th2 exacerbated gut microbiota dysbiosis under high temperature. Hence, this study clarified asthma airway inflammation aggravated by environmental factors from the perspective of gut-lung axes providing novel theoretical basis for the treatment of asthma.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"285 ","pages":"Article 122731"},"PeriodicalIF":7.7,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144937714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Sustainable rice husk ash-tannin xerogel for ciprofloxacin removal from water","authors":"Yaksha Verma ,&nbsp;Pooja Dhiman ,&nbsp;Amit Kumar ,&nbsp;Tongtong Wang ,&nbsp;Gaurav Sharma","doi":"10.1016/j.envres.2025.122701","DOIUrl":"10.1016/j.envres.2025.122701","url":null,"abstract":"<div><div>This research investigates the synthesis and application of a bioderived xerogel (BDX) synthesized from rice husk and tannins to eliminate Ciprofloxacin (CIP) from water-based media. Xerogel was prepared via sol-gel method, incorporating rice husk ash and tannin extract, along with polyvinyl alcohol (PVA) as a binding agent. Characterization techniques including, FTIR (Fourier Transform Infrared Spectroscopy), XRD (X-ray Diffraction), SEM (Scanning Electron Microscopy), AFM (Atomic Force Microscopy), TGA (Thermogravimetric Analysis), and BET (Brunauer-Emmett-Teller) surface area analysis were employed to evaluate its structural and chemical properties. Adsorption capacity of the xerogel was assessed through batch experiments under various conditions of temperature, pH, adsorbent-dosage, and initial-CIP concentration. Results indicate that bio-derived xerogel exhibits promising adsorption properties for CIP, with maximum efficiency observed under acidic conditions and at higher temperatures. The adsorption isotherm and kinetic studies further confirm the applicability of the Langmuir isotherm and pseudo-first-order kinetics model, respectively, suggesting adsorption is mono-layer with physisorption as the rate-limiting step. Moreover, regeneration studies demonstrate the potential for reusability, supporting its practical application for environmental remediation applications.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"286 ","pages":"Article 122701"},"PeriodicalIF":7.7,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144937732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Thermodynamic regulation of aerosol pH by temperature and humidity: The role of gas-particle partitioning of semi-volatile inorganic species in a subtropical region","authors":"Jun Tao ,&nbsp;Yunfei Wu ,&nbsp;Yong Deng ,&nbsp;Bangkai Hu ,&nbsp;Zhen Zhou","doi":"10.1016/j.envres.2025.122727","DOIUrl":"10.1016/j.envres.2025.122727","url":null,"abstract":"<div><div>Aerosol acidity (pH) plays a critical role in atmospheric chemical processes, secondary aerosol formation, and urban air quality. Based on five years of hourly observations (2019–2023) in subtropical Dongguan, this study investigates the variability and thermodynamic regulation of aerosol pH, with a focus on aerosol liquid water content (ALWC), hydrogen ion (H⁺) concentrations, and their interactions. Secondary inorganic aerosols (SIA), including NH₄⁺, SO₄²⁻, NO₃⁻ and Cl⁻, accounted for 92 ± 4 % of total water-soluble inorganic ions (WSIIs), with sufficient total NH₃ (TNH₃) and non-volatile cations (NVCs) available to neutralize acidic species. Nevertheless, aerosol pH remained persistently acidic (2.43–2.77). Compared with 2019, aerosol pH declined slightly during and after the COVID-19 pandemic despite substantial reductions in WSIIs, primarily due to a marked decrease in ALWC (∼40 %) together with a moderate increase in H⁺ (∼20 %). Mechanistically, aerosol pH was jointly regulated by ALWC and H⁺, both influenced by the thermodynamic gas–particle partitioning of semi-volatile species. Warm, dry conditions suppressed ALWC and elevated H⁺, lowering pH, whereas cooler, humid conditions sustained higher ALWC and lower H⁺, raising pH. Thermodynamic simulations with fixed mean compositions further showed that the effects of temperature and relative humidity (RH) on aerosol pH were mediated by the gas–particle partitioning of ammonia. Specifically, the pH response was minimized when NH₄⁺(aq)/TNH₃ was ∼0.2–0.3, corresponding to the strongest buffering capacity, whereas ratios below ∼0.2 produced gas-dominated regimes highly sensitive to temperature, and ratios above ∼0.3 yielded aqueous-dominated regimes more sensitive to RH. These findings provide a robust observational constraint for predicting aerosol acidity and its meteorological dependence, offering new guidance for air-quality management in subtropical regions.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"286 ","pages":"Article 122727"},"PeriodicalIF":7.7,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144937741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}