Environment International最新文献

{"title":"Interaction between 6PPD/6PPD-Q and natural Fe-Mn nodules: Performance and mechanism of adsorption and oxidative transformation","authors":"Jiaqi Shi, Yan Li, Qi Wei, Xin Zhu, Shaohua Cao, Wenyi Xie, Yang Guo, Jing Wei, Zekai Li, Tao Long","doi":"10.1016/j.envint.2025.109438","DOIUrl":"https://doi.org/10.1016/j.envint.2025.109438","url":null,"abstract":"The widely used rubber antioxidant N-(1,3-Dimethylbutyl)-N’-phenyl-p-phenylenediamine (6PPD) and its ozonated product, 6PPD-quinone (6PPD-Q), are highly toxic to aquatic life, yet understanding on their environmental behaviors is limited. This study comprehensively investigated their adsorption and transformation processes on natural Fe-Mn nodules (NFMN), which commonly exist in sediments and soils through a combination of diverse experimental and computational methods. The maximum adsorption capacity of 6PPD-Q (719.2 μg·g⁻¹) is significantly higher than that of 6PPD (133.8 μg·g⁻¹) at 293 K, and it is more difficult to desorb. They follow different kinetic and isothermal adsorption models, and environmental conditions (including temperature, pH, and anions) exert distinct influences on the adsorption of the two substances. Adsorption mechanisms involving electrostatic attraction, charge transfer, hydrogen bonding, and Lewis acid-base complexation were unveiled. For 6PPD, electrostatic adsorption and Lewis acid-base complexation contribute significantly to its adsorption. Conversely, for 6PPD-Q, the contribution of Lewis acid-base complexation outweighs that of hydrogen bonding, while the effect of electrostatic adsorption is relatively negligible. The stronger electrostatic attraction, more efficient charge transfer, and a greater number of binding sites for hydrogen bonding and Lewis acid-base complexation with NFMN results in more robust adsorption of 6PPD-Q. Furthermore, 6PPD can transform into 6PPD-Q on NFMN, facilitated by dissolved Mn(III). This study advances understanding of the adsorption behavior and mechanism of 6PPD and 6PPD-Q, and highlights a new pathway for 6PPD-Q formation, which provides valuable reference for assessing the water body exposure risks and formulating environmental remediation strategies for such pollutants.<h3>Environmental Implication</h3>This study offers the first comprehensive insight into the interactions between 6PPD/6PPD-Q and NFMN, illuminating their environmental behavior in water and soil systems. It reveals the adsorption discrepancy between 6PPD and 6PPD-Q, and elucidates the mechanisms underlying the difference in adsorption. Additionally, it uncovers a novel pathway for 6PPD-Q formation, offering valuable implications for risk assessment and environmental remediation strategies.","PeriodicalId":308,"journal":{"name":"Environment International","volume":"6 1","pages":""},"PeriodicalIF":11.8,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143782924","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":"Dynamic assessment of phthalate exposure: Linking internal and external monitoring in diverse indoor environments","authors":"Xiaojun Zhou, Wenlong Li, Runjie Li, Haoyu Dang, Xinke Wang","doi":"10.1016/j.envint.2025.109423","DOIUrl":"https://doi.org/10.1016/j.envint.2025.109423","url":null,"abstract":"Phthalates (PAEs), as prevalent endocrine disruptors, are widely distributed in indoor environments and enter the human body through dermal contact, respiratory inhalation, and ingestion, subsequently participating in metabolic processes across various organs and tissues. Existing studies primarily focus on predicting regional exposure scenarios to assess internal or external exposures risks; however, limited studies have systematically examined the correlation and discrepancies between internal and external exposures. This study collected PAEs samples from three phases (gas, particle, and dust phases) across three representative indoor environments and conducted urinary biomonitoring of phthalate metabolites (mPAEs) among exposed populations. Results showed that PAEs concentrations in the gas phase (21.67 μg·m⁻³) and particle phase (2.38 μg·m⁻³) were significantly higher in laboratories than in dormitories and offices, whereas office desktops exhibited the highest dust phase concentration (312 μg·g⁻¹). Urinary analysis revealed distinct metabolic profiles across populations: MBP was the dominant metabolite in office and dormitory groups (median: 19.3 ng·mL⁻¹ and 10.4 ng·mL⁻¹, respectively), while MMP prevailed in laboratory populations (median: 18.3 ng·mL⁻¹). Seasonal variation analysis indicated that urinary mPAEs concentrations were 4.28 times higher in summer than in winter. Demographic analysis showed that mPAEs levels were higher in males, individuals with obesity, and those with frequent plastic use compared to females, individuals with normal BMI, and those with infrequent plastic use. Furthermore, external exposure estimated from ambient PAEs concentrations exceeded internal exposure derived from urinary mPAEs concentrations by 17.3 %. These findings provide critical insights into exposure pathway differentiation and risk assessment optimization for indoor PAEs contamination.","PeriodicalId":308,"journal":{"name":"Environment International","volume":"38 1","pages":""},"PeriodicalIF":11.8,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143766454","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":"Microplastics and nanoplastics co-exposure modulates chromium bioaccumulation and physiological responses in rats","authors":"Damir Suljević ,&nbsp;Patrik Karlsson ,&nbsp;Muhamed Fočak ,&nbsp;Maja Mitrašinović Brulić ,&nbsp;Jasmina Sulejmanović ,&nbsp;Elma Šehović ,&nbsp;Eva Särndahl ,&nbsp;Magnus Engwall ,&nbsp;Andi Alijagic","doi":"10.1016/j.envint.2025.109421","DOIUrl":"10.1016/j.envint.2025.109421","url":null,"abstract":"<div><div>The environmental fragmentation of plastics generates a mixture of plastic particles of various sizes, which frequently co-occur with other mobile and persistent environmental pollutants. Despite the prevalence of such scenarios, the interaction between micro- and nanoplastics (MNPs) and their combined effects with environmental pollutants, such as highly toxic hexavalent chromium (Cr(VI)), remain almost entirely unexplored in mammalian species. This study demonstrated that nanoplastic and microplastic particles co-aggregate and together influence Cr bioaccumulation patterns and related physiological alterations in rats. Following a four-week repeated intragastric exposure of Wistar rats to MNPs and Cr(VI), either alone or in combination, MNPs significantly enhanced Cr bioaccumulation in the liver, heart, brain, and skin. Under co-exposure conditions, Cr(VI) was the primary driver of cellular effects observed in the blood, including shifts in immune cell subpopulations (e.g., neutrophils, lymphocytes) and alterations in red blood cell indices, while serum biochemistry reflected limited physiological stress. MNPs <em>per se</em> decreased creatine kinase activity and increased cholesterol levels. In summary, polystyrene MNPs increase Cr(VI) distribution and bioavailability, but co-exposure does not uniformly exacerbate toxicity. Instead, their interaction may selectively alter physiological responses, emphasizing the need for a deeper understanding of their combined effects and potential health risks.</div></div>","PeriodicalId":308,"journal":{"name":"Environment International","volume":"198 ","pages":"Article 109421"},"PeriodicalIF":10.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143736359","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}

{"title":"A novel data-driven screening method of antidepressants stability in wastewater and the guidance of environmental regulations","authors":"Peixuan Sun ,&nbsp;Huaishi Liu ,&nbsp;Yuanyuan Zhao ,&nbsp;Ning Hao ,&nbsp;Zhengyang Deng ,&nbsp;Wenjin Zhao","doi":"10.1016/j.envint.2025.109427","DOIUrl":"10.1016/j.envint.2025.109427","url":null,"abstract":"<div><div>Wastewater-based epidemiology (WBE) represents a powerful technique for quantifying the attenuation characteristics and consumption of pharmaceuticals. In addition to WBE, no further methods have been developed to assess the wastewater stability related to antidepressants (ADs). In this study, the biodegradability, solubility, and adsorption or partition of 66 ADs were objectively scored according to the relevant guidelines of the Organisation for Economic Cooperation and Development. An assessment framework and the MSSL-RealFormer classification model of ADs wastewater stability were constructed based on physicochemical properties to predict the ADs wastewater stability and the quantitative structure–activity relationship. The constructed MSSL-RealFormer classification model exhibited a markedly higher prediction accuracy than traditional methods. Furthermore, 15 high-stable ADs in wastewater with low biodegradability, high solubility, and low adsorption or partition were identified. SHapley Additive exPlanation method demonstrated that group hydrophobicity, electrostatic and van der Waals forces exerted a significant influence on the ADs wastewater stability. And molecular stability was found to be significantly correlated with the ADs wastewater stability. A combination of density functional theory and MSSL-RealFormer classification model was employed to identify 17 high-stable transformation products of nine medium- and low-stable ADs in wastewater. The Ecological Structure Activity Relationships model demonstrated that bupropion, tapentadol and chlorpheniramine exhibited significant acute toxicity to the aquatic food chain. In this study, a novel deep learning model was constructed to rapidly screen the correlation between the ADs wastewater stability and their molecular structures. It is anticipated to prove a favorable tool for optimizing the wastewater stability screening of pharmaceuticals.</div></div>","PeriodicalId":308,"journal":{"name":"Environment International","volume":"198 ","pages":"Article 109427"},"PeriodicalIF":10.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143737162","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}

{"title":"Plastic chemicals disrupt molecular circadian rhythms via adenosine 1 receptor in vitro","authors":"Molly McPartland,&nbsp;Felicity Ashcroft,&nbsp;Martin Wagner","doi":"10.1016/j.envint.2025.109422","DOIUrl":"10.1016/j.envint.2025.109422","url":null,"abstract":"<div><div>The adenosine 1 receptor (A₁R) is a G protein-coupled receptor that transduces signals to regulate sleep-wake cycles and circadian rhythms. Plastic products contain thousands of chemicals, known to disrupt physiological function. Recent research has demonstrated that some of these chemicals are also A₁R agonists, however, the extent to which such activation propagates downstream and results in cellular alterations remains unknown. Thus, we investigate whether chemicals extracted from polyurethane (PUR) and polyvinyl chloride (PVC) plastics disrupt circadian rhythms via agonism of A₁R. We confirm that plastic chemicals in both plastics activate A₁R and inhibit intracellular cAMP in U2OS cells. Notably, this inhibition is comparable to that induced by the highly specific A₁R agonist 2′-MeCCPA. To assess circadian disruption, we quantify temporal expression patterns of the clock genes PER2 and CRY2 at 4-h intervals over 48 h. Here, exposure to plastic chemicals shifts the phase in the oscillatory expression cycles of both clock genes by 9–17 min. Importantly, these effects are dose-dependent and reversible when A₁R is inhibited by a pharmacological antagonist. This demonstrates that plastic chemicals can disrupt circadian processes by interfering with A₁R signaling and suggests a novel mechanism by which these and other chemicals may contribute to non-communicable diseases.</div></div>","PeriodicalId":308,"journal":{"name":"Environment International","volume":"198 ","pages":"Article 109422"},"PeriodicalIF":10.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143745388","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}

{"title":"Quanta emission rate during speaking and coughing mediated by indoor temperature and humidity","authors":"Vitor Lavor ,&nbsp;Jianjian Wei ,&nbsp;Omduth Coceal ,&nbsp;Sue Grimmond ,&nbsp;Zhiwen Luo","doi":"10.1016/j.envint.2025.109379","DOIUrl":"10.1016/j.envint.2025.109379","url":null,"abstract":"<div><div>In epidemiological prospective modelling, assessing the hypothetical infectious quanta emission rate (<em>E_q</em>) is critical for estimating airborne infection risk. Existing <em>E_q</em> models overlook environmental factors such as indoor relative humidity (RH) and temperature (T), despite their importance to droplet evaporation dynamics. Here we include these environmental factors in a prospective <em>E_q</em> model based on the airborne probability functions with emitted droplet distribution for speaking and coughing activities. Our results show relative humidity and temperature have substantial influence on <em>E_q</em>. Drier environments exhibit a notable increase in suspended droplets (cf. moist environments), with <em>E_q</em> having a 10-fold increase when RH decreases from 90 % to 20 % for coughing and a 2-fold increase for speaking at a representative summer indoor environment (T = 25° C). In warmer environments, <em>E_q</em> values are consistently higher (cf. colder), with increases of up to 22 % for coughing and 9 % for speaking. This indicates temperature has a smaller impact than humidity. We demonstrate that indoor environmental conditions are important when quantifying the quanta emission rate using a prospective method. This is essential for assessing airborne infection risk.</div></div>","PeriodicalId":308,"journal":{"name":"Environment International","volume":"198 ","pages":"Article 109379"},"PeriodicalIF":10.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143627766","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}

{"title":"Metal bioaccessibility in size-resolved atmospheric particles: Source and aging impacts","authors":"Kun Hua ,&nbsp;Rui Chen ,&nbsp;Bohan Zhang ,&nbsp;Yingze Tian ,&nbsp;Yinchang Feng","doi":"10.1016/j.envint.2025.109425","DOIUrl":"10.1016/j.envint.2025.109425","url":null,"abstract":"<div><div>Metal bioaccessibility is critical for health effects. The influence of sources and aging processes on bioaccessibility of metals in size-resolved atmospheric particulate matter (PM) remains unclear. Size-resolved bioaccessibility of metals in source-emitted and atmospheric PM was measured in this study. The bioaccessibility of most metals varied greatly with sources, while it remained relatively stable across different sizes for each source. In atmospheric PM, Cu, Mn, Cr, and V showed high bioaccessibility at fine size but low at coarse size especially in floating dust season, indicating effects of combustion sources at fine size and dust sources at coarse size. Atmospheric As and Pb bioaccessibility showed slight size variability and were lower during heating season, linking with enhanced coal combustion with relatively low bioaccessibility. An advanced method was developed to quantify source-specific risk based on size-resolved bioaccessibility. Percentage contributions to cancer risk (CR) of PM₁₀ were the highest for industrial source (IS, 38 %), followed by aged aerosol (AA, 22 %), and coal combustion (CC, 18 %). Contribution of IS was high at sizes &lt; 0.43 µm; and that of CC was high at sizes &lt; 0.43 µm and 1.1–4.7 µm. Additionally, explainable machine learning revealed that atmospheric processes enhanced the Mn bioaccessibility, likely due to highly soluble MnSO₄ formed through acid-processing; and increased the Cr bioaccessibility, probably due to increased fractions of hexavalent Cr originating from oxidation processes.</div></div>","PeriodicalId":308,"journal":{"name":"Environment International","volume":"198 ","pages":"Article 109425"},"PeriodicalIF":10.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143736462","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}

{"title":"Percutaneous penetration of typical Organophosphate esters under catalysis by Carboxylesterase: Characteristics, mechanism and prediction model","authors":"Yan Yang ,&nbsp;Yuwan Hou ,&nbsp;Yonglong Liao ,&nbsp;Zeji Huang ,&nbsp;Jiejie Pan ,&nbsp;Xin Yang ,&nbsp;Haojia Chen ,&nbsp;Zenghua Qi","doi":"10.1016/j.envint.2025.109419","DOIUrl":"10.1016/j.envint.2025.109419","url":null,"abstract":"<div><div>Although the relationship between organophosphate esters (OPEs) percutaneous penetration and their specific physicochemical properties has been investigated, little information is available regarding the percutaneous penetration of OPEs under the interaction of skin enzymes. Herein, we used an <em>in vitro</em> skin model to quantitatively assess the skin permeation of six typical OPEs. The <em>in vitro</em> results demonstrated that 0.34–49.87% of OPEs and 0.80–2.95% of their metabolites (mOPEs) penetrated the skin. Notably, triphenyl phosphate (TPHP) and tri-3-cresyl phosphate (TCRP), which exhibit high lipophilicity and large molecular weights, were more likely to be deposited in the skin tissue, thereby hindering their penetration into the body. However, the concentrations of their metabolites, diphenyl hydrogen phosphate (DPHP) and bis(2-methylphenoxy) phosphinic acid (DCRP), in the receptor fluid were approximately six times higher than those of their parent compounds. After <em>in vivo</em> dermal OPE exposure, all parent OPEs were detected in both the stratum corneum and viable tissue (VT). Proteomic analysis and enzymatic hydrolysis experiments revealed that the percutaneous biotransformation of OPEs in VT is mediated primarily by carboxylesterase (CES). A biomimetic bilayer skin membrane based on the CES level in fresh skin yielded results closer to the real skin absorption data of OPEs than prior models. Thus, a more accurate prediction model was established to assess the percutaneous penetration of OPEs. Our results provide valuable insights into the skin absorption of OPEs and emphasize the role of skin CES in calculating and predicting the percutaneous penetration of OPEs.</div></div>","PeriodicalId":308,"journal":{"name":"Environment International","volume":"198 ","pages":"Article 109419"},"PeriodicalIF":10.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143736429","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}

{"title":"Quantification of greenhouse gas emissions from a municipal solid waste incinerator using an uncrewed aerial vehicle","authors":"Keun Taek Kim ,&nbsp;Horim Kim ,&nbsp;Sangjae Jeong ,&nbsp;Young Su Lee ,&nbsp;Eunhwa Choi ,&nbsp;Jae Young Kim","doi":"10.1016/j.envint.2025.109396","DOIUrl":"10.1016/j.envint.2025.109396","url":null,"abstract":"<div><div>The accurate quantification of greenhouse gas emissions from waste treatment facilities is critical for effective climate change mitigation and regulatory compliance. Measurement-based methods are increasingly emphasized as essential for addressing uncertainties in emission estimates, with uncrewed aerial vehicles (UAVs) recognized for their flexibility and ability to capture spatially resolved data. This study evaluated CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> emissions at a municipal solid waste incinerator using UAV monitoring with two quantification methods—the mass balance and inverse Gaussian methods. Ground-based wind data introduced significant uncertainty in CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> emission quantification. Therefore, this study proposed using a mounted anemometer to capture high-resolution spatially-resolved wind data. The performance of the proposed quantification methods was assessed by comparing UAV-derived fluxes to reference quantification data to calculate errors, which were then compared across methods to evaluate accuracy. The mass balance method, incorporating spatially-resolved wind data, achieved a mean absolute percentage error (MAPE) of 37.34%, which was a marked improvement compared to the 64.32% MAPE using spatially-averaged wind data. Similarly, the inverse Gaussian method showed a lower MAPE of 46.45% using spatially-resolved wind data, compared to 54.97% using spatially averaged wind data. Additionally, the advantages of each method under varying conditions of wind variability were evaluated. This study demonstrates that spatially-resolved wind measurements with a mounted anemometer improve the accuracy of CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> emission calculations. This approach highlights the importance of UAV-based monitoring of greenhouse gases emitted by waste management facilities.</div></div>","PeriodicalId":308,"journal":{"name":"Environment International","volume":"198 ","pages":"Article 109396"},"PeriodicalIF":10.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143713214","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}

{"title":"Single-cell analysis reveals antibiotic affects conjugative transfer by modulating bacterial growth rather than conjugation efficiency","authors":"Li Liu ,&nbsp;Qiang-hong Zhang ,&nbsp;Meng-zi Li ,&nbsp;Rui-tong Li ,&nbsp;Zhiming He ,&nbsp;Arnaud Dechesne ,&nbsp;Barth F. Smets ,&nbsp;Guo-ping. Sheng","doi":"10.1016/j.envint.2025.109385","DOIUrl":"10.1016/j.envint.2025.109385","url":null,"abstract":"<div><div>Antibiotic resistance genes (ARGs) pose a significant threat to human health and the environment. Quantifying the efficiency of horizontal gene transfer (HGT) is challenging due to diverse biological and environmental influences. Single-cell level approaches are well-suited for investigating conjugative transfer, given its reliance on cell-to-cell contact nature and its capacity to offer insights into population-level responses. This study introduces a self-developed system for automated time-lapse image acquisition and analysis. Using a custom dual-chamber microfluidic chip and Python-based image analysis pipeline, we dynamically quantify the ARGs conjugation efficiency at single-cell level. By combining experiments with individual-based modelling, we isolate the effects of subinhibitory antibiotic concentrations on conjugation efficiency from those related to bacterial growth dynamics. No significant variation in <em>Escherichia coli</em> conjugation efficiency was observed across kanamycin concentrations (0 to 50 mg l⁻¹). Moreover, recipient cells with higher growth rates show a greater propensity for plasmid acquisition, suggesting the physiological state of cells pre-conjugation influences their susceptibility to gene transfer. Our methodology eliminates population growth bias, revealing the intrinsic nature of conjugation efficiency. This approach advances our understanding of the factors influencing HGT efficiency and holds promise for studying other microbial interactions.</div></div><div><h3>Synopsis</h3><div>This study employs single-cell analysis to reveal that subinhibitory concentrations of antibiotics affect the conjugative transfer of antibiotic resistance genes by modulating bacterial growth rate rather than conjugation efficiency.</div></div>","PeriodicalId":308,"journal":{"name":"Environment International","volume":"198 ","pages":"Article 109385"},"PeriodicalIF":10.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758219","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}