Environmental Pollution最新文献

{"title":"On-road measurement of post-catalyst ammonia emissions from gasoline and hybrid vehicles using quantum cascade laser detector","authors":"Ruonan Li ,&nbsp;Chongyao Wang ,&nbsp;Xin Wang ,&nbsp;Jiaxin Luo ,&nbsp;Dailin Yin ,&nbsp;Miao Wen ,&nbsp;Lijun Hao ,&nbsp;Jianwei Tan ,&nbsp;Yunshan Ge","doi":"10.1016/j.envpol.2024.125319","DOIUrl":"10.1016/j.envpol.2024.125319","url":null,"abstract":"<div><div>Ammonia emissions from gasoline vehicles have been confirmed an essential precursor of urban secondary aerosols. To more comprehensively understand the formation mechanisms and better control vehicle-related ammonia, this paper measured the on-road ammonia emissions from six conventional and four hybrid vehicles using a state-of-the-art Quantum Cascade Laser analyzer on urban, rural, and highway routes. The test vehicles emitted 0.01–4.27 mg/km of ammonia emissions, with a fleet average of 1.04 mg/km. Compared to the previous laboratory tests, the results of this study were low because of the high emission standards of the vehicles and the near-zero emissions during rural driving. Most test vehicles showed high ammonia emissions during engine warm-up, while some vehicles also had ammonia peaks during dynamic highway driving. On average, hybrid vehicles emitted 60.7% less ammonia emissions than the conventional candidates. It is confirmed that ammonia was formed when incomplete oxidation products presented on a warm catalyst. Engine warm-up, dynamic highway driving, particulate filter regeneration, and hybrid engine re-starting could be important sources. It is hypothesized that the ammonia formed on the upstream catalyst could be consumed by the downstream catalyst at moderate catalyst temperature, resulting in the near-zero ammonia emissions during rural driving.</div></div>","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":"364 ","pages":"Article 125319"},"PeriodicalIF":7.6,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642624","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":"Effect of sulfidogenesis on ferrihydrite geochemistry and associated arsenic fate","authors":"Bowei Zhang, Jiarong Tong, Kun Gao, Chongxuan Liu","doi":"10.1016/j.envpol.2024.125326","DOIUrl":"https://doi.org/10.1016/j.envpol.2024.125326","url":null,"abstract":"The behavior of arsenic (As) in groundwater is closely related to the sulfidation of ferrihydrite. In the ternary ferrihydrite-As-sulfide system, ferrihydrite can either initially adsorb As before sulfide reduction or first encounter sulfide and then interact with the aqueous As, altering As fate. However, their relative contributions to the mineralogical transformation of ferrihydrite and subsequently associated As mobilization/redistribution remain poorly understood. Therefore, batch experiments combined with chemical, microscopic, and spectroscopic analyses were conducted to clarify the geochemistry of ferrihydrite and its influence on As behavior. Results indicated that in the pre-sorption groups, the secondary minerals were predominantly presented in amorphous phase due to the retardative effect of As. At low sulfide concentrations (S/Fe=0.04), the content of residual ferrihydrite was large, which favored As immobilization. At high sulfide concentrations (S/Fe=0.8), however, As was initially released into the solution and subsequently re-immobilized by secondary minerals. The adsorption capacity of the secondary minerals for As decreased with the increase in amorphous mackinawite formation. In the pre-sulfidation groups, rapid ferrihydrite reduction promoted the formation of crystalline minerals, significantly reducing their adsorption capacity. At low sulfide concentrations, the released As was partially adsorbed on the surface of crystalline goethite and lepidocrocite. At high sulfide concentrations, magnetite formed and favored As immobilization through its incorporation into magnetite particles. These results provide important insights into the geochemistry of Fe, S, and As in groundwater systems.","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":"9 1","pages":""},"PeriodicalIF":8.9,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142637801","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":"Skin absorption of metals derived from hydrogenated stainless particles in human skin: Results from the TITANS project.","authors":"Francesca Larese Filon, Giovanna Marussi, Mickael Payet, Olivier Debellemaniere, Pier Camillo Parodi, Nicola Zingaretti, Veronique Malard, Laurence Lebaron-Jacobs, Gianpiero Adami, Marcella Mauro, Elena Pavoni, Matteo Crosera","doi":"10.1016/j.envpol.2024.125327","DOIUrl":"https://doi.org/10.1016/j.envpol.2024.125327","url":null,"abstract":"<p><p>Workers involved in the decommissioning and removal of radioactive material from nuclear power plants can come into contact with tritiated dust from stainless steel. This study aimed to investigate metal penetration and permeation after skin contamination with these particles. Static diffusion Franz cells were used with intact, damaged, or broken human skin. Stainless steel particles 316 L were applied to the donor phases, and the receiving solutions were collected at regular intervals for 24 h to determine the amount of metals that penetrated the skin. The effectiveness of the decontamination procedure was investigated after 30 min using water and soap. The metal content in the skin was evaluated after 24 h of exposure. Metals detected were Ni, Cr, Co, Mn, Cu, Mo. For Ni, Mn, and Cu, we found a significant increase in metal permeation in all treated cells compared with the blank (p < 0.02). For Co and Cr, permeation through the skin was significant only in the decontaminated and broken cells (p < 0.05). Decontaminated skin presented higher metal permeation for Ni, Co and Cu compared to intact skin (p < 0.05) while broken skin presented, as expected, the higher permeation profile (p < 0.05) for all metals. The metal that was more represented inside the skin was Cr, with more than 15 μg/cm² for intact skin. Ni inside the skin reached the 10.2 ± 8.5 μg/cm² for intact skin. Overall, the levels of metals in the receiving solution were very low in the case of intact and damaged skin contact, and the metal levels significantly increased only in the case of broken and decontaminated skin. More relevant appears Skin content with sensitizing metals (Ni, Cr, and Co) that can induce allergic sensitization or cause allergic contact dermatitis in subjects already sensitized.</p>","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":" ","pages":"125327"},"PeriodicalIF":7.6,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142646296","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":"Microplastic fragmentation into nanoplastics by water shear forces during wastewater treatment: mechanical insights and theoretical analysis.","authors":"Sirajum Monira, Rajeev Roychand, Faisal Ibney Hai, Muhammed Bhuiyan, Biplob Kumar Pramanik","doi":"10.1016/j.envpol.2024.125310","DOIUrl":"https://doi.org/10.1016/j.envpol.2024.125310","url":null,"abstract":"<p><p>Nanoplastics (NPs) are generated from the fragmentation of microplastics (MPs) through mechanical forces such as mixing, sonication and homogenization in wastewater treatment plants (WWTPs). Despite their environmental significance, the formation mechanisms and size distribution of NPs in WWTPs are not well understood. This study presents an in-depth investigation into the fragmentation mechanisms of polyethylene (PE) and polystyrene (PS) MPs, sized 250 μm and 106 μm, under simulated WWTP conditions. Our findings demonstrate that under water shear forces ranging from 32 to 100 kJ/L weathered PS and PE particles were further disintegrated into nano-sized particles. Nanoparticle tracking analysis results revealed a significant increase in NP numbers from 8.34 × 10⁸ to 1.54 × 10¹⁰ NPs/mL as the water shear force increased from 32 to 100 kJ/L. Notably, the smallest NP, measuring 54.2 nm, was produced from 106 μm PS particles at 100 kJ/L. Scanning electron microscope images confirmed micro-cracks on the particle surfaces as the dominant fragmentation mechanism. A robust correlation between experimental NP sizes and theoretical predictions underscores the continuous production of NPs during water treatment processes. These results offer groundbreaking insights into the transformation of MPs within WWTPs and underscore the urgent need for effective strategies to mitigate NP pollution.</p>","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":" ","pages":"125310"},"PeriodicalIF":7.6,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142646241","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":"Omics-centric evidences of fipronil biodegradation by Rhodococcus sp. FIP_B3.","authors":"Anjali Jaiswal, Anand Kumar Pandey, Animesh Tripathi, Suresh Kumar Dubey","doi":"10.1016/j.envpol.2024.125320","DOIUrl":"https://doi.org/10.1016/j.envpol.2024.125320","url":null,"abstract":"The widespread use of the pesticide fipronil in domestic and agriculture sectors has resulted in its accumulation across the environment. Its use to assure food security has inadvertently affected soil microbiome composition, fertility and, ultimately, human health. Degradation of residual fipronil present in the environment using specific microbial species is a promising strategy for its removal. The present study delves into the omics approach for fipronil biodegradation using the native bacterium <em>Rhodococcus</em> sp. FIP B3. It has been observed that within 40 days, nearly 84% of the insecticide gets degraded. The biodegradation follows a pseudo-first-order kinetics (k = 0.0197/d with a half-life of ∼11 days). Whole genome analysis revealed Cytochrome P450 monooxygenase, peroxidase-related enzyme, haloalkane dehalogenase, 2-nitropropane dioxygenase, and aconitate hydratase are involved in the degradation process. Fipronil-sulfone, 5-amino-1-(2-chloro-4-(trifluoromethyl)phenyl)-4- ((trifluoromethyl)sulfonyl)-1H-pyrazole-3-carbonitrile, (E)-5-chloro-2-oxo-3- (trifluoromethyl)pent-4-enoic acid, 4,4,4-trifluoro-2-oxobutanoic acid, and 3,3,3- trifluoropropanoic acid were identified as the major metabolites that support the bacterial degradation of fipronil. <em>In-silico</em> molecular docking and molecular dynamic simulation-based analyses of degradation pathway intermediates with their respective enzymes have indicated stable interactions with significant binding energies (-5.9 to -9.7 kcal/mol). These results have provided the mechanistic cause of the elevated potential of <em>Rhodococcus</em> sp. FIP_B3 for fipronil degradation and will be advantageous in framing appropriate strategies for the bioremediation of fipronil-contaminated environment.","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":"17 1","pages":""},"PeriodicalIF":8.9,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642625","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":"Short-chain chlorinated paraffins induce liver injury in mice through mitochondrial disorders and disruption of cholesterol-bile acid pathway","authors":"Xianpeng Zhou, Jiang Wu, Qiang He, Beibei Wang, Xulong Xu, Xue Zhao, Minmin Gao, Biao Yan","doi":"10.1016/j.envpol.2024.125323","DOIUrl":"https://doi.org/10.1016/j.envpol.2024.125323","url":null,"abstract":"Short-chain chlorinated paraffins (SCCPs) are pervasive organic pollutants recognized for their persistence and bio-toxicity. This study investigated the hepatotoxic mechanisms of SCCPs at environmentally relevant concentration (0.7 μg/kg). The results showed that SCCPs exposure in mice resulted in dysregulated blood and liver lipids, marked by elevated cholesterol levels. Additionally, liver function was compromised, as indicated by increased levels of aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase. Histopathological examination of liver tissue post-SCCPs exposure revealed hepatocyte enlargement, vacuolar degeneration, and mild ballooning degeneration. Mechanistically, SCCPs induced mitochondrial abnormalities, evidenced by heightened Hoechst 33258 fluorescence, and augmented reactive oxygen species and malondialdehyde levels in liver tissue. This was accompanied by a reduction in total antioxidant capacity, culminating in elevated apoptosis markers, including cytochrome C and caspase-3. Moreover, SCCPs perturbed hepatocellular energy metabolism, characterized by increased glycolysis, lactic acid, and fatty acid oxidation, alongside a disruption in the tricarboxylic acid cycle and a decline in mitochondrial energy metabolic function. Furthermore, SCCPs exposure downregulated the expression of genes involved in bile acid synthesis (<em>cyp27a1</em>, <em>fxr</em>, and <em>shp</em>), thereby precipitating the cholesterol-bile acid metabolism disorders and cholesterol accumulation. Collectively, these findings underscore that SCCPs, even at environmentally relevant levels, can induce lipid dysregulation, mitochondrial disorders and cholesterol deposition in the hepatocytes, contributing to liver damage. The study’s insights contribute to a comprehension of SCCPs-induced hepatotoxicity and may inform potential preventative and treatment targets for hepatic damage associated with SCCPs exposure.","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":"25 1","pages":""},"PeriodicalIF":8.9,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642623","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":"Adverse outcome pathway of Alzheimer's disease-like changes resulting from autophagy flux blockade after MC-LR exposure","authors":"Yuhan Ma ,&nbsp;Dihui Xu ,&nbsp;Yibin Gan ,&nbsp;Zining Chen ,&nbsp;Yabing Chen ,&nbsp;Xiaodong Han","doi":"10.1016/j.envpol.2024.125322","DOIUrl":"10.1016/j.envpol.2024.125322","url":null,"abstract":"<div><div>Microcystins (MCs) pollution is a worldwide environmental issue concerning about human health. Microcystin-leucine-arginine (MC-LR), the most common type of MCs produced by cyanobacteria, could enter the brain and bring about damage to the nervous system. Up to date, it is not clear about the mechanism of MC-LR-induced neurotoxicity. Amyloid-β (Aβ) deposits are hallmark of Alzheimer's disease (AD). In this study, we revealed that MC-LR exposure at environment-related doses (1, 7.5, 15 μg/L) could promote Aβ accumulation in mouse brain. Mechanically, we firstly found that Aβ accumulation is closely associated with abnormal Aβ degradation due to autophagy flux blockade and lysosome dysfunctions in neurons after MC-LR exposure. Moreover, an adverse outcome pathway (AOP) framework oriented to neurotoxicity of MC-LR was conducted in this study. MC-LR inhibited the activity of protein phosphatase 2A (PP2A) in neurons, which is regarded as a molecular initiating event (MIE). In addition, the abnormalities in autophagy were observed after MC-LR exposure. The hindered autophagosome-lysosome fusion and disrupted lysosomal function were key events (KEs) after MC-LR exposure, which contributed to proteostasis dysregulation, ultimately leading to Aβ abnormal degradation and learning deficits as adverse outcomes (AO) of neurotoxicity. This study provided novel information about MC-LR neurotoxicity and new insights into understanding the mechanisms underlying the environmental chemicals-induced neurodegeneration diseases, which has deep implications for public health.</div></div>","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":"364 ","pages":"Article 125322"},"PeriodicalIF":7.6,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142637802","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":"Characterization of soot and crystalline atmospheric ultrafine particles","authors":"Francisco Berrellez-Reyes ,&nbsp;Benedetto Schiavo ,&nbsp;Belem Gonzalez-Grijalva ,&nbsp;Aracely Angulo-Molina ,&nbsp;Diana Meza-Figueroa","doi":"10.1016/j.envpol.2024.125314","DOIUrl":"10.1016/j.envpol.2024.125314","url":null,"abstract":"<div><div>The extraction and characterization of atmospheric ultrafine particles (UFPs) is critical to understanding environmental health and climate dynamics. This study uses an aqueous extraction method to characterize the size distribution, shape, and composition of atmospheric UFPs. We propose a combined use of techniques rarely implemented in air quality analysis, such as atomic force microscopy (AFM), with more conventional methods, such as Transmission Electron microscopy (TEM) and Dynamic Light Scattering (DLS). DLS results indicate a hydrodynamic diameter range from 117 to 1069 nm and a polydispersity index of 0.3–0.79. The high polydispersity reflects the complexity of UFPs agglomeration processes. AFM identified NPs ranging from 10 to 25 nm; topographic images show soot and crystalline structures. High-resolution TEM analysis measured the interplanar distances of crystalline UFPs, showing the presence of calcium carbonates. TEM-EDS identified soot and crystalline particles with variable composition, from Si-enriched NPs to Ca-F-Cl-Na-Si, carbonates, chlorides, and Zn-Ti-enriched nanosilica. These findings provide valuable insights into the physicochemical properties of atmospheric dust, contributing to our knowledge and the potential implications for human health and the environment.</div></div>","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":"364 ","pages":"Article 125314"},"PeriodicalIF":7.6,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142637468","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":"Distribution, sorption patterns, and outflows of riverine microplastics-affiliated linear alkylbenzenes and polycyclic aromatic hydrocarbons in a dynamic coastal zone","authors":"Huiping Wen, Po Wang, Lei Mai, Xiangrong Xu, Kefu Yu, Eddy Y. Zeng","doi":"10.1016/j.envpol.2024.125295","DOIUrl":"https://doi.org/10.1016/j.envpol.2024.125295","url":null,"abstract":"Microplastics (MPs) pollution has emerged as a global concern. To mitigate the potential threats by MPs, particularly to coastal regions, it is crucial to comprehend the environmental behavior of MPs and their affiliated chemicals. In the present study, we collected floating MPs using a Manta net (0.33 mm mesh size) in a one-year sampling event in 2022 from the eight major estuaries in the Pearl River Delta, China, and also from five coastal sites in August and December in the same year. Nineteen linear alkylbenzenes (∑₁₉LAB) and 16 polycyclic aromatic hydrocarbons (∑₁₆PAH) affiliated with MPs were measured. The mean concentrations of MPs-affiliated ∑₁₉LAB and ∑₁₆PAH were 6710 (range: 3400–12300) and 5310 (range: 817–19,600) ng g^–1, respectively, at the estuarine sites, and were 4920 (range: 2400–7600) and 2610 (range: 911–7890) ng g^–1, respectively, at the coastal sites. Significant correlations were found between logarithmic MPs–water partition coefficients (log <em>K</em>_pw) and logarithmic suspended particulate matter–water partition coefficients (log <em>K</em>_d) values for LABs and PAHs, indicating analogous partitioning dynamics for MPs and suspended particulate matter with water. The annual riverine outflows were 1170 and 414 g for ∑₁₉LAB and ∑₁₆PAH, respectively. Although the riverine outflows of LABs and PAHs carried by MPs remain negligible compared to those by suspended particulate matter, an upward trend was identified between 2018 and 2022. Notably, the riverine input of LABs and PAHs carried by suspended particulate matter to the coastal ocean decreased from 2005/2006 to 2022, due to a combination of improved technological processes and energy structures.","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":"21 1","pages":""},"PeriodicalIF":8.9,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142637560","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":"Poly-γ-glutamic acid chelates chromium (III) and copper (II), alleviating their toxicity in cucumber and affecting rhizosphere bacterial community assembly","authors":"Chaoyang Chen, Wenhui Yan, Yu Chen, Sijie Liu, Chuangjiang Nong, Liang Sun, Rui Wang, Hong Xu, Peng Lei, Yian Gu","doi":"10.1016/j.envpol.2024.125318","DOIUrl":"https://doi.org/10.1016/j.envpol.2024.125318","url":null,"abstract":"The accumulation of chromium (Cr) and copper (Cu) in soil during industrialization and modernization poses an extreme threat to crops. Poly-γ-glutamic acid (γ-PGA) has the potential to stabilize heavy metals in soil through chelation because of the numerous carboxyl groups in its side chain. The rhizosphere microbiome contributes to plant detoxification by participating in heavy metal passivation. However, it is still unclear whether γ-PGA can alleviate the toxicity of Cr and Cu to plants and whether this effect is associated with changes in the rhizosphere microbiome assembly. Here, we found that γ-PGA application significantly reduced the content of Cr or Cu in cucumber plants by 67.45%-86.77% and 94.67%-98.21, respectively, and alleviated the oxidative stress of Cr or Cu to plants. Moreover, γ-PGA significantly increased the biomass of cucumber fruits in the plot experiment by 13.5% and 25.3% under Cr and Cu stress, respectively. The content of Cr or Cu in the cucumber fruit was below limits of detection, in contrast to the 31.23 mg/kg Cr or 9.86 mg/kg Cu detected in the no-γ-PGA treatment. γ-PGA effectively chelated Cr and Cu <em>in vitro</em>, and less than 30% of their chelates were degraded in 20 weeks, suggesting the strong stability of these chelates. γ-PGA significantly altered the rhizosphere bacterial community composition of cucumber by enriching phyla <em>Gemmatimonadota</em>, <em>Acidobacteriota</em> and <em>Firmicutes,</em> and genera <em>Gemmatimonas</em> and <em>Stenotrophomonas,</em> which potentially involved in reducing the mobility of Cr and Cu in soils. Furthermore, γ-PGA significantly enriched taxa assigned to plant growth-promoting bacteria (PGPB). Together, our results suggest that γ-PGA can reduce the Cr and Cu contents in cucumber, and this process is strongly associated with the chelation capacity of γ-PGA and its effects on rhizosphere microbiome composition. These results highlight the exciting potential to use γ-PGA for the remediation of heavy metal-contaminated soils.","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":"45 1","pages":""},"PeriodicalIF":8.9,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142637470","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}