Fomesafen, a persistent diphenyl ether herbicide, causes carry-over phytotoxicity and threatens agricultural soil ecosystems. Here, the previously isolated fomesafen-degrading strain Klebsiella variicola W28 was used to elucidate a cross-kingdom rhizosphere signaling mechanism linking soybean root exudates to bacterial colonization and fomesafen degradation. Untargeted metabolomics showed that fomesafen stress selectively enriched glycitein in soybean root exudates. Glycitein enhanced W28 chemotaxis, motility, biofilm formation, and root-surface colonization, while metagenomic and random forest analyses revealed the assembly of a cooperative rhizosphere consortium enriched in Azotobacter, Klebsiella, cobB, and pcaG/H. Mechanistically, glycitein activated purine metabolism and the NAD+ salvage pathway, thereby supporting the NAD+-dependent deacetylase CobB. GST pull-down, BiFC, and LCA confirmed direct CobB-LysR-pca interaction. EMSA showed that LysR-pca repressed the pcaGH promoter, whereas CobB-mediated deacetylation weakened DNA binding and relieved transcriptional repression. Molecular docking and product profiling demonstrated that heterologously expressed PcaGH directly transformed fomesafen, producing benzoic acid. Pot experiments confirmed that glycitein enhanced W28-mediated fomesafen degradation in soil. These findings define a root exudate-NAD+ homeostasis-lysine deacetylation-pcaGH activation circuit, reveal how plant signals coordinate rhizosphere recruitment with intracellular catabolic activation, and provide a mechanistic basis for precision in situ bioremediation of diphenyl ether-contaminated soils.

Ionic liquids (ILs) are regarded as environmentally friendly solvents due to their favorable physicochemical properties, including low volatility and high thermal stability. However, their high water solubility and poor degradation pose potential threats to aquatic ecosystems. Based on domestic and international research, the present study systematically reviews the toxic effects of ILs on multi-trophic-level organisms in aquatic food chains, including producers, primary and secondary consumers, and summarizes the toxic mechanisms of ILs in aquatic organisms. It also delves deeply into the key factors that influence the toxicity intensity of ILs. In addition, a comprehensive quantitative analysis of the large existing dataset is conducted, and the results of the Meta-analysis further reveal the impacts of different types of ILs and exposure conditions on aquatic organisms. These research results provide a theoretical basis and technical support for the green application of ILs, the assessment and early warning of ecological risks, and guidance for future research on ILs.

Aged microplastics (MPs) have attracted growing concern about their carrier effects. Yet, the impact of soil freeze-thaw cycles (FTCs) on MPs as contaminant carriers remains poorly understood. This study assessed changes in the carrier potential of FTC-aged MPs for antibiotics (ATs) through adsorption experiments, and disentangled their underlying mechanistic pathways by innovatively integrating characterization, batch adsorption and density functional theory (DFT) data within a partial least squares structural equation modeling (PLS-SEM) framework. Results showed that soil FTCs roughened surfaces, altered wettability and surface charges, and increased oxygen-containing functional groups (OCFGs) of MPs. The adsorption capacities for sulfamethoxazole (SMX) and enrofloxacin (ENR) were generally enhanced on FTC-aged MPs across MP types and environmental conditions, indicating strengthened carrier potential. Mechanistically, the dominant driver was the FTC-altered surface morphology of MPs that promoted pore-filling, while FTC-generated OCFGs played a limited and polymer-specific role by remodeling the electronic structure of MPs, thereby modulating their electrostatic and hydrogen-bonding interactions with ATs. This study establishes a transferable framework for adsorption research, advances understanding of the carrier potential of MPs undergoing FTCs in soils, and calls for greater attention to the overlooked role of FTCs in shaping co-contamination risks in cold region ecosystems under climate change.

Ground-level ozone pollution has emerged as a significant environmental risk factor for diabetic kidney diseases, yet the underlying mechanisms and potential interventions remain poorly defined. This study investigated the nephrotoxic effects of ozone in a diabetic model, wherein male db/db mice were exposed to ozone (0.25 or 1.0 ppm) for 8 weeks. Moreover, dapagliflozin (DAPA) and Yishen Huashi Granules (YSHS), pharmaceutical agents commonly used to treat metabolic and renal diseases, were applied to investigate their therapeutic potential against ozone-caused kidney insult. Our data demonstrated that ozone exposure could exacerbate hyperglycemia and structural renal damage, including glomerular basement membrane thickening, podocyte fusion, and fibrogenesis. Furthermore, ozone exposure disrupted the splenic Th17/Treg balance, enhanced IL-17 production, and promoted renal inflammation through upregulating RORγt/IL-17A signaling pathway. These findings suggested that ozone exposure could accelerate diabetic nephropathy progression by reshaping the systemic immune landscape. Notably, DAPA and YSHS, especially their combination, showed the potential to mitigate kidney injury by ozone through synergistically restoring glucose homeostasis, Th17/Treg balance and RORγt/IL-17 signaling to suppress systemic and local inflammation. This study provided valuable insights into the nephrotoxic effects associated with ozone exposure, and offered a reference for the development of intervention strategies targeting pollutant-driven metabolic kidney disease and the formulation of environmental regulations.

Arid and semi-arid agroecosystems cover nearly half of global croplands and face escalating threats from microplastic (MP) pollution. Current empirical research has predominantly focused on MP toxic effects on individual soil microbial groups. However, few systematic investigations have addressed multitrophic responses of soil food webs or developed an integrated mechanistic framework to synthesize such trophic changes. Herein, we establish a holistic soil food web-centred framework to disentangle MP-induced ecological alterations specific to arid and semi-arid agroecosystems. A core novelty of our framework lies in identifying soil food web energy flux as a potential underappreciated mediator linking biodiversity to ecosystem functioning (BEF) under MPs pollution. We further delineate major outstanding knowledge gaps: the context dependence of MPs effects, the scarcity of food web-scale empirical evidence, the mediating role of energy flux, potential interactive effects with other chemical stressors, and the absence of evidence-based restoration strategies. Addressing these bottlenecks demands a paradigm shift from single species toxicology to multifactorial, food web level research. Taking plastic-mulched agroecosystems across Northwest China as a global testbed, this study constructs a testable conceptual framework to elaborate context-specific cascading mechanisms of microplastic pollution unique to drylands. Our synthesized framework provides targeted theoretical guidance for mitigating MP-triggered soil food web degradation and sustaining the long-term sustainability of arid agroecosystems worldwide.

Agricultural mulch films are widely applied to increase crop productivity but are a significant source of microplastics (MPs) in the environment. We investigated the incorporation of conventional and biodegradable MPs into soil aggregates from agricultural fields in Finland, Germany and Spain, hypothesising that (i) MPs become increasingly occluded within soil aggregates over time, (ii) the extent of occlusion differs between conventional and biodegradable MPs, and (iii) occluded MPs differ in morphology and surface characteristics from free MPs. Arable fields were spiked with MPs derived from either a biodegradable polybutylene adipate terephthalate-starch blend (PBAT/starch) or conventional linear low-density polyethylene (LLDPE) mulch films. Soil samples were collected after two barley-growing seasons, separated into free and occluded fractions, and analysed using digital microscopy and deep learning to quantify MP abundance, size and shape. Surface properties were assessed using scanning electron microscopy. Total MP abundance declined between cropping seasons for both polymer types, while the proportion of aggregate-occluded MPs increased, reaching 76% for PBAT/starch and 65% for LLDPE. Soil exposure altered the size, shape and surface properties of MPs in a polymer-specific manner. Occluded PBAT/starch MPs were larger and more solid than their free counterparts, consistent with protection against weathering and fragmentation within aggregates. Occluded LLDPE MPs were smaller than free particles but also exhibited higher solidity, likely reflecting preferential incorporation of particles with smoother, more uniform edges. We conclude that soil aggregate occlusion is a key mechanism governing MP fate in agricultural soils, promoting particle stability while simultaneously reducing mobility and bioavailability.

Hexavalent chromium [Cr(VI)] detoxification by fungi is environmentally important, yet the metabolic basis that sustains extracellular non-enzymatic Cr(VI) reduction remains elusive. This study investigated extracellular Cr(VI) reduction and metabolic reprogramming in the Cr(VI)-tolerant filamentous fungus Penicillium oxalicum SL2. P. oxalicum SL2 efficiently reduced Cr(VI), with reduction efficiencies of 99.50 ± 0.57%, 38.54 ± 0.76%, and 29.84 ± 3.41% after 48 h at 100, 200, and 400 mg/L Cr(VI), respectively. At 100 mg/L Cr(VI), reduction was primarily mediated through an extracellular non‑enzymatic pathway, with cell‑free supernatant contributing over 90.0% of the total reduction activity. Metabolomics showed a concentration‑dependent adaptive strategy, with localized metabolic adjustment at 100 mg/L, coordinated carbon-nitrogen reprogramming at 200 mg/L, and membrane lipid stress at 400 mg/L. Integrated metabolomics and proteomics further revealed that 200 mg/L Cr(VI) redirected carbon metabolism toward fatty acid β-oxidation and the glyoxylate cycle, promoting the production of low‑molecular‑weight organic acids (e.g., glyoxylate) associated with acidification and extracellular Cr(VI) reduction. Meanwhile, suppressed inorganic nitrogen assimilation was accompanied by enhanced branched‑chain amino acid catabolism and transamination, supporting redox homeostasis and stress adaptation. These findings demonstrate that P. oxalicum SL2 coordinated carbon-derived reductant production and nitrogen-regulated redox balance to sustain Cr(VI) detoxification, providing mechanistic insights into fungal-based Cr(VI) bioremediation.

Strong biofilm-forming multidrug-resistant (MDR) Escherichia coli (E. coli) can persist on food-contact surfaces and contribute to contamination along the food production chain. In this study, we investigated the occurrence, genomic features, and plasmid transferability of strong biofilm-forming E. coli from food-producing animals and associated farm environments, and evaluated an approach for controlling their surface-associated biofilms. Among 536 isolates, 42 were classified as strong biofilm producers (7.84%, 42/536). The highest proportion was observed in pig-derived isolates (10.11%, 36/356), followed by duck-derived (3.70%, 3/81) and chicken-derived isolates (3.03%, 3/99). These isolates showed diverse sequence types and phylogroups. The biofilm-associated genes csgG, flgCD, and fliA were detected in all strong biofilm producers, whereas the adhesin gene cluster mrkABCDF was present in 24 isolates (57.1%, 24/42). Conjugation assays yielded 26 transconjugants, of which 14 retained strong biofilm-forming capacity. Among 13 sequenced transconjugants with analyzable plasmids, 11 carried complete mrkABCDF clusters, mainly on IncX1 plasmids. Public genome comparison further identified highly similar plasmid backbones across 550 public E. coli genomes from diverse host, geographic, and ecological sources, suggesting that biofilm-associated plasmids are not restricted to a single clonal lineage. Benzalkonium bromide combined with lysozyme reduced biofilm biomass, extracellular matrix production, bacterial aggregation, and surface colonization on glass, stainless steel, and polyvinyl chloride. Overall, these findings suggest that transferable mrkABCDF-bearing plasmids, particularly IncX1 plasmids, may serve as potential genetic vehicles for persistence-associated traits in MDR E. coli, and that benzalkonium bromide-lysozyme treatment may provide a candidate strategy for reducing biofilm persistence on food-contact surfaces.

N-isopropyl-N'-phenyl-1,4-phenylenediamine (IPPD) is a critical rubber antioxidant and a promising alternative to N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD). Its photochemical fate at soil-mineral interfaces remains insufficiently elucidated, particularly regarding the mineral-dependent transformation behaviors. In this study, the phototransformation of IPPD on the surfaces of silica (SiO2) and montmorillonite (MMT) was systematically investigated under simulated sunlight irradiation. IPPD underwent rapid degradation following pseudo-first-order kinetics, with significantly different transformation rates and pathways observed between SiO2 and MMT systems. The degradation process was notably regulated by surface pH, moisture content, natural organic matter, and coexisting ions. Mechanistic investigations via quenching experiments and electron paramagnetic resonance (EPR) spectroscopy demonstrated that direct photolysis was the dominant pathway in the SiO2 system, whereas reactive oxygen species (1O2 and •OH) governed the photodegradation process in the MMT system. Multiple transformation products (TPs) were generated in both systems, with IPPD quinone (IPPD-Q) identified as a common intermediate. Notably, Vibrio fischeri bioluminescence assays revealed a distinct "toxicity peak" during the photolysis process, and computational toxicology further suggested that specific TPs exhibited enhanced acute toxicity, carcinogenicity, and endocrine-disrupting potential compared to the parent compound IPPD. These findings clarify the critical role of mineral types in governing the interfacial photochemical behavior, environmental persistence, and hazard of IPPD, and provide compelling support for the inclusion of matrix-specific transformation products in the environmental risk assessments of rubber additives.

This study presents a comprehensive 15-year (2009-2023) assessment of persistent organic pollutants (POPs) in the Spanish atmosphere to evaluate the Stockholm Convention's effectiveness. Polyurethane foam passive samplers were deployed across 23 sites to monitor legacy pesticides and industrial chemicals. Results reveal a concentration hierarchy dominated by hexachlorobenzene (HCB), which accounted for a median of 41% of the ∑POP concentrations and displayed a remote-enriched spatial pattern characteristic of global distillation. In contrast, legacy pesticides and indicator polychlorinated biphenyls (iPCBs) were influenced by temperature-dependent secondary volatilization from historically contaminated soils, as indicated by Clausius-Clapeyron analyses. These compounds frequently exhibited an unexpected urban enrichment likely associated with heat island effects, while polybrominated diphenyl ethers (PBDEs) displayed a pronounced urban gradient (a 35-fold increase from remote baselines) driven by the late-regulated BDE-209. Long-term temporal analyses underscore a sharp regulatory dichotomy. Early-banned compounds, such as endosulfan, HCB and dichlorodiphenyltrichloroethane (DDT), and lighter PBDEs, are experiencing rapid environmental depletion, with significant annual declines of up to -33%. Conversely, pentachlorobenzene (PeCB), iPCBs, and BDE-209 show stalled or locally increasing trends (up to +20%), sustained by unintentional combustion, active consumer goods, and regulatory lag times. Altitudinal profiling across Tenerife sites highlights this divergence: coastal areas reflect local secondary emissions, whereas high-altitude observations confirm the progressive clearance of the global free troposphere. Overall, these findings provide new insights into the spatial and temporal dynamics of atmospheric POPs, reaffirming the role of long-term monitoring in guiding international abatement strategies.

The extensive use of the herbicide acetochlor has led to its widespread detection in water sources, resulting in its recent inclusion as a regulated contaminant in China's updated Drinking Water Quality Standards (GB5749-2022). This study investigates a chemical-free approach using far-UVC (222 nm) radiation for the sustainable control of acetochlor in drinking water. Acetochlor exhibited substantially enhanced direct photolysis under UV222, with a fluence-based decay rate constant (1.06 × 10⁻2 cm2 mJ⁻1) approximately 13.33-fold higher than that under UV254 (7.95 × 10⁻4 cm2 mJ⁻1) in buffer, and the direct UV222 photolysis of acetochlor in real surface water and tap water followed pseudo-first-order kinetics, with degradation rate constants enhanced by 28.34-fold and 19.11-fold, respectively, compared to conventional UV254 treatment. The apparent quantum yields for acetochlor photolysis at 222 nm were determined as 0.36 molecule einstein-1. While nitrate exhibited a negligible effect under UV254, it promoted acetochlor degradation under UV222. Residual disinfectants (chlorine, monochloramine, and chlorine dioxide) in tap water enhanced acetochlor degradation by UV254 but had minimal impact on the UV222 process. By combining experiments with kinetic modeling, we quantified the radical concentrations generated from disinfectant photolysis at 222 nm and 254 nm, enabling a direct comparison of radical generation potential and micropollutant degradation efficiency between the two wavelengths. The formation profiles of trihalomethanes (THMs) and haloacetic acids (HAAs) during UV222 treatment in the presence of residual disinfectants were distinct from those observed with UV254 treatment, with or without post-chlorination. These findings provide critical insights into the photochemical behavior of acetochlor and highlight the potential of far-UVC as an effective, chemical-free technology for controlling persistent herbicides, offering a promising strategy for compliance with increasingly stringent water quality standards.

Partial denitrification (PD) is a promising strategy for sustainable nitrite supply to anammox systems, yet its practical application in industrial wastewater treatment is often constrained by simultaneous heavy metal and salinity stress. This study investigated the long-term role of betaine as an osmoprotective regulator in restoring PD granular sludge exposed to Cd(II) (80 mg/L) and elevated salinity (20-60 g/L NaCl). Under initial stress without betaine, nitrate reduction was severely inhibited and nitrite accumulation was below the detection limit. Betaine supplementation substantially restored reactor performance, increasing the specific nitrite production rate from 5.35 ± 0.51-73.65 ± 2.92 mg N/g VSS/h and promoting stable nitrite accumulation under moderate salinity (20-40 g/L NaCl). Further studies showed that betaine may have stimulated extracellular polymeric substance (EPS) secretion, particularly proteins, potentially enhancing granule aggregation and structural stability. It also reshaped microbial communities by enriching stress-tolerant taxa while maintaining the core PD-related genus (Thauera). However, under extreme salinity (60 g/L NaCl), microbial activity, EPS, and granule size declined markedly, and the recovery efficiency of betaine was relatively low. Granule size further governed system resilience: due to stable spatial frameworks, large granules (d > 0.5 mm) are able to withstand combined stress shocks, making it easier to maintain stable performance when betaine is added. In contrast, small granules (d < 0.5 mm) have a simple structure and exhibit impaired performance. These findings demonstrate that betaine can effectively enhance PD robustness under combined Cd(II) and salinity stress, while maintaining large and structurally intact granules is critical for maximizing its protective effects.

Per- and polyfluoroalkyl substances (PFAS) pose long-term risks to ecosystems and human health because of their persistence, bioaccumulation, long-range transport, and toxicity. Focusing on the Northeast Black Soil Region of China, a major grain production base with intensive agricultural activities and complex industrial inputs, this study developed a comprehensive analytical framework integrating multi-source data (2005-2025), including literature, environmental monitoring, soil properties, and toxicity databases. The framework combined meta-analysis, principal component analysis (PCA), machine learning, and entropy-weight-based risk assessment to systematically characterize PFAS pollution patterns, spatial heterogeneity, and priority risks. Random-effects meta-analysis revealed moderate-to-strong positive correlations among PFAS congeners (pooled effect size = 0.336) with significant heterogeneity (I² = 96.80%). PCA showed that the first two principal components explained over 48% of the total variance, whereas six components accounted for more than 85%. Among eleven machine-learning models, Logistic Regression achieved the best performance and stable generalization when the sample size exceeded 60 samples. SHapley Additive exPlanations (SHAP) identified latitude, longitude, and soil organic carbon as the dominant predictors. Risk assessment indicated that PFOS and PFOA exhibited the highest priority levels (ToxPi: 0.872 and 0.499; EHPi: 0.839 and 0.679), whereas approximately 60% of PFAS were classified as low risk and 20% as medium-to-high risk. This framework provides quantitative support for targeted PFAS management and offers a transferable strategy for regional-scale assessment of emerging contaminants.

Plutonium released into the environment through nuclear activities poses significant ecological risks due to its high toxicity and long-term radiological hazards. Understanding Pu transport in groundwater is critical for contamination remediation, yet existing models often overlook competitive adsorption of Pu between mobile colloids and immobile phases (e.g., rock grains). In this study, competitive partitioning experiments of Pu(IV) in a three-phase system (water-granitic colloid-granite grain) were conducted under anaerobic conditions at pH 8.15. Thermodynamic calculations were performed to investigate the surface complexation of Pu (in different valence states) with hydroxyl groups (SOH) on granitic colloids. Experimental results demonstrate that increasing granitic colloid concentrations (5.1-774.4 mg/L) significantly enhanced Pu(IV) partitioning into the colloidal phase, with the colloidal fraction (Fcol) rising from 33.36% to 87.50%, while the immobile Pu(IV) fraction (Fim) decreased from 59.50% to 12.11%. Thermodynamic modeling identifies ≡SOPuOH3 (84.7%) and ≡SOPuOH4- (15.3%) as the dominant Pu(IV) surface complexes, with their concentrations positively correlated to colloid levels. These two surface complexes formed via Pu4 + complexation with SOH on colloid surfaces, confirmed by stable species ratios (5.5:1) across colloid concentrations. Notably, Pu(IV) pseudo-colloids, rather than intrinsic-colloids from hydrolysis, govern Pu(IV) mobility at trace concentrations (2.48 × 10-10 mol/L in this study). These findings highlight the critical role of natural colloids in enhancing Pu transport by outcompeting immobile granite surfaces, emphasizing the necessity of incorporating colloid competition into predictive models for accurate environmental risk assessment.