Antibiotic resistance poses a significant threat to public health, and landfill leachate serves as a major reservoir for pharmaceuticals and personal care products (PPCPs) as well as antibiotic resistance genes (ARGs). Here, we conducted multi-sample analyses of the fate and driving mechanisms of PPCPs and ARGs in common landfill leachate treatment processes (“MBR+NF/RO,” “pretreatment + two-stage DTRO,” “biological treatment + AOP,” “pretreatment + MVR,” and “pretreatment + UF + RO + UV disinfection”) to comprehensively evaluate their associated risks. Results indicate that among all processes, “pretreatment + two-stage DTRO” achieves highly efficient and stable removal of 93.06–100% of PPCPs while significantly reducing the association between bacterial communities and ARGs in influent. The highest concentrations of ARGs in leachate were observed for multidrug resistance, macrolides, aminoglycosides, glycopeptides, bacillopeptides, and chloramphenicol, with “pretreatment + MVR” demonstrating the most stable removal efficiency for these ARGs. Key potential host bacteria carrying ARGs in the influent were Pseudomonadota, Bacillota, and unclassified_Bacteria, while only Pseudomonadota dominated in the effluent. “pretreatment + two-stage DTRO,” “pretreatment + MVR,” and “pretreatment + UF + RO + UV disinfection” reduced plasmid-encoded ARGs, but the absolute concentration of chromosomally encoded ARGs increased in all effluents. Furthermore, biological factors (microbes and MGEs) were the primary drivers of ARG presence, indicating that reducing microbial biomass and MGEs effectively enhances ARG removal rates. Our findings highlight that MGEs not only transmit ARGs across treatment processes but also significantly elevate their expression levels, providing crucial data for effective antibiotic resistance surveillance within the One Health framework.

The lack of recycling technologies for biodegradable plastics (BDPs) has led to significant resource wastage and limits its sustainable expansion. The inherent biodegradability of BDPs enables their depolymerization into low-molecular-weight intermediates, particularly under thermophilic conditions, which are subsequently channeled into microbial metabolic pathways for targeted conversion. Polyhydroxyalkanoates (PHA), a category of microbially synthesized BDPs characterized by high economic value and growing demand, offer a promising strategy for upcycling waste BDPs. This study focuses on Chelatococcus thermostellatus, a thermophilic PHA-accumulating microorganism that exhibits dual capabilities for simultaneous BDPs degradation and PHA biosynthesis under thermophilic conditions. This project employs thermophiles as chassis microorganisms for BDPs biorecycling. The thermophilic degradation mechanisms and bioassimilation pathways of various types of BDPs for PHA biosynthesis are systematically investigated, accompanied by characterization of the structural configurations and material properties of the synthesized PHA. Subsequently, a synthetic microbial consortium is constructed to regulate metabolic intermediates, with particular emphasis on elucidating the regulatory impacts of carbon source allocation in metabolic pathways on PHA synthesis efficiency. Process optimization is further implemented through the strategic modulation of operational parameters and environmental variables to enhance production performance. Additionally, the synergistic compatibility between mild chemical depolymerization and biological recycling is explored to establish an integrated system for improving PHA recovery efficiency. The findings are anticipated to provide theoretical foundations and technical frameworks to advance the high-value circular utilization of BDPs.

Rapid urbanization has transformed mega-cities into complex ecological systems, creating hotspots for vector-borne diseases. High population density, poor sanitation, and environmental degradation amplify the spread of pathogens transmitted by mosquitoes, ticks, and other arthropod vectors. These challenges are particularly acute in rapidly growing urban centers of West Africa, where emerging infectious threats intersect with gaps in biosecurity and public health infrastructure.

This study explores the ecological and socio-environmental drivers of vector proliferation, integrating field entomological surveys, spatial mapping, and risk modeling. Results highlight urban hotspots shaped by stagnant water, unmanaged waste, and microclimatic variability, while human mobility and socio-economic disparities intensify exposure risk. Conventional vector control strategies, when applied in isolation, are insufficient to address these multi-layered challenges.

A unique aspect of this research is its biosecurity focus: it evaluates how urban planning, infrastructure gaps, and early detection systems influence vulnerability to emerging infectious diseases. Integrating entomological surveillance with community engagement and predictive modeling enables proactive intervention, enhancing outbreak preparedness. Early detection of invasive vectors and real-time risk assessment provide actionable insights for municipal authorities and policymakers, supporting data-driven strategies that save lives and resources.

By bridging entomology, urban ecology, and public health policy, this study offers a replicable framework for resilient cities. While grounded in West African contexts, the findings are globally relevant, offering lessons for rapidly urbanizing mega-cities worldwide—including those in Asia—facing similar public health and environmental challenges.

In conclusion, safeguarding urban populations from vector-borne disease requires interdisciplinary collaboration, proactive biosecurity, and environmentally informed planning. This research demonstrates that sustainable urban health is inseparable from ecological stewardship and anticipatory public health strategies. By providing a model that combines local insights with global applicability, this study contributes to evidence-based policy, resilient urban planning, and improved health outcomes for urban populations.

Efficient control of carbon dioxide dosing is crucial for optimizing coagulation performance and maintaining the target pH in water treatment processes. This study presents the development of an artificial intelligence (AI) model to determine the optimal target pH for COâ‚‚ injection at the ‘G’ Water Treatment Plant. The model aims to automate the current manual decision-making process, reducing chemical costs and improving operational stability.

Key operational criteria for COâ‚‚ injection were analyzed, including raw water pH thresholds, seasonal variations, and the relationship between pH and coagulation efficiency. Historical plant data—such as turbidity, alkalinity, conductivity, temperature, and pH measurements from multiple process units—were collected and preprocessed. Input variables included parameters from intake, coagulation, and sedimentation stages, with the target pH as the dependent variable.

The AI model will identify the most influential factors affecting target pH and establish optimal dosing strategies under varying operational conditions. This research is expected to enhance automated pH control, reduce chemical usage, and support sustainable and cost-efficient water treatment operations.

This work demonstrates the potential of AI in optimizing chemical dosing strategies in water treatment, supporting both operational efficiency and regulatory compliance, while contributing to carbon neutrality goals by minimizing unnecessary COâ‚‚ usage and promoting more sustainable treatment practices.

<This research was supported by the Carbon Neutrality, a specialized program of the Graduate School through the Korea Environmental Industry & Technology Institute (KEITI) funded by Ministry of Environment (MOE, Korea).>

Forward osmosis (FO) has been adopted to treat complex wastewater such as mature landfill leachate due to its high rejection of organics^[1]. In this study, impacts of ozonation pretreatment enhanced FO membrane system treating mature landfill leachate wastewater were assessed to elucidate its concentration performance, membrane fouling, and transformation characteristics of dissolved organic matter (DOM). For the FO process, it was observed that when ozone pretreatment was applied under a controlled recovery rate, the processing time was significantly reduced and a final membrane flux was greater than that of the without ozonation. Ozonation pretreatment of landfill leachate, conducted at varying durations, revealed that the processing time for FO treatment of old landfill leachate progressively decreased with extended ozone exposure. Interestingly, for medium landfill leachate, prolonged ozone exposure led to an increase in FO processing time. The reversibility of fouling resistance, contact angle, scanning electron microscopy (SEM), and atomic force microscop (AFM) analysis proved that optimal ozone exposure times for medium and old landfill leachate were determined to be 10 h and 40 h, respectively, and optimal ozone pretreatment mitigated membrane fouling, manifested by reduced hydrophobicity, decreased surface fouling, and lowered surface roughness. Fourier transform infrared spectrometer (FTIR) analysis suggests the presence of contaminants such as polysaccharides and proteins on membranes. The exacerbation of membrane fouling observed with the excessive introduction of ozone during the treatment of medium landfill leachate may be attributed to an increase in soluble extracellular polymeric substances and low molecular weight substances^[2]. Besides, the changes in the leachate composition along the treatments were tracked by excitation-emission matrix-parallel factor analysis (EEM-PARAFAC) to identify fulvic-like (C1), protein-like (C2), and soluble microbial by-product-like (C3) components^[3]. The Fmax of C1 and C2 exhibit a decreasing trend for medium landfill leachate, and the Fmax of C1 on the membrane was found to be significantly lower than that of C2. For old landfill leachate, the C3 shows resistance to degradation with the increase in ozone, while the variations in C1 and C2 on the membrane are similar between medium and old landfill leachate. Meanwhile, the concentrations of humic substances and amino acids were further quantified, revealing that the concentration of fulvic acid significantly exceeded that of humic acid and the amino acids were primarily composed of components L-Histidine, L-AsparticAcid, and L-(+)-Lysine. In the catalytic process of landfill leachate by ozone, the main free radicals involved were ^•OH and ^• , which play a role in the degradation of organic compounds.

The dissemination of plasmid-mediated antibiotic resistance genes (ARGs) in the environment has become a global threat to ecological security and human health. In contrast to previous studies focusing mainly on abiotic factors such as coexisting pollutants affecting plasmid conjugation, this study reveals for the first time that typical microbial metabolites of carbon (COâ‚‚), nitrogen (NO), and sulfur (Hâ‚‚S) are important yet overlooked biological drivers facilitating the spread of ARGs. These metabolites modulate the efficiency of plasmid conjugation by inducing various microbial stress responses, including oxidative, nitrosative, and reductive stress, which alter the cell surface properties of donor and recipient bacteria, intracellular key ion levels, and amino acid metabolism. Taking Hâ‚‚S as an example, even at environmentally relevant concentrations, it significantly enhances the conjugation frequency of plasmid RP4 within sewage microbial communities and expands its transmission range. Mechanistic investigations demonstrate that Hâ‚‚S exposure activates the plasmid RP4-encoded protein Upf32.8, thereby relieving the suppression of genes encoded by plasmid RP4 and intensifying its hijacking of glutamine metabolism in donor bacteria. Notably, evolutionary analysis shows that GlsS32.8 is conserved across globally prevalent IncP-1α plasmids, underscoring a universal risk of ARG spread in H₂S-rich environments. These findings provide novel theoretical perspectives and a scientific basis for understanding and controlling the environmental spread of antibiotic resistance genes.

ABSTRACT: Microcystin-LR (MC-LR) is typically produced along with the occurrence of cyanobacterial blooms, potentially exerting deleterious effects on intestinal health in aquatic animals. To date, the underlying mechanism by which MC-LR affects intestinal health remains elusive. In this study, adult male zebrafish were exposed to MC-LR to assess its impact on intestinal health from the perspectives of histopathology, microbiome and metabolome. Histopathological and biochemical results indicated that MC-LR damaged intestinal villi and epithelial cell, induced intestinal barrier injury and inflammatory response in zebrafish. Metabolomics results indicated that MC-LR induced the dysbiosis in amino acid, carbohydrate, lipid, energy metabolisms, and specifically altered glycine, serine and threonine metabolism in amino acid metabolism. Metagenomics results demonstrated that MC-LR altered the composition of intestinal microbiota, perturbed the microbial functions associated with amino acid, lipid, carbohydrate and energy metabolisms, as well as barrier function and inflammatory response. Multiomics analyses further confirming MC-LR caused the dysfunction of glycine, serine and threonine metabolism, which was precisely regulated by dominant Proteobacteria, Firmicutes, Fusobacteriota and Bacteroidota. This study offers a novel perspective on the toxicity of microbiota and microbiota-derived metabolism in fish intestines induced by MC-LR and deepens our comprehension of the disruptive influence of MC-LR on intestinal homeostasis in organisms.

The diversified utilization of biomass energy has gained substantial attention in recent years. Among various technologies, hydrothermal treatment (HTT) is highly effective for processing organic solid waste with high moisture content and low biodegradability while facilitating the fixation of organic carbon. However, HTT produces hydrothermal wastewater (HTWW) as a by-product, which differs from conventional wastewater due to its high concentrations of phenols, ketones, pyridines, and other refractory compounds that are challenging to degrade. Addressing this issue is critical for advancing sustainable waste management.

To achieve dual resource and energy recovery in organic solid waste treatment, we propose integrating HTT with anaerobic digestion (AD) to enable comprehensive waste processing. This study systematically investigated the characteristics of HTWW under varying raw material types and hydrothermal conditions. The results revealed that higher hydrothermal temperatures and longer residence times generate more refractory compounds, which adversely affect the efficiency of subsequent anaerobic digestion.

To enhance the performance of coupled AD technology, we evaluated four strategies: optimization of process conditions, separation of refractory compounds, hydrochar enhancement, and coagulation-adsorption pretreatment. Each approach demonstrated potential in improving anaerobic digestion efficiency to varying degrees. This work provides a theoretical framework for optimizing HTWW treatment through AD and offers practical insights for enhancing biomass conversion efficiency.

Currently, the in-situ application of iron anode-assisted constructed wetlands (IACWs) in micro-polluted secondary effluent is an ideal solution for ensuring zero-valent iron reactivity, compensating for cold-impaired microbial denitrogenation, and effectively removing nitrogen and phosphorus. Meanwhile, the emergence of solar cells brings the dawn for large-scale application of IACWs without energy consumption concern. To the best of our knowledge, most of the hitherto-reported studies focused on the effects of distinct voltage levels (VLs) on nutrient removal efficiencies in IACWs, and failed to holistically elucidate the pivotal role of VL on nutrient eliminations from the aspects of electrocatalytic behaviors and microbiological mechanisms (community succession, interspecies interactions, and metabolism features), which further impedes establishing performance-pathway-community connections. More importantly, little information is available on the dynamical variations of electrochemical and microbial nutrient removals at various VLs, especially taking water temperature (WT) variations into account. Herein, five solar-driven IACWs at 0, 1, 5, 10, and 15 V were established to treat secondary effluent for 109 days across moderate to low WTs. Results showed that total nitrogen (TN) (4.87 ~ 54.42%) and total phosphorus (TP) (20.66 ~ 97.35%) removals both ascended as VL raised, which primarily occurred in the cathodic regions and anodic upstream, respectively. More sustainable nitrogen elimination was achieved at lower VLs (≤ 5 V). Electrochemical contribution quantification revealed that electrochemical denitrogenation strengthened as VL improved (144.3 ~ 965.7 mg m^-2 d^-1), whereas severe anodic hardening and cathodic clogging in later operation impaired the dominant electrochemical denitrification at higher VLs (≥ 10 V). In contrast, microbial denitrogenation followed hump-shaped variational pattern with rising VL (peaked at 5 V). Microbial community and function analyses further clarified that despite VL elevation induced denitrifying microbiota evolution and up-regulated functional gene abundance, microbial denitrification function was significantly constrained at higher VLs. Particularly, the highest network complexity (at 1 V) and modularity (at 5 V) bred IACWs to better withstand low WT and high iron concentration. Overall, 5 V balanced electrochemical and microbial denitrogenation to obtain persistently effective TN removal. Nonetheless, 15 V would be more suitable to deal with sudden surges in influent nutrient load. Additionally, intensified electro-coagulation dephosphorization was verified to remove most TP via adsorption and co-precipitation. This work provided a preferred VL regulation strategy to facilitate in-situ sustainable nutrient purification of low-polluted wastewater in IACWs, and has practical significance for CW administrators seeking to comprehend the outcomes of VL modulation and maintain well-tuned solar-driven IACWs for nutrient eliminations.

Industrial fluoride (F^-) wastewater threatens the stability of biological treatment systems. However, the adaptive evolution of nitrogen-transforming microorganisms and the spread of antibiotic resistance under long-term F^- stress remain unclear. This study systematically investigated the nitrogen removal performance, microbial community structure, and resistome evolution in a sequencing batch bioreactor under prolonged (120-day) stress from 20 mg/L F^-. The results indicated that long-term F- exposure severely inhibited nitrification, decreasing the ammonia removal efficiency from 99.6% to 74.7% and the specific ammonia oxidation rate (SAOR) by 23.8%. In contrast, a significant enrichment of denitrifying bacteria (e.g., Thauera abundance increased by 274%) enhanced denitrification, boosted the specific nitrate reduction rate (SNRR) by 48.7%, and maintained a stable total inorganic nitrogen (TIN) removal efficiency (64.5%). To counteract F^- toxicity, the microbial community exhibited multi-level adaptations, including enhanced secretion of extracellular polymeric substances (EPS), upregulation of antioxidant and energy metabolism genes, and increased F- efflux capacity. Crucially, F^- stress co-selected for broad-spectrum antibiotic resistance genes (ARGs) and heavy metal resistance genes (MRGs), with total abundances increasing by 19.7% and 31.2%, respectively. Network analysis confirmed that denitrifying bacteria, which gained a competitive advantage under F^- stress, were the primary hosts of these resistance genes. This study reveals the evolutionary mechanisms of nitrogen-converting microbes in the treatment of fluoride-containing wastewater and warns of the potential risks of resistance gene proliferation induced by F^- pollution.