Search Results (288)

Background/Objectives: Wastewater-based antimicrobial resistance (AMR) surveillance typically relies on treatment plant influent as a single integrated matrix, obscuring source-specific signals. In arid settings where treated effluent is reused, understanding how resistomes and virulomes are structured across wastewater compartments is essential for One Health monitoring. Methods: Shotgun metagenomic sequencing was applied to 57 wastewater samples collected in Dubai, United Arab Emirates, between October 2024 and January 2025. Samples represented nine community sewer nodes, two tertiary-care hospital outflows, and influent and effluent from two wastewater treatment plants (WWTP). Datasets were used for taxonomic, resistome, and virulome profiling. Alpha diversity was compared using Wilcoxon rank-sum tests, beta-diversity differences were assessed using permutational multivariate analysis of variance, and source-associated AMR genes were identified using linear discriminant analysis effect size analysis. Results: A total of 1470 bacterial species, 822 antimicrobial resistance genes (ARGs), and 1554 virulence factor genes were identified. Bacterial diversity was significantly lower in WWTP effluent than in other compartments. Hospital wastewater was enriched for class D β-lactamases, including multiple bla_OXA variants, whereas community wastewater and WWTP influent shared dominant macrolide and aminoglycoside resistance genes including msr(E), mph(E), strB and aadA1. Despite marked reductions in bacterial diversity after treatment, no significant difference in ARG diversity was observed between WWTP influent and WWTP effluent (p = 0.558), with resistance genes such as bla_VEB, msr(E), mph(E) detected in the latter. Virulome profiles shifted from fimbrial gene dominance in untreated sources toward biofilm- and persistence-associated genes in WWTP effluent. ARG alpha diversity varied over time, whereas taxonomic and virulome diversity remained stable. Conclusions: Community and influent wastewater capture population-level AMR carriage, hospital outflows concentrate clinically relevant resistance determinants, and WWTP effluent retains resistance markers despite microbial biomass reduction. Compartment-resolved metagenomic surveillance provides a practical One Health framework for identifying high-value monitoring points. Full article

Background/Objectives: Hospital water and wastewater environments are potential reservoirs for antimicrobial resistance genes (ARGs), particularly in high-risk clinical units. This study examined site-specific ARG DNA detection patterns in wet and waste-associated sites of a haematology ward and an intensive care unit (ICU) to identify environmental hotspots that may inform targeted infection prevention and control (IPC) interventions. Methods: A descriptive point-prevalence environmental study was conducted in May 2025 in a tertiary acute-care hospital. Samples were collected after routine cleaning and during usual clinical activity. Real-time PCR assays were used to detect bla_TEM, bla_SHV, bla_CTX-M, bla_OXA-48-like, bla_VIM, bla_NDM, bla_IMP, bla_KPC, and mcr-1. Analytical summaries included samples meeting predefined quality-control criteria. Ct signals were categorised descriptively; Ct values ≤ 40 were considered positive, with Ct values 36–40 classified as very low molecular signals, whereas Ct values > 40 were considered negative. Results: The analytical dataset comprised 60 samples: 31 from haematology and 29 from ICU. At least one included ARG signal was detected in 40/60 samples (66.7%), including 23/31 haematology samples (74.2%) and 17/29 ICU samples (58.6%), bla_TEM (51.7%) and bla_SHV (43.3%) were most frequent. Sink drains showed the broadest multi-gene profiles, especially combinations of ESBL- and carbapenemase-associated genes. Haematology showed broader carbapenemase-associated diversity, whereas ICU detections clustered in patient-room sink drains and sluice-room wastewater infrastructure. Conclusions: ARG DNA signals were unevenly distributed, with sink drains representing most frequently positive sampling sites for multi-gene detection. This molecular, single-timepoint environmental study does not demonstrate viable organisms, colonisation, or transmission; however, point-prevalence environmental assessments may identify wet and wastewater-associated hotspots that can inform targeted IPC interventions against the spread of multidrug-resistant microorganisms. Full article

Owing to their widespread occurrence, pharmaceutical and personal care products (PPCPs) have emerged as a global environmental concern; however, research on PPCP pollution in karst tourist cities remains limited. This study investigated the concentrations and spatial distribution of 43 PPCPs in the Lijiang River Basin and identified their primary sources together with the associated ecological and health risks. In total, 43 target PPCPs were detected in the Lijiang River Basin in Guangxi, China, with concentrations ranging from 68.6 to 3170 ng/L in wastewater, 53.2 to 1400 ng/L in surface water, and 32.0 to 505 ng/L in groundwater. Caffeine (CAF), 1,7-dimethylxanthine (1,7-DIM), 4-acetaminophenol (APAP), and metformin (MFM) were the predominant contaminants across all three matrices. Notably, concentrations in tributaries exceeded those in the main stem. Principal component analysis (PCA) revealed that domestic sewage and hospital wastewater constitute the principal sources of PPCPs in the Lijiang River. Certain effluents and river reaches containing 1,7-DIM and MFM posed a moderate ecological risk (0.1 < risk quotient (RQ) < 1). The PPCPs detected in groundwater did not exceed health-based thresholds, indicating no direct risk to human health. These findings advance our understanding of PPCP contamination in karst landscapes and provide a scientific basis for water quality management in the Lijiang River Basin. Full article

With the rapid development of nuclear medicine, the safe and sustainable management of medical radioactive wastewater has become an increasingly critical challenge at the interface of radiation protection and environmental engineering in China. Current management practices primarily focus on end-of-pipe treatment, whereas systematic frameworks integrating wastewater generation, collection, treatment, monitoring, and risk-informed discharge remain insufficient. In this narrative review, we systematically examine the complete management chain of medical radioactive wastewater, from generation to discharge, by evaluating source reduction strategies, available treatment technologies, and international regulatory frameworks, while also summarizing the requirements for whole-process monitoring and occupational radiation protection. We characterize the pollution profiles and discharge loads associated with major medical radionuclides, assess the applicability of different treatment technologies under various operational scenarios, and analyze key differences between Chinese and international regulatory approaches. Based on these analyses, we first establish a hierarchical decision matrix for treatment process selection considering hospital classification and site-specific constraints, and subsequently propose a six-tier end-to-end management framework integrating source reduction, source characterization, multi-constraint process selection, tiered treatment intensification, multi-level quality monitoring, and risk-informed discharge. This framework promotes a paradigm shift in medical radioactive wastewater management from conventional end-of-pipe treatment toward integrated full-chain governance, providing theoretical insights and practical guidance for the standardized, refined, and sustainable management of medical radioactive wastewater in China. Full article

Background: Hospitals are recognized as important point sources of antimicrobials; however, their contributions to antimicrobial contamination at the watershed scale remain poorly understood. Methods: Seasonal monitoring was conducted between December 2024 and May 2026 at two hospitals, a wastewater treatment plant (WWTP), and receiving river waters in the Yodo River Basin, Japan. Seventeen antimicrobials were quantified, and concentration profiles and mass fluxes were integrated to evaluate source contributions. Results: Ampicillin, levofloxacin, azithromycin, clarithromycin, and vancomycin were the predominant antimicrobials. Hospital wastewater was identified as the dominant source of ampicillin and vancomycin, whereas levofloxacin and clarithromycin were largely influenced by diffuse watershed inputs. Several antimicrobials persisted through wastewater treatment and were continuously detected in WWTP effluent and downstream river waters. Conclusions: This watershed-scale assessment demonstrates that antimicrobial contamination is driven by both hospital-derived point sources and broader watershed inputs. These findings provide a scientific basis for integrated hospital wastewater and WWTP management to mitigate environmental antimicrobial resistance (AMR) within the One Health framework. Full article

Hospital wastewater has begun to act as an important source of emerging contaminants, including rare earth elements (REEs), mostly lanthanides, and radiopharmaceutical residues originating from diagnostic and therapeutic nuclear medicine procedures. The increasing use of gadolinium-based contrast agents, lutetium-containing therapeutics, technetium-99m tracers, iodine-131, yttrium-90, and gallium-68 radiopharmaceuticals has raised growing concerns regarding the release of radioactive and metal-containing compounds into aquatic environments. Conventional wastewater treatment plants are often inefficient in removing these contaminants because of their high chemical stability, low environmental concentrations, and complex aqueous speciation. In this context, hybrid nanomaterials containing silver nanoparticles (AgNPs) have attracted increasing interest for both monitoring and remediation applications. AgNP-based systems exhibit unique plasmonic, catalytic, antimicrobial, and sensing properties that can be exploited in adsorption, photocatalysis, membrane filtration, electrochemical detection, and surface-enhanced Raman spectroscopy (SERS). This review critically analyzes recent advances in hospital wastewater treatment and how hybrid nanomaterials containing silver nanoparticles (AgNPs) are emerging. The review places a particular focus on contamination by REEs and radiopharmaceuticals residues, which to date, as far as we know, remains a challenging and understudied aspect, as reflected by limited publications. Full article

Wastewater-based surveillance has emerged as a powerful approach for population-level monitoring of pathogen circulation in a timely and non-invasive manner. In this study, shotgun metagenomic sequencing was applied to wastewater samples collected from a hospital (HP), a university campus (UN), and a wastewater treatment plant (WTP). Viral sequences were taxonomically classified using Kraken2. Specifically, HP samples showed the highest viral richness, followed by WTP and UN samples (HP vs. UN, p = 0.0003; WTP vs. UN, p = 0.0018). Using Jaccard distance, significant differences were observed between WTP and UN (R² = 0.181, p < 0.001), WTP and HP (R² = 0.159, p < 0.001), and UN and HP (R² = 0.223, p < 0.001), and similarly, for Sørensen–Dice dissimilarity: WTP vs. UN (R² = 0.238, p < 0.001), WTP vs. HP (R² = 0.212, p < 0.001), and UN vs. HP (R² = 0.307, p < 0.001). Human-associated viral families were detected across all sources, predominantly Poxviridae, Orthoherpesviridae, Polyomaviridae and Circoviridae. Furthermore, the taxonomic composition of indirectly associated viruses, mainly Anelloviridae and Crassvirales, was examined. Overall, these findings support the potential of wastewater metagenomics as a reliable tool for monitoring viral diversity within environmental and public health contexts, although further research is needed to establish its operational utility for routine surveillance applications within a One Health framework. Full article

Wastewater treatment plants (WWTPs) receive clinically relevant Acinetobacter species originating from hospitals and municipal sewage, yet their role in enhanced biological phosphorus removal (EBPR) remains unclear. This study evaluated the capacity of Acinetobacter spp. to accumulate orthophosphate (P) under conditions simulating the aerobic phase of EBPR and investigated the physiological and molecular determinants of P accumulation. Clinically relevant A. pittii and A. baumannii exhibited comparable growth to the model P-accumulating species A. junii and successfully proliferated in synthetic wastewater. However, A. junii maintained significantly higher P uptake rates, accumulated more intracellular polyP granules, and continued to remove P after entering the stationary phase, whereas P removal by A. pittii and A. baumannii reached a plateau. While A. junii and A. pittii contained a single ppk1 gene, two distinct ppk1 homologues and the corresponding PPK1 isoforms were identified in A. baumannii. Nevertheless, neither ppk1 copy number, ppk1 expression, nor the abundance of key enzymes involved in canonical polyP metabolism explained the enhanced P accumulation capacity of A. junii. Proteomic analyses suggested that continued P uptake in A. junii was associated with physiological adaptations that support the maintenance of cellular fitness during the stationary phase. Consequently, EBPR systems may favour the persistence and proliferation of clinically relevant Acinetobacter spp. without substantially benefiting from their contribution to P removal. Full article

Background: Wastewater systems provide an integrated One Health perspective on antimicrobial resistance but remain uneven globally, with limited data from rapidly urbanizing and highly connected regions such as the Arabian Gulf. Methods: An eight-month prospective study was conducted in Dubai, United Arab Emirates, with monthly sampling from nine community and two hospital nodes and two wastewater treatment plants (WWTP). Samples were analysed using high-throughput quantitative PCR (HT-qPCR; Resistomap, Finland) with a 72-target One Health gene panel. Results: Across the 120 samples analyzed, the number of detected gene targets ranged from 26 to 68 genes, with the highest diversity in hospital wastewater and the lowest in WWTP effluent. Pathogen-associated markers were detected in all sources, with enterococci, Escherichia coli, and Klebsiella pneumoniae predominant. Hospital wastewater showed broader pathogen-associated gene markers, including those linked to Acinetobacter baumannii and Pseudomonas aeruginosa. Antibiotic resistance genes (ARGs) associated with macrolide–lincosamide–streptogramin B, tetracycline, and aminoglycoside resistance were widespread. Community and influent samples were dominated by msrE, tet(M), and aminoglycoside resistance genes, whereas hospital wastewater showed the highest ARG burden, including enrichment of aac(6′)-Ib, qnrS2, bla_GES, bla_TEM, bla_KPC-2, and bla_IMP-1. Several ARGs, including mcr-1, persisted in WWTP effluent. Mobile genetic elements (MGEs) were ubiquitous, with integron-associated markers prominent in WWTP effluent. ARG–MGE network analysis demonstrated extensive co-occurrence, with MGEs as central hubs linking multiple ARGs. Conclusions: Wastewater captures distinct resistome profiles across urban compartments, supporting its role for AMR surveillance. The persistence of ARGs and MGEs in WWTP effluent highlights the potential for environmental dissemination, through reuse of treated wastewater. Full article

We analysed nine Pseudomonas guariconensis-clade genomes from environmental and clinical sources across four continents to test whether carriage of acquired resistance is associated with the acquisition of mobile elements. FA-1, our tick-derived anchor from Hyalomma dromedarii on Saudi camels, sits at 87.52–87.94% ANI to the other genomes on the longest external branch of the core-genome ML phylogeny. In the current NCBI type-strain ANI taxonomy check, FA-1 is conspecific with the recently described Pseudomonas shiyinii type strain ST4 (98.05% ANI). The recently reported Vietnamese hospital-wastewater isolate KNHN1 groups within the sensu stricto clinical clade alongside USA-Nashville and India at 99.7%/99% (SH-aLRT/UFBoot) support. Across the nine genomes, three distinct carbapenemase architectures emerged: Dao (chromosomal KPC-2 + NDM-1 + AFM-5), Ethiopia (chromosomal NDM-1 × 2 + plasmid VIM-4), and Korea (plasmid VIM-2). Dao and Ethiopia chromosomes share a MOBH-family relaxase signal, extending the MOBH marker to the clinical compartment. MBL-positive genomes carried more mobile elements (Dao 55; Ethiopia 22; Korea 16; 16–55 hits) than MBL-negative comparators (0–8 hits), an unadjusted descriptive observation (n = 3 vs. 6). Ethiopia presented an integron-rich chromosomal and plasmid architecture (six structures), while Dao carried IS-bounded transposon islands on the chromosome. Three of four Dao chromosomal ICE predictions and one Ethiopia ICE prediction lay 27–50 kb from IS-bounded carbapenemase loci; a fourth Dao ICE was standalone and the major Ethiopia NDM-1 + OXA-10 cassette lacked an adjacent complete ICE prediction, indicating descriptive ICE-cassette proximity rather than functionally demonstrated mobility. Together, these findings are consistent with mobile-element acquisition as a plausible route for the emergence of clinical resistance within this clade, with environmental relatives retaining empty insertion sites at the AMR-cassette locus. Full article

Ketoprofen (KET) is a non-steroidal anti-inflammatory drug frequently detected in surface waters and effluents, with the potential to impact trophic base organisms. This study evaluated the toxicity of KET, in its active pharmaceutical ingredient (API) form and in four commercial formulations (KET-1, KET-2, KET-3, and KET-4), on two freshwater species: the cyanobacterium Microcystis novacekii and the microalga Chlorella vulgaris. Cell growth assays, performed under acute (4 days) and chronic (14 days) conditions, showed that the API KET was the most toxic compound, especially for M. novacekii, with a chronic EC50 of 1.35 mg/L. The commercial formulations presented distinct toxicity profiles, suggesting the influence of excipients and synergistic or antagonistic interactions. For C. vulgaris, low acute toxicity was observed, with increased chronic effects at high concentrations and possible hormetic response at low doses. Risk quotient (RQ) calculations, based on environmental concentrations of KET, indicated low risk in surface and drinking water, but high risk in untreated hospital and wastewater treatment plant effluents, especially for M. novacekii. The results show that the complete formulation, exposure time, and target species are critical factors in the ecotoxicological risk assessment of pharmaceuticals in freshwater environments. Full article

Background: Human hospitals and veterinary centres are hotspots for resistant microbes and plasmids, and metagenomic sequencing offers an agnostic insight into microbiomes, resistomes, and mobilomes, informing strategies for reducing AMR spread. Methods: Environmental samples, including wastewater and surface swabs, were taken from a tertiary human hospital ward (36 samples) and a companion animal veterinary hospital (48 samples) in London. Whole DNA was extracted and metagenomic sequencing undertaken using Oxford Nanopore Technologies’ MinION. Data were analyzed for microbiomes, resistomes and mobilomes and compared. Results: Microbial diversity analyses highlight higher richness across human hospital (HH) environmental samples, but more evenness in veterinary hospital (VH) environmental samples. Diversity showed distinct microbial communities in the HH and VH samples. There were significantly more total antimicrobial resistance gene (ARG) types (p < 0.0001) in the environmental HH samples compared with the environmental VH samples. There was a significantly higher mean number of Enterobacteriales plasmid types (p ≤ 0.0001) in the HH samples. There were significantly more total Gram-Positive plasmid types (p ≤ 0.0001) in the VH samples. Discussion: This research highlights the presence of human and animal pathogens, ARGs and mobile genetic elements in clinical environments, underscoring the importance of multisectoral surveillance. Integrating taxonomic, resistome, and mobilome analyses provides a better understanding of the potential for AMR dissemination at the human–animal–environment interface. This provides insights relevant for the development of targeted surveillance and mitigation strategies within a OH framework. Full article

Cephalexin is a widely used antibiotic frequently detected in hospital wastewater and aquatic environments near pharmaceutical facilities, where its persistence contributes to the spread of antibiotic resistance. Mechanically driven advanced oxidation processes, including piezocatalysis and tribocatalysis, represent sustainable alternatives for pollutant removal because they operate without external light or heat sources. In this study, ZnO catalysts with controlled morphologies were synthesized via sol–gel and mechanochemical methods using different solvents and activation times (1 and 5 h). The influence of structural characteristics, surface area, and friction conditions on catalytic performance was systematically evaluated. The results demonstrated that tribocatalytic efficiency strongly depends on stirring rate and reactor material, with PTFE systems exhibiting superior performance. Mechanochemically activated ZnO (1 h) showed the highest degradation efficiency due to optimized defect density and surface accessibility. All catalysts exhibited high stability, while radical scavenging experiments identified superoxide radicals as the primary reactive species in the degradation process. Full article

Hospital wastewater treatment efficacy is conventionally assessed by total antibiotic resistance gene (ARG) abundance; however, whether this metric accurately reflects biosafety risk remains poorly defined. Using a one-year longitudinal metagenomic survey (bimonthly sampling; n = 18 per group), we simultaneously profiled the resistome, virulome, and mobilome of hospital wastewater influent and effluent; stratified functional gene abundances by genomic origin; quantified ARG–mobile genetic element (MGE) colocalization; and characterized multicategory gene cocarriage across the 15 most abundant pathogenic species. Although the abundance of total strict ARGs decreased significantly in the effluent (p = 0.038), the abundances of metal resistance genes and virulence factors increased concurrently (both p < 0.01), and 8 of the 20 ARG subtypes were enriched rather than removed. This decline was driven exclusively by a reduction in the number of plasmid-encoded ARGs (p < 0.001), whereas genes encoding chromosomal virulence factors, metal resistance genes, biocide resistance genes, and MGEs were significantly enriched in the effluent (all p < 0.05). The normalized ARG–MGE colocalization rate was significantly greater in the effluent (p = 0.028), with a concurrent shift toward transposase-mediated chromosomal mobilization. Pathogen-associated metagenomic assemblies of clinically relevant species exhibited synchronous multicategory resistance coenrichment in the effluent, which is consistent with coselection under antibiotic, biocide, and metal pressures. Total ARG abundance is fundamentally decoupled from biosafety risk in treated hospital wastewater, warranting integrated surveillance beyond ARG-centric metrics. Full article

Industrial and municipal wastewater may contain substances that inhibit biological processes in wastewater treatment plants (WWTPs), posing risks to operational stability and environmental protection. The aim of this study is to evaluate the practical suitability of the ISO 8192:2007 respiration inhibition test for assessing the toxicity of wastewater. Nitrified activated sludge from a municipal WWTP was used to analyze wastewater from three industrial companies, wastewater from several discharge locations at a hospital, and WWTP influent. Oxygen consumption and inhibition were determined at sample-specific dilution levels and the reference substance 3,5-dichlorophenol. Two samples from the dental department of the hospital showed toxic effects on activated sludge respiration (inhibition > 50%), while no toxic effects were observed in the remaining samples. Several samples exhibited stimulatory effects (inhibition < 0%), indicating the presence of readily biodegradable organic matter. However, inhibitory effects (0–50% inhibition) were detected in individual wastewater samples at higher concentrations. This demonstrates that the method can detect toxicological changes in wastewater and is suitable for routine monitoring and early warning in WWTPs. Full article