A comprehensive understanding of fecal pollution dynamics and associated antibiotic resistance is critical for effective water quality management in coastal watersheds exposed to strong hydrological variability. This study aimed to identify the relative contribution of human and animal fecal sources, assess the spatial and temporal distribution of contamination, and evaluate the occurrence of selected antibiotic resistance genes (ARGs) across a Mediterranean land-sea continuum (central Adriatic Sea, Italy) under contrasting rainfall conditions. Surface water and sediment samples were collected during the bathing season and analyzed using host-associated microbial source tracking (MST) markers and selected ARGs. Human fecal contamination was the dominant source, as indicated by the consistent detection of HF183, which significantly increased during moderate and extreme rainfall events, indicating inputs from runoff and sewer overflows. The presence of human adenovirus (HAdV) further supported sewage-derived contamination, whereas animal-associated markers showed lower detection frequencies and more heterogeneous spatial patterns. ARGs, including tetracycline resistance genes tetM, were widely detected, with generally higher concentrations at freshwater sites. While ARG distribution was influenced by hydrological variability, tetM showed lower temporal variability and remained relatively abundant under drought conditions, suggesting longer-term environmental persistence. Rainfall emerged as a major driver shaping marker distribution, with water showing high temporal variability and sediments acting as secondary reservoirs enriched during heavy rainfall events. These findings provide relevant insights for improving water quality strategies and support targeted management actions to mitigate fecal pollution in Mediterranean coastal systems.

Traditional sediment risk assessments often rely on fixed-duration dose-response end points, which overlook how exposure conditions and organismal response interact over time. Toxicokinetic-toxicodynamic (TKTD) models address this by linking external exposure, internal concentration, and effects, but their application to sediments has been limited by the lack of suitable tracing methods to generate high-quality kinetic data. Here, we developed a novel stable isotope tracing approach tailored for sediment TKTD studies: prelabeling clams with stable 65Cu in water prior to Cu-amended sediment exposure. By simultaneously tracking 65Cu elimination and ambient Cu uptake, we successfully established a sediment TKTD model integrating bioaccumulation with toxicity, measured by clam survival across a wide range of Cu bioavailability driven by speciation differences. The model revealed that the clam Ruditapes philippinarum's Cu elimination and tolerance capability were consistent across exposure conditions, indicating species-specific physiological traits. Cu uptake followed a saturation-type Michaelis-Menten relationship with bioavailable Cu. From these kinetics, we derived mechanistic bioavailability benchmarks (DGT-Cu based LC50-chronic = 42 μg L-1 and no-effect concentration (NECDGT) = 34 μg L-1) as chronic thresholds applicable to risk assessment. Overall, this study demonstrates TKTD modeling in sediments using stable isotope tracing, advancing process-based ecological risk assessments and providing a transferable framework for evaluating contaminant bioavailability in estuarine ecosystems.

Ecological risk assessment often requires extrapolation from short-term laboratory-derived effects data to predict long-term ecological impacts of pollution exposure. This study developed a mechanistic toxicokinetic-toxicodynamic (TKTD) modeling framework to derive acute-to-chronic ratios (ACRs) for the benthic clam Ruditapes philippinarum exposed to sediment-associated Cu. To facilitate model development in the sediment context, we derived physiological parameters (k e, C IT, k k) using aqueous toxicity tests and used diffusive gradients in thin-films (DGT) measurements to represent Cu bioavailability in sediments. The sediment TKTD model accurately predicted Cu accumulation in clam tissues and adequately predicted toxicity, with a 10% deviation from observed effects. Using model-predicted 7-day LC50 and no-effect concentration, an ACR of 17 was determined for Cu-induced clam mortality. The framework was then applied to derive ACRs for other contaminants using literature-derived aqueous TKTD parameters, including cadmium (ACRCd: 11-87) and nanoplastic particles (ACRNPs: 1.9-69). The new approach was also effective for elucidating how environmental variables (e.g., salinity, nanoplastic size) influence ACR values, thus offering insight which may be difficult to achieve by traditional empirical approaches. The study demonstrates the utility of TKTD modeling as a transparent and reproducible mechanistic method for acute-to-chronic extrapolation of toxicity as used for risk assessment applications.

Abstract Wastewater surveillance (WS) offers a non-invasive means of tracking population-level circulation of infectious agents, including viruses linked to cancer. This study provides the first Australian assessment of oncogenic viruses in municipal wastewater by screening 76 influent samples collected over four months from six wastewater treatment plants in Southeast Queensland, Australia. Ten gene targets representing seven oncogenic viruses— Epstein–Barr virus (EBV), hepatitis B virus (HBV), hepatitis C virus (HCV), human herpesvirus 8 (HHV-8), human papillomavirus 16 and 18 (HPV-16 and 18), human T-lymphotropic virus type 1 (HTLV-1), and Merkel cell polyomavirus (MCPyV)—were analysed using PCR-based methods. All viruses were detected in wastewater at least once, though with substantial variation in frequency. MCPyV was the most frequently detected virus, appearing in 97.3% of samples with concentrations ranging from 3.09-3.85 log₁₀ gene copies (GC)/50 mL, indicating widespread population exposure. HBV (26.3%) and EBV (15.8%) were detected intermittently across multiple catchments, while HPV-16/18, HHV-8, HTLV-1, and HCV were detected at the lowest frequencies (<8%). This study reports the first baseline dataset for oncogenic viruses in Australian wastewater. More broadly, positive detection of all targeted oncogenic viruses—including those associated with low-prevalence infections—in wastewater demonstrates the potential of WS to complement existing cancer surveillance systems in tracking community-level circulation of these infectious agents. Graphical abstract Highlights Seven oncogenic viruses were screened in influent wastewater from six WWTPs. MCPyV was detected with the highest frequency, in 97.3% of samples. HBV and EBV were detected intermittently across multiple WWTP catchments. HPV, HHV-8, HTLV-1 and HCV were detected at the lowest frequencies. Wastewater surveillance shows promise for monitoring oncogenic viruses.

This study assessed the accuracy, field suitability, and cost-effectiveness of colorimetric LAMP (c-LAMP) assays using six heating instruments: Electric Kettle, Water Bath, Heating Block, miniPCR, Thermocycler, and Genie® III. Bacteroides HF183 (HF183), SARS-CoV-2, and Aichi virus A (AiV-A) were tested using control materials and wastewater samples, comparing cLAMP with qPCR/RT-qPCR detection. qPCR/RT-qPCR reliably detected HF183 and AiV-A genetic fragments at dilutions as low as 1 × 10-5 pg/μL, corresponding to 1.24 and 1.49 log10 GC/reaction. cLAMP/RT-cLAMP detected these fragments at 1 × 10-4 pg/μL (2.28 and 2.63 log10 GC/reaction), though Electric Kettle, miniPCR, and Genie® III occasionally produced false negatives. RT-qPCR reliably detected SARS-CoV-2 fragments at 1 × 100 GC/μL (1.86 log10 GC/reaction), with cLAMP/RT-cLAMP performing similarly across most instruments except Thermocycler. No significant differences (p > 0.05) were observed among instruments, though inconsistencies appeared at lower concentrations. The findings offer valuable insights into heating instrument performance for cLAMP/RT-cLAMP assays, guiding their application in wastewater-based pathogen detection.

The performance of two membrane-based passive samplers (Torpedo and MSTFlow) in quantifying sewage (Carjivirus, plant pepper mild mottle virus [PMMoV], tomato brown rugose fruit virus [ToBRFV]) and avian (Helicobacter spp. GFD marker) fecal pollution markers in an urban riverine environment over a 72-h deployment was evaluated using a first-order kinetic model to characterize their microbial adsorption characteristics. Results were compared with those from parallel composite and time-weighted autosampling. Passive sampler accumulation exhibited an initial lag phase (0 to 8 h for viruses) and reached equilibrium within 16 h of initial deployment, except for GFD. Sampling rates were highest for PMMoV (6.29 and 5.11 mL/h) for MSTFlow and Torpedo samplers respectively, followed by Carjivirus (4.63 and 3.63 mL/h), ToBRFV (2.17 and 1.22 mL/h) and GFD (0.68 mL/h in Torpedo sampler). At equilibrium, both sampler configurations accumulated 23 ->220 times the amount of target gene copies in each mL of grab water samples, depending on sampler and virus. These findings highlight passive sampling as a promising, sensitive, cost-effective, and low-maintenance alternative for continuous microbial water quality monitoring in aquatic environments. Overall, this study advances the understanding of passive sampling kinetics and supports their broader adoption for tracking fecal pollution in environmental waters.

Japanese encephalitis virus (JEV) poses a significant public health threat in Asia, the Western Pacific, and Australia, necessitating robust surveillance and management strategies. This study evaluates three RT-qPCR assays (Universal JEV, ACDP JEV G4, and VIDRL2 JEV G4) for detecting JEV in piggery wastewater, a promising approach for early outbreak detection. We assessed assay limit of detection (ALOD), process limit of detection (PLOD), and recovery efficiency using gamma-irradiated JEV seeded into wastewater samples, alongside field-derived samples from an Australian piggery. The ACDP JEV G4 assay demonstrated superior sensitivity, with an ALOD of 2.20-5.70 copies/reaction and PLOD of 72-282 copies/10 mL of piggery wastewater, detecting JEV in 23/30 field samples compared to 17/30 for Universal JEV and 0/30 for VIDRL2 JEV G4 assays. Recovery efficiencies varied, with ACDP JEV G4 showing consistent performance (14.9-26.6 %) across concentrations. McNemar's test confirmed ACDP JEV G4's higher sensitivity (p < 0.05). Based on the results obtained in this study, the ACDP JEV G4 assay is recommended for wastewater surveillance in genotype 4 regions, with a dual-assay approach suggested for broader genotype coverage. These findings enhance JEV surveillance strategies, supporting early detection and control.

Tropical estuaries are hyper-diverse ecosystems, hosting essential habitats for freshwater, euryhaline, and marine life. Understanding how biological communities are distributed in these systems has long been a challenge because of their inherent dynamic nature and the diversity of interacting natural pressures and anthropogenic stressors they are subjected to. In addition, most studies focus on a single taxonomic group, hindering a comprehensive understanding of the interactive effects of natural and human-driven environmental variations on the different components of tropical estuarian biodiversity. In this study, we used environmental DNA (eDNA) metabarcoding to examine the structure of multi-taxonomic communities, from diatoms to fish, and their relationships with environmental drivers in three differentially impacted locations facing the Great Barrier Reef in Central Queensland (Australia). We first demonstrated that eDNA signals from sediment and water matrices provide complementary information and that both should be monitored for a more holistic understanding of community trajectories in anthropogenically impacted aquatic environments. We also observed that, independently of the taxonomic group considered, communities were primarily structured by the ecological conditions of the estuary. A within-estuary differentiation along an upstream-downstream gradient was detected but only for small-bodied organisms, which further adds credence to eDNA approaches as an ecologically relevant tool for monitoring fine-scale biodiversity patterns even in profoundly dynamic environments. Finally, the different communities exhibited contrasting response patterns, in terms of diversity, composition, and uniqueness, to the anthropogenic gradient. Hence, our findings emphasize the need for multi-taxonomic assessments, for which eDNA is well suited, to better understand the impacts of multiple stressors on biodiversity and thereby assist decision makers in the protection and management of tropical estuaries.

Sediment quality assessments often rely on equilibrium partitioning theory to predict dissolved contaminant concentration in porewaters. Yet, the theory assumes static conditions and may overlook the influence of hydrodynamic forces on contaminant mobility, particularly in low-permeability sediments. In this study, hydrodynamic microcosms simulating shear stresses of 0.02-0.28 Pa were used to investigate porewater metal concentrations over 32 days. As shear stress increased, porewater concentrations of redox-sensitive Fe and Mn decreased, reflecting enhanced oxidation. In contrast, Ni, Cu, and Cd concentrations increased with rising shear stress but were ultimately constrained by solubility limits. Zn and Pb remained relatively stable, reflecting limited remobilization likely due to rapid scavenging. To account for the uncertainty induced by hydrodynamic variability, we developed a quantitative framework integrating site-specific shear stress into risk assessments. Monte Carlo simulations estimated the uncertainty ranges of metal concentrations, with interquartile ranges of 2.4- to 5.4-fold for Cu, 1.9- to 2.9-fold for Ni, and 1.1- to 2.3-fold for Cd, suggesting moderate hydrodynamic influence on Cu risk and relatively low impact on Cd, Ni, Zn, and Pb. These findings improve understanding of contaminant behavior in dynamic aquatic environments, providing practical insights for refining risk assessment frameworks and enhancing environmental management strategies.

Japanese encephalitis virus (JEV), a mosquito-borne orthoflavivirus, raises concerns about its seasonal re-emergence. Pigs are a major amplifying host and JEV infection can manifest as significant reproductive disease and losses, necessitating robust surveillance. This study evaluated effluent surveillance for early JEV detection in piggery effluent from a Victorian farm between December 2024 and March 2025. Effluent samples were tested using JEV-specific real-time reverse transcription (RT)-PCR, with positive detections found on four separate sampling days, despite an absence of clinical signs in livestock through the testing period. Subsequent veterinary investigations for JEV in litters born on 17/05/2025 (suspect cases only) aligned with a positive effluent sample collected during the estimated JEV infection exposure periods of the sows. With the single clinically confirmed JEV case (which farrowed on 1/06/2025) collection of the same positive effluent sample fell just outside, but near, the estimated exposure period for the affected sow. These findings highlight ability of effluent monitoring to detect JEV infection 2 to 4 months before clinical manifestations present, offering potential for a non-invasive, herd-level early warning system. Intermittent detections may suggest limitations in grab sampling and low viral loads in effluent samples. Integrating effluent surveillance with veterinary clinical testing of litters suspected of being exposed to JEV or during high-risk periods could enhance JEV management in Australia’s enzootic regions, supporting One Health strategies. ### Competing Interest Statement The authors have declared no competing interest.

Long-haul flight aircraft wastewater may serve as a representative microbial footprint, often of mixed country origin, offering valuable insight into the movement of pathogens and antimicrobial resistance (AMR) on a global scale. Herein, we present a proof-of-concept for aircraft-based surveillance of AMR by investigating lavatory wastewater samples from 44 repatriation flights to Australia departing from nine countries. Profiles of pathogens including ESKAPE pathogens (Salmonella spp., Mycobacterium spp., Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa) and antibiotic resistance genes (ARGs) (aph(3')-IIIa, blaNDM-1, blaCTX_M-1, blaKPC, ermB, qnrS, sul1, tetM, and vanA) were investigated along with traditional fecal indicator bacteria (Escherichia coli and Enterococcus spp.) and fecal/urine marker genes (Bacteroides HF183, Carjivirus, human polyomavirus, and a cryptic plasmid pBI143) using quantitative PCR (qPCR). Two fecal indicator bacteria (FIB) and four human fecal/urine marker genes were detected in all aircraft wastewater samples. Detection rates for ESKAPE pathogens ranged from 6.8% (S. aureus) to 84.1% (K. pneumoniae). Of all ARG targets, aph(3')-IIIa, ermB, qnrS, sul1, and tetM were detected in all wastewater samples, whereas blaKPC and vanA were not detected in any of the samples. Results reflected geographic differences in ARG abundance originating from departure countries/continents and suggested a potential risk of importing ARGs that might be rare in local wastewater systems. The loss of nucleic acid targets was less than 10% over a 24 h incubation in the presence of disinfectants, suggesting that nucleic acids are resilient enough to persist in aircraft wastewater over the maximum duration of a flight.IMPORTANCEIn the context of international connectedness, aircraft-based wastewater surveillance should be viewed as a beyond-national tool to enhance global AMR management and foster international cooperation.

Highlights• Long-term ecosystem impacts of open-loop EGCS washwater discharges in a harbour port modelled and evaluated.• Copper identified as a limiting contaminant.• Safe dilutions of washwaters calculated from ratios of discharge data to guideline values.• Shipping washwater contributions to Sydney harbour waters and sediments are negligible

Climate change is increasing wildfire intensity, introducing new risks to estuarine systems. However, the impacts of wildfires on estuaries and their recovery remain poorly understood. To address this, we conducted a large-scale longitudinal survey investigating sediment quality across river-to-estuary systems affected by fire. We measured concentrations of carbon, nutrients, chlorophyll-a, and silt content in sediment at 90 sites across six waterways with varying extents of burnt catchment area. Pyrogenic carbon (PyC), measured using mid-infrared spectroscopy, proved a reliable indicator of fire impacts, whereas nutrients levels varied more with seasonal changes. PyC concentrations declined significantly over 12 months post-fire, halving in most fire-affected estuaries. However, in one catchment with 92 % burnt area, there was no reduction in the concentration of PyC within 12 months, suggesting prolonged impact. Fire location and burnt area extent influenced temporal PyC trends. This study is the first to assess sediment quality over time in the upper, middle and lower estuarine sections following wildfires. Our findings are important for managing coastal areas amid increasing wildfire frequency and severity. Using PyC as a stable indicator of fire impact can improve monitoring and guide recovery efforts, helping safeguard estuarine health and function.

This study investigated the effects of various sample concentration and extraction workflows on the alpha and beta diversities of bacterial communities in influent wastewater samples from three wastewater treatment plants (WWTPs). The workflows that incorporated DNeasy Blood & Tissue (DBT) Kit consistently demonstrated the highest alpha diversity metrics (% total observed in study), indicating superior efficacy in capturing microbial diversity. In contrast, workflows that included the DNeasy PowerSoil Pro (DPP) Kit exhibited the lowest alpha diversity (% total), likely due to suboptimal lysis efficiency. Beta-diversity analysis revealed significant differences in microbial community composition of wastewater samples across the WWTPs, driven by workflows and temporal variations. Notably, Proteobacteria was the dominant phylum, while variations in the abundance of Firmicutes and Actinobacteria were also observed, underscoring the methodological influence on community profiling. The study also revealed significant variations in the Firmicutes/Bacteroidetes (F/B) ratio across workflows and WWTP samples, suggesting potential correlations with local health demographics. Our findings emphasize the critical role that sample concentration and extraction workflows play in bacterial community analyses, and that high variability of results between workflows may often prevent meaningful data comparison. Quantifying and reporting metric for the level of bacterial 16S rRNA capture together with details of the sample concentration and extraction protocols will improve comparison of diverse bacterial populations in wastewater environments. This research advances the understanding of bacterial dynamics in WWTP influent samples, enhancing wastewater surveillance efforts.

Japanese encephalitis virus (JEV) is an emerging public health and biosecurity concern in Australia, with recent human cases and detections in mosquitoes and pigs across multiple states highlighting the risk to susceptible human and animal populations. While traditional surveillance methods such as mosquito trapping, sentinel chicken programs, and direct testing of pig specimens remain essential, monitoring effluents offers a valuable complementary approach for detecting infections within livestock herds. This study presents the first evidence of JEV in Australian piggery effluents and environmental waters, demonstrating the feasibility of effluent and environmental water surveillance for JEV monitoring. Effluent and environmental samples from multiple piggery sites were analyzed using real-time reverse transcription polymerase chain reaction, revealing the presence of JEV genetic fragments in solid and liquid fractions of effluents at three farms, with corresponding veterinary cases in some herds. Viral RNA was detected more frequently in the solid fraction of effluent samples, aligning with previous findings on the partitioning behavior of mosquito-borne viruses. The detection of JEV in environmental water from an excavated area highlights the potential for transmission via mosquito vectors. These findings demonstrate the value of effluent monitoring as an additional tool for JEV surveillance in piggery settings, supporting potential early warning systems and mitigation strategies. Integrating effluent-based monitoring with traditional surveillance approaches could improve livestock-industry-related disease detection, risk assessments, and response efforts for human and animal health in both endemic regions and areas where livestock diseases are emerging. Wastewater and effluent surveillance may have important applications for the management of a wide range of emerging animal diseases.IMPORTANCEThis study presents the first evidence of JEV detection in Australian piggery effluents, establishing effluent surveillance as a valuable complementary tool for monitoring viral pathogens in animal herds. Our findings support the integration of effluent monitoring with traditional surveillance systems to improve early warning capabilities, enhance biosecurity, and mitigate risks to both human and animal health.

Understanding the toxicokinetics of metal bioaccumulation in natural environmental conditions is crucial for translating biomonitoring data into accurate environmental risk assessments. However, the lack of effective in situ tracing techniques has limited our ability to effectively assess and predict metal bioaccumulation within the environment. We developed a novel isotope tracing approach that combines laboratory isotope-labeling with field transplantation of organisms. Mussels (Perna viridis and Mytella strigata) were labeled with enriched stable isotopes (61Ni, 65Cu, 68Zn, 107Ag, 113Cd, and 206Pb) and then transplanted in an estuary. Temporal changes in isotopic concentrations were modeled using a one-compartment toxicokinetic model. In-situ metal efflux rate constants (kefield) were found 1.4-12 times greater than the laboratory-derived values (kelab) for different metals, indicating a faster metal processing rate in the field. Metal influx through aqueous and dietary routes was modeled using non-labeled metal concentrations. The in-situ aqueous uptake rate constants (kufield) closely aligned with laboratory values (kulab), with a bias of 20 % or less, while the in-situ dietary uptake rate constants kffield, determined indirectly, exhibited higher uncertainty. Our model predicted maximum safe concentrations of Cd and Pb in water for cultured mussels (P. viridis) at 0.9 and 0.03 µg L-1, which are lower than the China "Water Quality Standards for Fisheries" for Pb (50 µg L-1) and Cd (5 µg L-1). This study extends the utility of stable isotope tracing beyond laboratory conditions, improving metal biomonitoring data interpretation for risk assessments in complex environments.

This study establishes site -specific risk -based threshold (RBT) concentrations for sewage -associated markers, including Bacteroides HF183 (HF183), Lachnospiraceae Lachno3 (Lachno3), cross -assembly phage (CrAssphage), and pepper mild mottle virus (PMMoV), utilizing quantitative microbial risk assessment (QMRA) for recreational estuarine waters (EW). The QMRA model calculates a RBT concentration corresponding to a selected target illness risk for ingestion of EW contaminated with untreated sewage. RBT concentrations were estimated considering site -specific decay rates and concentrations of markers and reference pathogen (human norovirus; HNoV), aiding in the identification of high -risk days during the swimming season. Results indicated varying RBT concentrations for fresh (Day 0) and aged (Days 1 to 10) sewage contamination scenarios over 10 days. HF183 exhibited the highest RBT concentration (26,600 gene copis (GC)/100 mL) initially but decreased rapidly with aging (2570 to 3120 GC/100 mL on Day 10) depending on the decay rates, while Lachno3 and CrAssphage remained relatively stable. PMMoV, despite lower initial RBT (3920 GC/100 mL), exhibited increased RBT (4700 to 6440 GC/100 mL) with aging due to its slower decay rate compared to HNoV. Sensitivity analysis revealed HNoV concentrations as the most influential parameter. Comparison of marker concentrations in estuarine locations with RBT concentrations showed instances of marker exceedance, suggesting days of potential higher risks. The observed discrepancies between bacterial and viral marker concentrations in EW highlight the need for optimized sample concentration method and simultaneous measurement of multiple markers for enhanced risk predictions. Future research will explore the utility of multiple markers in risk management. Overall, this study contributes to better understanding human health risks in recreational waters, aiding regulators, and water quality managers in effective decision -making for risk prioritization and mitigation strategies.

Agricultural run-off in Australia’s Mackay-Whitsunday region is a major source of nutrient and pesticide pollution to coastal and inshore ecosystems of the Great Barrier Reef. While the effects of run-off are well documented for the region’s coral and seagrass habitats, the ecological impacts on estuaries, the direct recipients of run-off, are less known. This is particularly true for fish communities, which are shaped by the physico-chemical properties of coastal waterways that vary greatly in tropical regions. To address this knowledge gap, we used environmental DNA (eDNA) metabarcoding to examine fish assemblages at four locations (three estuaries and a harbour) subjected to varying levels of agricultural run-off during a wet and dry season. Pesticide and nutrient concentrations were markedly elevated during the sampled wet season with the influx of freshwater and agricultural run-off. Fish taxa richness significantly decreased in all three estuaries (F = 164.73, P = <0.001), along with pronounced changes in community composition (F = 46.68, P = 0.001) associated with environmental variables (largely salinity: 27.48% contribution to total variance). In contrast, the nearby Mackay Harbour exhibited a far more stable community structure, with no marked changes in fish assemblages observed between the sampled seasons. Among the four sampled locations, variation in fish community composition was more pronounced within the wet season (F = 2.5, P = 0.001). Notably, variation in the wet season was significantly correlated with agricultural contaminants (phosphorus: 6.25%, pesticides: 5.22%) alongside environmental variables (salinity: 5.61%, DOC: 5.57%). Historically contaminated and relatively unimpacted estuaries each demonstrated distinct fish communities, reflecting their associated catchment use. Our findings emphasise that while seasonal effects play a key role in shaping the community structure of fish in this region, agricultural contaminants are also important contributors in estuarine systems.

Sediments are an integral component of aquatic systems, linking multiple water uses, functions, and services. Contamination of sediments by chemicals is a worldwide problem, with many jurisdictions trying to prevent future pollution (prospective) and manage existing contamination (retrospective). The present review assesses the implementation of sediment toxicity testing in environmental regulations globally. Currently, the incorporation of sediment toxicity testing in regulations is most common in the European Union (EU), North America, and Australasian regions, with some expansion in Asia and non-EU Europe. Employing sediment toxicity testing in prospective assessments (i.e., before chemicals are allowed on the market) is most advanced and harmonized with pesticides. In the retrospective assessment of environmental risks (i.e., chemicals already contaminating sediments), regulatory sediment toxicity testing practices are applied inconsistently on the global scale. International harmonization of sediment toxicity tests is considered an asset and has been successful through the widespread adoption and deployment of Organisation for Economic Co-operation and Development guidelines. On the other hand, retrospective sediment assessments benefit from incorporating regional species and protocols. Currently used toxicity testing species are diverse, with temperate species being applied most often, whereas test protocols are insufficiently flexible to appropriately address the range of environmental contaminants, including nanomaterials, highly hydrophobic contaminants, and ionized chemicals. The ever-increasing and -changing pressures placed on aquatic resources are a challenge for protection and management efforts, calling for continuous sediment toxicity test method improvement to insure effective use in regulatory frameworks. Future developments should focus on including more subtle and specific toxicity endpoints (e.g., incorporating bioavailability-based in vitro tests) and genomic techniques, extending sediment toxicity testing from single to multispecies approaches, and providing a better link with ecological protection goals. Environ Toxicol Chem 2024;43:1697-1716. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Wastewater surveillance has evolved into a powerful tool for monitoring public health-relevant analytes. Recent applications in tracking severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection highlight its potential. Beyond humans, it can be extended to livestock settings where there is increasing demand for livestock products, posing risks of disease emergence. Wastewater surveillance may offer non-invasive, cost-effective means to detect potential outbreaks among animals. This approach aligns with the "One Health" paradigm, emphasizing the interconnectedness of animal, human, and ecosystem health. By monitoring viruses in livestock wastewater, early detection, prevention, and control strategies can be employed, safeguarding both animal and human health, economic stability, and international trade. This integrated "One Health" approach enhances collaboration and a comprehensive understanding of disease dynamics, supporting proactive measures in the Anthropocene era where animal and human diseases are on the rise.