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Graphene oxide (GO) was used as sorbent in dispersive solid phase extraction (DSPE) to enrich and extract some triazine herbicides from environmental water samples. It can form dispersed colloids in aqueous phase and provides rich functional groups for the formation of hydrogen bonding or π–π electrostatic interaction with benzene ring organic compounds containing oxygen and nitrogen functional groups. GO was synthesised by modified Hummers method and characterised with Fourier transform infrared (FT-IR) spectroscopy. As complete collection of GO after adsorption process is difficult task, in this established salt-assisted (SA)-GO-DSPE method, it was found to be aggregated and centrifuged in the presence of NaCl. The optimum value for main parameters that influenced extraction efficiency were investigated. Under the optimised conditions, low limits of detection (LODs) (0.12–0.80 ng mL −1), limits of quantification (LOQ) (0.4–2.68 ng mL −1), and good extraction recoveries (69.06–95.53%) were obtained for simultaneous extraction of simazine (SIZ), atrazine (ATZ), propazine (PRZ)) and prometryn (PRN). The relative standard deviations (RSD) of intraday (n = 6) and interday (n = 9) precisions were 2.54 to 5.84% and 4.38 to 8.56%, respectively. At the end, the applicability of the method was evaluated and target analytes were not detected in real samples. The proposed method is environment friendly and promising for trace analysis of pesticides including the target herbicides in environmental water samples. [ABSTRACT FROM AUTHOR]

Highly porous biomass-derived activated carbon was prepared by carbonisation of cherry laurel (Prunus laurocerasus L.) stone followed by chemical activation with zinc chloride (ZnCl2) at 700°C. The resulting activated carbon was magnetised using a thermal process. The physicochemical properties of the magnetic activated carbon (AC/Fe3O4) were characterised by N2 adsorption-desorption, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and vibrating sample magnetometer. The magnetic material exhibited a high specific surface area of 959 m2/g and a maximal saturation magnetisation of 28.5 emu/g. The AC/Fe3O4 was then used as an adsorbent for the magnetic solid-phase extraction of target herbicides (hexazinone, propachlor and prometryn) from environmental water samples followed by high performance liquid chromatography-ultraviolet detection. After optimising the main parameters in the extraction procedure, the extraction recoveries and preconcentration factors in the ranges of 71–84% and 18–21 were obtained, respectively. Good linearities were achieved with the coefficients of determination ranging from 0.9978 to 0.9997. The intra- and inter-day relative standard deviations were less than 5.2%. Limits of detection were obtained between 0.05 and 0.28 µg/L. Finally, the proposed method was applied for the determination of the target herbicides in the environmental waters and satisfied recoveries between 71 and 101% were obtained from spiked samples. [ABSTRACT FROM AUTHOR]

Caesium, strontium, and iodine radionuclides are produced from uranium fission and they are easily soluble in water through accidents or leakages, such as those occurred at Chernobyl, Three Mile Island, and Fukushima. Thus, developing an economical and effective process for removing these radioisotopes from real water is a progressively important issue. Hence, adsorption of 137Cs, 85Sr, and 131I radionuclides was achieved using a solid waste adsorbent. The solid waste adsorbent is granular activated carbon (GAC) gained from the wasted household water filters. The gained data illustrated that the percentages of uptake for 137Cs, 85Sr, and 131I were 87.6, 85.6, and 82.7%, respectively. Application of GAC for the decontamination of real water as groundwater, river water, tap water, and seawater was achieved. The findings revealed that GAC has the ability to be employed effectively as a hopeful material for the decontamination of radioactive 137Cs, 85Sr, and 131I from the environmental water. [ABSTRACT FROM AUTHOR]

Waterbirds are highly mobile and have the ability to respond to environmental conditions opportunistically at multiple scales. Mobility is particularly crucial for aggregate‐nesting species dependent on breeding habitat in arid and semi‐arid wetlands, which can be ephemeral and unpredictable. We aimed to address knowledge gaps about movement routes for aggregate‐nesting nomadic waterbird species by tracking them in numbers sufficient to make robust assessment of their movement patterns. We hypothesised that analysis of long‐distance movements would identify common routes with consistent environmental features that would be useful as context for conservation management. We used GPS satellite telemetry to track the movements of 73 straw‐necked ibis (Threskiornis spinicollis) and 42 royal spoonbills (Platalea regia) over 7 years (2016‐2023). We used these data to identify long‐distance movements and to demarcate and characterise movement routes. We identified common routes used by both species, including a 'flyway' over 2000 km long, spanning Australia's Murray–Darling Basin from the south‐west to the north‐east. This flyway connects important breeding sites and is characterised by flat, open/unforested areas with low elevations of < 350 m and mid to high rainfall. The flyway corresponds to an area west of Australia's Great Dividing Range, which appears to act as a low‐permeability barrier to the movement of both species. Identification of an inland flyway for waterbirds in Australia provides important context for multi‐jurisdictional cooperation and strategic management. Where resources are limited, water and wetland management efforts (e.g., environmental watering) should be preferentially located within this route. Similarly, targeting threat mitigation within common movement routes may have disproportionate importance for long‐term population viability. Given the widespread distribution of similar species globally, there are likely to be other flyways worthy of scientific and conservation management attention that could be identified using our approach. [ABSTRACT FROM AUTHOR]

To effectively monitor the residues of organochlorine pesticides (OCPs) in environmental water, this study developed a low-cost, weak matrix effect, and economically convenient solid-phase microextraction method to determine 13 OCPs residues in water. This approach used a highly selective silicone rubber (SR) thin film as the solid-phase adsorbent to prepare an easy-operate extraction bottle. After the optimization of the extraction mode, extraction time, elution solvent, and elution mode, vortexing for 10 min was selected for the adsorption of target compounds by the SR film, and 5 mL of V (hexane) : V (ethyl acetate) = 1 : 1 was used to elute the target compounds from SR film. The detection of 13 OCPs was performed by gas chromatography. The results showed that the limits of detection for the 13 OCPs ranged from 0.001 to 0.132 μg/L, and the limit of quantification was 0.2 μg/L. The linearity was good with the determination coefficients (R²) higher than 0.9973. The average recoveries of 13 OCPs in water spiked at three levels of 0.2, 1, and 20 μg/L were in a range of 73%-109% with relative standard deviations of 0.5%-13% (n=5). The method was finally employed for the monitoring of the 13 OCPs in several water samples collected from Chao Lake, Nanfei River and other major rivers in Hefei City, and the highest detection mass concentration was 3.64 μg/L. Compared with the previously reported methods, the proposed method features high sensitivity, simplicity in operation, and low cost, showing promising prospects in the multi-residue determination of OCPs in environmental water. [ABSTRACT FROM AUTHOR]

Noroviruses (NoVs) are the leading cause of non-bacterial gastroenteritis with societal costs of US$60.3 billion per annum. Development of a long amplicon nanopore-based method for dual-typing the RNA-dependent RNA polymerase (RdRp) and major structural protein (VP1) regions from a single RNA fragment could improve existing norovirus typing methods. Application to wastewater-based epidemiology (WBE) and environmental testing could enable the discovery of novel types and improve outbreak tracking and source apportionment. Here, we have developed such a method with a consensus-based bioinformatics pipeline and optimised reverse transcription (RT) and PCR procedures. Inhibitor removal and LunaScript® RT gave robust amplification of the ≈ 1000 bp RdRP + VP1 amplicon for both the GI and GII PCR assays. Platinum™ Taq polymerase showed good sensitivity and reduced levels non-specific amplification (NSA) when compared to other polymerases. Optimised PCR annealing temperatures significantly reduced NSA (51.3 and 42.4% for GI and GII), increased yield (86.5% for GII) and increased taxa richness (57.7%) for GII. Analysis of three NoV positive faecal samples showed 100% nucleotide similarity with Sanger sequencing. Eight GI genotypes, 11 polymerase types (p-types) and 13 combinations were detected in wastewater along with 4 GII genotypes, 4 p-types and 8 combinations; highlighting the diversity of norovirus taxa present in wastewater in England. The most common genotypes detected in clinical samples were all detected in wastewater while we also frequently detected several GI genotypes not reported in the clinical data. Application of this method into a WBE scheme, therefore, may allow for more accurate measurement of norovirus diversity within the population. [ABSTRACT FROM AUTHOR]

Abstract Waterbird population and species diversity maintenance are important outcomes of wetland conservation management, but knowledge gaps regarding waterbird movements affect our ability to understand and predict waterbird responses to management at appropriate scales. Movement tracking using satellite telemetry is now allowing us to fill these knowledge gaps for highly mobile waterbirds at continental scales, including in remote areas for which data have been historically difficult to acquire. We used GPS satellite telemetry to track the movements of 122 individuals of three species of ibis and spoonbills (Threskiornithidae) in Australia from 2016 to 2023. We analysed movement distances, residency periods and areas, and foraging-site fidelity. From this we derived implications for water and wetland management for waterbird conservation. This is the first multi-year movement tracking data for ibis and spoonbills in Australia, with some individuals tracked continuously for more than five years including from natal site to first breeding attempt. Tracking revealed both inter- and intra-specific variability in movement strategies, including residency, nomadism, and migration, with individuals switching between these behaviours. During periods of residency, areas used and distances travelled to forage were highly variable and differed significantly between species. Sixty-five percent of identified residency areas were not associated with wetlands formally listed nationally or internationally as important. Tracking the movements of waterbirds provides context for coordinated allocation of management resources, such as provision of environmental water at appropriate places and times for maximum conservation benefit. This study highlights the geographic scales over which these birds function and shows how variable waterbird movements are. This illustrates the need to consider the full life cycle of these birds when making management decisions and evaluating management impacts. Increased knowledge of the spatio-temporal interactions of waterbirds with their resource needs over complete life cycles will continue to be essential for informing management aimed at increasing waterbird numbers and maintaining long-term diversity.

Abstract The administration of cytostatic drugs in chemotherapy is steadily increasing, triggering thus a risk to the environment. Identifying powerful ways to effectively remove these hazardous pollutants from hospital and effluent wastewater before they discharge into the aquatic environment remains a critical and challenging task. Adsorption is among the most effective ways to treat contaminated water due to the wide availability and selectivity of the adsorbents besides the simplicity and the low start-up costs of the technique. In this work, a geopolymer, elaborated from an illito-kaolinitic clay (Douiret region of Tunisia) and industrial waste (silica fume and phosphogypsum), has been tested as promising decontamination of the cytostatic drugs paclitaxel (PCX) and irinotecan (IRI) from water samples. The foamed geopolymer was characterized using X-ray diffraction, Fourier transform infrared, scanning electron microscopy and thermogravimetric analysis before and after adsorption. Adsorption batch assays were performed using different concentrations of PCX and IRI, contact times and environmental conditions. The geopolymer had an excellent removal efficiency (almost 100% for PCX and 89% for IRI) using 20 mg of adsorbent and 2.5 mg/L of each drug concentration. The characterization results showed that cytostatic drugs were adsorbed to the geopolymer through physical interactions, pore filling, electrostatic attraction and hydrogen bonding. The specific surface area and pore volume of the geopolymer were 82.23 m2/g and 0.19 cm3/g, respectively. In addition to its cost-effective properties, the geopolymer demonstrated excellent efficiency in contaminated natural samples (including influent, effluent wastewater and surface water) denoting a great application for water purification.

Abstract This study introduces a novel ion-imprinted polymer for the ultrasensitive detection of mercury(II) in water. The ion-imprinted polymer was synthesized via a simple bulk polymerization process using methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, morpholine-4-carbodithioic acid phenyl ester as the chelating agent, and ammonium persulfate as the initiator. The electrochemical mercury(II) sensing capability of the ion-imprinted polymer was studied via the modification of a cost-effective carbon paste electrode. A stripping voltammetric technique was utilized to quantify the analyte ions following open-circuit enrichment. Critical experimental parameters, including the nature and concentration of the eluent, solution pH, preconcentration duration, ion-imprinted polymer dosage, sample solution volume and reduction potential, were systematically studied and optimized. Under optimal conditions, the sensor exhibited a linear response in the range of 1.0 to 240.0 nM, with a low detection limit of 0.2 nM. The sensor demonstrated remarkable selectivity against potential interfering ions, including lead(II), cadmium(II), copper(II), zinc(II), manganese(II), iron(II), magnesium(II), calcium(II), sodium(I) and cobalt(II). The practical applicability of the developed method was successfully validated through the analysis of real water samples, suggesting its potential for environmental monitoring applications.

Waterbird population and species diversity maintenance are important outcomes of wetland conservation management, but knowledge gaps regarding waterbird movements affect our ability to understand and predict waterbird responses to management at appropriate scales. Movement tracking using satellite telemetry is now allowing us to fill these knowledge gaps for highly mobile waterbirds at continental scales, including in remote areas for which data have been historically difficult to acquire. We used GPS satellite telemetry to track the movements of 122 individuals of three species of ibis and spoonbills (Threskiornithidae) in Australia from 2016 to 2023. We analysed movement distances, residency periods and areas, and foraging-site fidelity. From this we derived implications for water and wetland management for waterbird conservation. This is the first multi-year movement tracking data for ibis and spoonbills in Australia, with some individuals tracked continuously for more than five years including from natal site to first breeding attempt. Tracking revealed both inter- and intra-specific variability in movement strategies, including residency, nomadism, and migration, with individuals switching between these behaviours. During periods of residency, areas used and distances travelled to forage were highly variable and differed significantly between species. Sixty-five percent of identified residency areas were not associated with wetlands formally listed nationally or internationally as important. Tracking the movements of waterbirds provides context for coordinated allocation of management resources, such as provision of environmental water at appropriate places and times for maximum conservation benefit. This study highlights the geographic scales over which these birds function and shows how variable waterbird movements are. This illustrates the need to consider the full life cycle of these birds when making management decisions and evaluating management impacts. Increased knowledge of the spatio-temporal interactions of waterbirds with their resource needs over complete life cycles will continue to be essential for informing management aimed at increasing waterbird numbers and maintaining long-term diversity. [ABSTRACT FROM AUTHOR]

In this study, we designed a molecularly imprinted polymers-dispersive solid-phase extraction-high-performance liquid chromatography (MIPs-DSPE-HPLC) method, as a simple and efficient platform for the sensitive detection of two sulfonamide antibiotics (SAs) of sulfamethoxine (SMM) and sulfamethoxazole (SMZ) in environmental water samples. Using SMM and SMZ as templates, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the crosslinking agent, and azodiisobutyronitrile as the catalyst, the dual-template molecularly imprinted polymers (dt-MIPs) were successfully synthesized via surface imprinting technology and multi-template imprinting strategy. The adsorption properties of the prepared MIPs were characterized, and the adsorption capacities of MIPs towards SMZ and SMM were 27.35 mg/g and 30.92 mg/g, respectively. The detection limits of the method in three environmental water samples were in the range of 0.23–1.74 μg/L, and the recoveries were between 82.7 and 110.3%, with relative standard deviations less than 5.93%. The construction process of this MIPs-DSPE-HPLC method is straightforward, exhibits high sensitivity and selectivity, and thus provides a versatile method for the quantification of SAs in complex matrices. [ABSTRACT FROM AUTHOR]

The administration of cytostatic drugs in chemotherapy is steadily increasing, triggering thus a risk to the environment. Identifying powerful ways to effectively remove these hazardous pollutants from hospital and effluent wastewater before they discharge into the aquatic environment remains a critical and challenging task. Adsorption is among the most effective ways to treat contaminated water due to the wide availability and selectivity of the adsorbents besides the simplicity and the low start-up costs of the technique. In this work, a geopolymer, elaborated from an illito-kaolinitic clay (Douiret region of Tunisia) and industrial waste (silica fume and phosphogypsum), has been tested as promising decontamination of the cytostatic drugs paclitaxel (PCX) and irinotecan (IRI) from water samples. The foamed geopolymer was characterized using X-ray diffraction, Fourier transform infrared, scanning electron microscopy and thermogravimetric analysis before and after adsorption. Adsorption batch assays were performed using different concentrations of PCX and IRI, contact times and environmental conditions. The geopolymer had an excellent removal efficiency (almost 100% for PCX and 89% for IRI) using 20 mg of adsorbent and 2.5 mg/L of each drug concentration. The characterization results showed that cytostatic drugs were adsorbed to the geopolymer through physical interactions, pore filling, electrostatic attraction and hydrogen bonding. The specific surface area and pore volume of the geopolymer were 82.23 m2/g and 0.19 cm3/g, respectively. In addition to its cost-effective properties, the geopolymer demonstrated excellent efficiency in contaminated natural samples (including influent, effluent wastewater and surface water) denoting a great application for water purification. [ABSTRACT FROM AUTHOR]

Context: Nomadic waterbirds are highly mobile across a range of spatial and temporal scales, which makes it difficult to monitor, quantify, and predict their habitat use with traditional methods, especially between breeding events when individuals and flocks can move over vast areas. Objectives: This study aimed to provide accurate information on habitat use to improve strategic conservation management of these species, particularly the provisioning of environmental water. Methods: To overcome the challenges of distance and remoteness, we analysed a 7-year GPS satellite telemetry dataset from 141 individuals. We quantified habitat selection post-dispersal from breeding sites, and predicted habitat preference for two wading waterbird species of the Threskiornithidae family that frequently nest together at the same sites: straw-necked ibis (Threskiornis spinicollis) and royal spoonbill (Platalea regia). Results: Both long-term and short-term landscape-scale habitat associations differed between species. Royal spoonbills used fewer and more restricted habitat types than straw-necked ibis. Spoonbills displayed strong preferences for reservoirs, marshes and permanent wetlands, while ibis used both aquatic and terrestrial habitat, including areas of intensive animal production, modified pasture, and woodlands. Analysis of nocturnal versus diurnal space use showed that roosting and foraging habitat requirements for both species are distinct. Conclusions: Analysing over 1 million telemetry points revealed species-level variability in habitat use, informing resource allocation for environmental water management. Royal spoonbills are more vulnerable to habitat change due to water regime alterations, highlighting the need for focused conservation management. Differences in day and night habitat use indicate the necessity of considering roosting habitats alongside foraging habitats for effective conservation. This comprehensive understanding of waterbirds' spatiotemporal interactions with their environment is crucial for long-term management aimed at increasing waterbird numbers and maintaining diversity. [ABSTRACT FROM AUTHOR]

Due to the increased prevalence of diabetes, the consumption of anti-diabetic drugs for its treatment has likewise increased. Metformin is an anti-diabetic drug that is commonly prescribed for patients with type 2 diabetes and has been frequently detected in surface water and wastewaters, thus representing an emerging contaminant. Metformin can be prescribed in combination with other classes of anti-diabetic drugs; however, these drugs are not sufficiently investigated in environmental samples. Fabric phase sorptive extraction (FPSE) has emerged as a simple and green method for the extraction of analytes in environmental samples. In this study, FPSE coupled with a high-performance liquid chromatography diode array detector (HPLC-DAD) was employed for the simultaneous analysis of different classes of anti-diabetic drugs (metformin, dapagliflozin, liraglutide, pioglitazone, gliclazide, glimepiride, glargine, repaglinide, sitagliptin, and vildagliptin) in environmental water samples. Four different fabric membranes were synthesized but the microfiber glass filter coated with sol-gel polyethylene glycol (PEG 300) was observed to be the best FPSE membrane. The parameters affecting the FPSE process were optimized using a combination of one-factor-at-a-time processes and the design of experiments. The FPSE was evaluated as a green extraction method, based on green sample preparation criteria. The FPSE-HPLC-DAD method achieved acceptable validation results and was applied for the simultaneous analysis of anti-diabetic drugs in surface and wastewater samples. Glimepiride was detected below the quantification limit in both lake and river water samples. Dapagliflozin, liraglutide, and glimepiride were detected at 69.0 ± 1.0 μg·L−1, 71.9 ± 0.4 μg·L−1, and 93.9 ± 1.3 μg·L−1, respectively, in the city wastewater influent. Dapagliflozin and glimepiride were still detected below the quantification limit in city wastewater effluent. For the hospital wastewater influent, metformin and glimepiride were detected at 1158 ± 21 μg·L−1 and 28 ± 0.8 μg·L−1, respectively, while only metformin (392.6 ± 7.7 μg·L−1) was detected in hospital wastewater effluent. [ABSTRACT FROM AUTHOR]

High-density dispersive liquid-liquid microextraction method coupled with high-performance liquid chromatography with a diode array detector (HD-DLLME-HPLC-DAD) was developed for extraction and determination of six commonly used sulfonylurea herbicides in matrices of environmental waters. For simultaneous extraction of the target herbicides, the optimum experimental parameters that 024influence extraction efficiency were investigated. Under optimized conditions, the limit of detection (LOD) and quantification (LOQ) were 0.81.5 and 1.9=5.1 ng mL-1, respectively. The precisions in terms of relative standard deviations (% RSDs) of both intraday and inter-day precisions (n = 6) were found to be 2.92 to 7.08 and 3.01 to 8.13, respectively. Furthermore, applicability of the developed method was investigated by analyzing spiked tap, lake, river and underground water samples and satisfactory recoveries were obtained in the range of 84.3-101.7% with RSDs < 9.8% (n = 6) and the target analytes were not detected in real samples. The proposed method offered several attractive features including fast analysis time, simplicity, sensitivity, and selectivity. Therefore, the trace level enrichment and assessment of sulfonylurea herbicides residues from environmental water matrices using HD-DLLME-HPLC-DAD could be utilized as a reliable alternative in routine laboratory analysis of contaminated environmental waters. [ABSTRACT FROM AUTHOR]

In areas where science is quite incomplete, such as in the deployment and use of new environmental water reserves, it might be reasonable to expect that managers will be learning 'on the job' or 'learning by doing' as they seek to apply best available science to decision making. Similarly, it might be expected that the public would have some empathy for the challenges facing environmental managers with incomplete data on which to base decisions. However, there is also a contrasting body of literature that shows the preferences of the public and voters for certainty in outcomes. This article reviews the status of adaptive management in the context of using water to bolster environmental outcomes. We also report the results of a discrete choice experiment where respondents were asked to assign a value to adaptive management undertaken by water managers. The article reports the difficulties of developing an attribute along these lines and the challenges of encouraging the public to engage with the concept and place a value on it. This provides a platform for considering what this means more generally for environmental interventions and the acceptance of environmental policies where ecological outcomes are frequently uncertain. [ABSTRACT FROM AUTHOR]

The copper–cadmium reduction method has been applied to determine nitrogen compounds in heavily contaminated environmental water. However, there is an international demand to reduce the use of cadmium because it is harmful to humans and environment. Hence, a copper–zinc reduction continuous flow analysis system without using cadmium was developed for nitrogen-compound determination. However, the effects of seawater contaminants on this analytical method remains unknown. Therefore, in this study, the effects of contaminants on the developed method are investigated, and the applicability of the method to environmental water analysis is examined. Resultantly, interference due to magnesium precipitation is confirmed; however, this could be prevented by adjusting the concentration of the analytical reagent, i.e.,. ethylenediaminetetraacetic acid disodium. The measurement of certified reference materials under the new conditions, with precipitation countermeasures, show good results, with an accuracy of over 96 %. Additionally, a recovery study using actual environmental water afforded good results, with recovery of >95 % for all samples. These results indicate that the proposed method is an excellent, cadmium-free analytical method capable of analyzing environmental water as effectively as conventional methods.

Noroviruses (NoVs) are the most significant viral pathogens associated with waterborne and foodborne outbreaks of nonbacterial acute gastroenteritis in humans worldwide. This study aimed to investigate the prevalence and diversity of NoVs contaminated in the environmental water in Chiang Mai, Thailand. A total of 600 environmental water samples were collected from ten sampling sites in Chiang Mai from July 2020 to December 2022. The presence of NoV genogroups I (GI), GII, and GIV were examined using real-time RT-PCR assay. The genotype of the virus was determined by nucleotide sequencing and phylogenetic analysis. The results showed that NoV GI and GII were detected at 8.5% (51/600) and 11.7% (70/600) of the samples tested, respectively. However, NoV GIV was not detected in this study. NoV circulated throughout the year, with a higher detection rate during the winter season. Six NoV GI genotypes (GI.1-GI.6) and eight NoV GII genotypes (GII.2, GII.3, GII.7, GII.8, GII.10, GII.13, GII.17, and GII.21) were identified. Among 121 NoV strains detected, GII.17 was the most predominant genotype (24.8%, 30 strains), followed by GII.2 (21.5%, 26 strains), GI.3 (17.4%, 21 strains), and GI.4 (16.5%, 20 strains). Notably, NoV GII.3, GII.7, GII.8, and GII.10 were detected for the first time in water samples in this area. This study provides insight into the occurrence and seasonal pattern of NoV along with novel findings of NoV strains in environmental water in Thailand during the COVID-19 outbreak. Our findings emphasize the importance of further surveillance studies to monitor viral contamination in environmental water. [ABSTRACT FROM AUTHOR]

Context: Published evidence suggests recruitment of floodplain trees is declining in the northern Murray–Darling Basin (MDB) and that this is linked to river flow. Aims: We investigated the reproductive phenology of Eucalyptus camaldulensis and Eucalyptus coolabah to better understand tree reproductive cycles and the influence of rainfall and flow on seed production. Methods: We surveyed phenological events (bud, flower and fruit production) over 6 years, at nine sites along the Condamine–Balonne River and examined correlations between these events and meteorological parameters. Key results: For both species, event timing was consistent across sites and years and event relative abundance scores were different between years. Bud abundance was correlated with rainfall, flooding and warming temperatures and E. coolabah produced additional bud crops after floods. Conclusions: The timing of events did not differ significantly from published results for the southern MDB. Rainfall, river flows and flooding in spring resulted in more abundant bud crops in E. camaldulensis and E. coolabah , and subsequently more abundant fruit crops. Fruit dehiscence coincided with summer–autumn flooding, which provides seed for germination. Genetic and physiological factors may also influence the observed pattern. Implications: These results will inform water planning in Queensland, Commonwealth Environmental Water Holder watering actions and long-term watering plans in the northern MDB. Eucalyptus camaldulensis and Eucalyptus coolabah are floodplain trees found in the Murray–Darling Basin (MDB). This long-term study observed the timing and abundance of buds, flowers and fruits at sites in the northern MDB and looked for patterns that would indicate the influence of river flows. Bud abundance, canopy seed storage and seed fall were influenced by moisture availability in both species. Image credit: J. L. Kerr. This article belongs to the collection Environmental flows in northern Murray–Darling Basin: what we know about the science and management after a decade of practice. [ABSTRACT FROM AUTHOR]

An analytical method that combined large-volume solid-phase (Cleanert-PEP) extraction with ultra-performance liquid chromatography-tandem mass spectrometry (SPE-UPLC-MS/MS) was established for the detection of atrazine, atrazine metabolites, and topramezon residues in environmental water. The results showed that atrazine, its metabolites, and topramezon had a good linear relationship within the linear range of 0.5–50 μg/L, and the linear correlation coefficients of all compounds were r2 ≥ 0.9989. At three spiked levels of 10, 100, and 1000 ng/L, the relative recoveries rate was between 77.1% and 114.1%, with relative standard deviations (RSDs) between 0.9% and 6.8%. The limits of detection (LODs) and limits of quantification (LOQs) of all target compounds were between 0.4 and 3.0 ng/L, and between 1.2 and 10.0 ng/L, respectively. After optimisation, Cleanert-PEP was selected for pretreatment of environmental water, and its elution curve was studied, and the optimal elution volume was 6 mL. The analysis method was applied to surface water bodies around Tai'an City in Shandong Province, China, and none of the target metabolites were detected. This method has the advantages of high sensitivity, good stability, simple operation, and high efficiency. It can be used to quantify topramezon, atrazine, and atrazine metabolite residual in water samples and to investigate their behaviour in environmental water. [ABSTRACT FROM AUTHOR]

ABSTRACT Organisms that are associated with feces (“fecal indicator organisms”) are monitored to assess the potential for fecal contamination of surface water bodies in the United States. However, the effect of the complex mixtures of chemicals and the natural microbial community within surface water (“particles”) on fecal indicator organism persistence is not well characterized. We aimed to better understand how particles, including biological (e.g., potential grazers) and inert (e.g., minerals) types, affect the fecal indicator organisms Escherichia coli K-12 (“E. coli”) and bacteriophage MS2 in surface waters. A gradient of particles captured by a 0.2-µm-pore-size filter (“large particles”) was generated, and the additional particles and dissolved constituents that passed through the filter were deemed “small particles.” We measured the ratio of MS2 and E. coli that survived over a 24-h incubation period for each condition (0%–1,000% large-particle concentration in raw water) and completed a linear regression that included large- and small-particle coefficients. Particles were characterized by quantifying plankton, total bacterial cells, and total solids. E. coli and MS2 persistence was not significantly affected by large particles, but small particles had an effect in most waters. Small particles in higher-salinity waters had the largest, negative effect on E. coli and MS2 survival ratios: Significant small-particle coefficients ranged from −1.7 to −5.5 day−1 in the marine waters and −0.89 to −3.2 day−1 in the fresh and estuarine waters. This work will inform remediation efforts for impaired surface water bodies.IMPORTANCEMany surface water bodies in the United States have organisms associated with fecal contamination that exceed regulatory standards and prevent safe recreation. The process to remediate impaired water bodies is complicated because these fecal indicator organisms are affected by the local environmental conditions. For example, the effect of particles in surface water on fecal indicator concentrations are difficult to quantify in a way that is comparable between studies and water bodies. We applied a method that overcomes this limitation to assess the effects of large particles, including natural plankton that could consume the seeded fecal indicator organisms. Even in environmental water samples with diverse communities of plankton present, no effect of large particles on fecal indicator concentrations was observed. These findings have implications for the interpretation and design of future studies, including that particle characterization of surface water may be necessary to assess the fate of fecal indicators.

Mixed-mode high-performance liquid chromatography (HPLC) is increasingly used for the analysis of ionic and highly hydrophilic drugs, which are difficult to separate by conventional single-mode HPLC. In the former case, chromatographic separation is achieved using one of the several commercially available mixed-mode stationary phases, typically combinations of reversed and ion-exchange phases. Moreover, mixed-mode stationary phases can be used as solid-phase extraction (SPE) sorbents. This review focuses on the recent applications of mixed-mode stationary phases in the chromatographic analysis of bioactive compounds, such as drugs, herbicides, and pesticides. Specifically, we briefly summarize HPLC methods utilizing mixed-mode stationary phases and SPE pretreatment procedures utilizing mixed-mode sorbents developed in the last decade, thus providing a reference work for overcoming the difficulties in analyzing ionized or hydrophilic drugs by conventional reversed-phase chromatography. [ABSTRACT FROM AUTHOR]

Triazole fungicides are widely used in agricultural production, and the residues could transmit into water bodies through environmental media, posing a threat to the ecosystem and human health. In this study, aluminum chloride hexahydrate and tetra (4- carboxyphenyl) porphyrin (TCPP) were used as functional monomers to prepare three-dimensional Al-TCPP metal organic framework (MOF) nanosheets, and Al-TCPP nanosheets were used as adsorbents to construct an efficient adsorption and removal method for 16 triazole fungicides in water. The effects of Al-TCPP nanosheets dosage, adsorption time and pH value on the adsorption performance of triazole fungicides were investigated, and the best adsorption removal conditions were obtained. Three typical fungicides were selected to study the adsorption kinetics, adsorption isotherm and adsorption thermodynamics of AlTCPP nanosheets. The results showed that the adsorption of triazole fungicides by Al-TCPP nanosheets was a monolayer chemical adsorption, which conformed to the quasi-second-order kinetic model. The adsorption process was spontaneous exothermic reaction, and low temperature was beneficial to the reaction. The established method was used to adsorb triazole fungicides in different environmental water samples, and the results showed that the removal rates of Al-TCPP nanosheets for 16 triazole fungicides in different environmental water samples were all higher than 85%. In summary, Al-TCPP nanosheets have good practicability for the adsorption and removal of triazole fungicides, which can provide new idea and novel methods for the study of residue removal of triazole fungicides in environmental water [ABSTRACT FROM AUTHOR]

Escherichia albertii is an emerging enteropathogen and its distribution in various foods and environmental samples has been reported in many regions around the world. In this study, we aimed to identify effective isolation and detection methods for E. albertii in various foods and environmental water samples. E. albertii-specific polymerase chain reaction (PCR) was positive in chicken, oyster, river water, and wastewater samples, and E. albertii was isolated from these PCR-positive samples except the wastewater sample. E. albertii was not isolated from any of the samples without screening PCR; therefore, PCR is useful for the detection and isolation of E. albertii in foods and environmental water samples. The effect of two-step enrichment with four kinds of selective enrichment broth was compared with cycle threshold (Ct) values of the E. albertii-specific real-time PCR assay and the isolation results. The Ct values in three out of five samples were lower in the second enriched culture than those of the first enriched culture, and E. albertii was isolated from enriched cultures showed Ct values <25. These results suggest that the population of E. albertii in these three samples increased in the second enriched culture compared with the first enriched culture, and isolating E. albertii from an enriched culture showing Ct values <25 is an efficient method. Genetic analysis was performed to E. albertii isolates from food, environmental water, and human fecal samples, and all the isolates possessed eae, and isolates from chicken, pork, and river water samples showed the same EAOg type as E. albertii isolated from human fecal samples. Therefore, it was suggested that a continuous attention should be paid to E. albertii in food and environment. [ABSTRACT FROM AUTHOR]

Escherichia albertii is an emerging foodborne pathogen that causes diarrhea. E. albertii has been isolated from various foods, including pork and chicken meat, and environmental waters, such as river water. Although many food poisoning cases have been reported, there have been insufficient analyses of bacterial population behaviors in food and environmental water. In this study, we inoculated 2–5 log CFU of E. albertii into 25 g of pork, chicken meat, Japanese rock oyster, Pacific oyster, and 300 mL of well water and seawater at 4°C, 10°C, 20°C, and 30°C, and analyzed the bacterial population behavior in food and environmental water. After 3 days at 4°C, the population of E. albertii strain EA21 and EA24 in foods maintained approximately 4 log CFU/25 g. After 3 days at 10°C, the population of E. albertii strains in pork and oysters maintained approximately 4 log CFU/25 g, and that in chicken meat increased to approximately 5–6 log CFU/25 g. After 2 days at 20°C, E. albertii strains grew to approximately 6–7 log CFU/25 g in pork and chicken meat, and E. albertii strain EA21 but not EA24 grew to 4.5 log CFU/25 g in Japanese rock oyster, E. albertii strain EA21 but not EA24 slightly grew to 3.1 log CFU/25 g in Pacific oyster. After 1 day at 30°C, E. albertii strains grew to approximately 7–8 log CFU/25 g in chicken meat and pork, grew to approximately 4–6 log CFU/25 g in Japanese rock oyster, and 6–7 log CFU/25 g in Pacific oyster. These results suggest that E. albertii survives without growth below 4°C and grew rapidly at 20°C and 30°C in foods, especially in meat. E. albertii strains did not grow in well water and seawater at 4°C, 10°C, 20°C, and 30°C. The population of E. albertii strains in well water and seawater decreased faster at 30°C than at 4°C, 10°C, and 20°C, suggesting that E. albertii has low viability at 30°C in environmental water.

A novel composite material based on acrylonitrile‐butadiene‐styrene (ABS) and carbon black (CB) was proposed here. Different ratios between CB and ABS (40 : 60–60 : 40 %, w/w) were studied to obtain a substrate with improved electrochemical properties. These materials were characterized by techniques such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Raman and Fourier transform infrared (FT‐IR) spectroscopies and scanning electron microscopy (SEM). Under the CB/ABS substrate (50 : 50 %, w/w), a lower charge transfer resistance (854 Ω) and a higher heterogeneous electron transfer constant (K0=1.551×10−3 cm s−1) were found, indicating a kinetically more favorable reaction. To improve the electroanalytical performance of the CB/ABS electrode (50 : 50 %, w/w), silver nanoparticles (AgNPs) were electrodeposited using recycled silver from photographic waste, whose presence was confirmed by SEM imaging and Raman spectra. A method using square wave anodic stripping voltammetry (SWASV) and Pb2+ as model species was developed, where a wider linear working range (4.0 to 40.0 μg L−1) and lower detection limit (0.4 μg L−1) were achieved for the modified electrode. The electrode modification process was highly reproducible (RSD=9.7 %, n=9, inter‐electrode), with precise electrochemical responses (RSD=3.6 %, n=9, intra‐electrode). The applicability was demonstrated in two seawater samples, where recovery levels between 94 and 106 %, as well as statistically similar results to those obtained by atomic absorption spectroscopy, attested to the reliability of the analysis. Furthermore, it is noteworthy that an appropriate selectivity was achieved even in the presence of other metallic species. The proposed composite material is low‐cost, robust, versatile, and can be a promising tool for additive manufacturing of electrochemical sensors. [ABSTRACT FROM AUTHOR]

This study presents a novel approach for the quantification of silver ions in environmental water through the utilization of liquid-liquid microextraction, employing natural deep eutectic solvents in conjunction with inductively coupled plasma emission spectroscopy. The extracted solvent was characterized by Fourier transform infrared spectroscopy (FT-IR). The impact of various extractant types, extractant molar ratio, extractant volume, extraction time, and salt concentration on the efficacy of silver ion extraction was investigated. The findings indicate that the optimal extraction efficiency was attained by utilizing a 5-mL aqueous solution volume, containing 1000 μL thymol/lactic acid NADES 1:3, a salt concentration of 1 mg mL−1, a pH value of 4, and a vortex time of 4 min. Upon implementing the optimized experimental conditions, the recovery of target metal ions was from 96.9 to 101.0%. The relative standard deviations were observed to be within the range of 1.5 to 2.7%. The present study demonstrates the reproducibility, accuracy, and reliability of the method for detecting silver ions in environmental water, with linear range of 5~1000 ng mL−1 and limits of detection (LOD) and limits of quantification (LOQ) of 1.52 ng mL−1 and 5.02 ng mL−1, respectively. [ABSTRACT FROM AUTHOR]