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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]

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]

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]

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]

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]

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]

This study involved the development of an in-pipette tip solid-phase microextraction (SPME) method using activated charcoal as an adsorbent. Simultaneous determination of three sulphonamide antibiotic residues in environmental water was performed using this method, coupled with high-performance liquid chromatography-photodiode array (HPLC-PDA) detection. Seven extraction parameters were optimised by one-variable-at-a-time (OVAT) and response surface (RSM) methods. Optimum extraction efficiency was achieved when 10 mL of sample solution at a natural pH (pH 5–6) was loaded through a 1 mL pipette tip packed with 10 mg of adsorbent, washed with 1 mL of hexane and eluted with 500 µL of 1% ammonium in methanol solution. Under the optimised experimental condition, this method manifested good linearity (5–500 µg L−1) at the coefficient of determination, R2 of 0.9992 to 0.9993, high sensitivity (limit of detection, LOD: 0.38–1.14 µg L−1; limit of quantification, LOQ: 1.14–3.35 µg L−1), and satisfactory recoveries (82.8–108.7%) with acceptable reproducibility (RSD < 4.6%). Real sample analysis of five environmental water samples sourced from Universiti Malaya, Kuala Lumpur and Malacca showed that the samples contained either none or traces of the target sulphonamides (SAs) with their concentration lower than the LOQs. In contrast to other methods, the comparison outcomes depicted that this in-tip SPME method was beneficial in terms of its simple, reusable, cost-saving setup together with a significant reduction in chemical consumption. [ABSTRACT FROM AUTHOR]

The rivers of the south-eastern Murray-Darling Basin (MDB) and the associated irrigation areas of the southern riverine plain (SRP) in south-eastern Australia have undergone major hydrological changes over the last 30 years. These include a period of lower rainfall; a rebalance of surface water diversions between consumptive and environmental water uses under the MDB Basin Plan, improvements in water infrastructure; water trade out of the region; and falling groundwater levels. All these changes increase losses from streams to groundwater systems; potentially leading to the need for greater releases from dams to maintain baseflow in the major rivers. Baseflow is important for conveyance of water, water quality and baseflow-dependent ecosystems during dry periods. Hydrological changes in the SRP will reduce the streamflow by 2029–30 by an estimated 80 to 320 GL/yr. Further hydrological changes by 2029–30 will reduce the streamflow by another 50 GL/yr in the following decade. This is the first assessment of the cumulative stream impacts of the SRP and is relatively lower than previous assessments for single drivers. The current approach of mitigating unexpected losses is to increase conveyance loss budgets as required. This could be extended to mitigate the lower end of potential impacts; but further steps to reduce losses may be required towards the upper end. Further actions include a review of extraction limits for surface water and groundwater, trigger levels, and a greater shift towards conjunctive water management. Groundwater extraction, which has dominated impacts, is increasing from a relatively low proportion of the extraction limit in Goulburn-Murray Sedimentary Plain and shallow aquifers of the SRP. Over time, climate change will become more dominant as a driver. Most monitoring required to support mitigation already exists, but data is not collated or reported in a form relevant for stream impacts. Modelling also needs to be updated with reporting of more relevant outputs. [ABSTRACT FROM AUTHOR]

Accelerating the design and implementation of environmental flows (e-flows) is essential to curb the rapid, ongoing loss of freshwater biodiversity and the benefits it provides to people. However, the effectiveness of e-flow programs may be limited by a singular focus on ensuring adequate flow conditions at local sites, which overlooks the role of other ecological processes. Recent advances in metasystem ecology have shown that biodiversity patterns and ecosystem functions across river networks result from the interplay of local (environmental filtering and biotic interactions) and regional (dispersal) ecological processes. No guidelines currently exist to account for these processes in designing e-flows. We address this gap by providing a step-by-step operational framework that outlines how e-flows can be designed to conserve or restore metasystem dynamics. Our recommendations are relevant to diverse regulatory contexts and can improve e-flow outcomes even in basins with limited in situ data. [ABSTRACT FROM AUTHOR]

Building on a previously developed workflow for rapid and sensitive pathogen detection by qPCR, this work has established a sample treatment strategy that produces consistent quantification efficiencies (QEs) for Campylobacter jejuni against a complex and highly variable sample matrix from a suburban river. The individual treatments most effective at minimizing the inhibitory effects of the sample matrix were pH buffering with HEPES (50 mM, pH 5.7) and addition of the surfactant Tween 20 (2% v/v). Unexpectedly, sample acidification (pH 4–5) resulting from the use of aged Tween 20 that had undergone partial hydrolysis, appeared to play a key role in enhancing QE. This effect could be replicated by direct pH adjustment with dilute hydrochloric acid and may be linked to the solubilization and removal of inhibitory particles at an acidic pH. While the effectiveness of each individual treatment method varied, a combined treatment of either HEPES buffer + Tween 20, or direct pH adjustment + Tween 20, consistently produced QEs of 60%–70% and up to 100%, respectively, over a sampling period of one year. The consistency and scalability of this workflow make it a suitable alternative to culture-based ISO methods for detecting Campylobacter spp. [ABSTRACT FROM AUTHOR]

The large-scale use of sulfonamide antimicrobials in human and veterinary medicine has seriously endangered the ecological environment and human health. The objective of this study was to develop and validate a simple and robust method for the simultaneous determination of seventeen sulfonamides in water using ultra-high performance liquid chromatography–tandem mass spectrometry coupled with fully automated solid-phase extraction. Seventeen isotope-labeled internal standards for sulfonamides were used to correct matrix effects. Several parameters affecting extraction efficiency were systematically optimized, and the enrichment factors were up to 982−1033 and only requiring about 60 min per six samples. Under the optimized conditions, this method manifested good linearity (0.05–100 μg/L), high sensitivity (detection limits: 0.01–0.05 ng/L), and satisfactory recoveries (79–118%) with acceptable relative standard deviations (0.3–14.5%, n = 5). The developed method can be successfully utilized for the determination of 17 sulfonamides in pure water, tap water, river water, and seawater. In total, six and seven sulfonamides were detected in river water and seawater, respectively, with a total concentration of 8.157–29.676 ng/L and 1.683–36.955 ng/L, respectively, and sulfamethoxazole was the predominant congener. [ABSTRACT FROM AUTHOR]

Summary: Allocation of water specifically to the environment (often dubbed 'environmental water' or 'environmental flows') can be contentious within government, among irrigators and between community members. The reduction in supply of fresh water has led to questions surrounding the efficiencies and ecological value of securing these adequate flows for waterways. This literature review examines the evidence on these perceptions of environmental water allocations, focusing foremost on general public, irrigator, Indigenous and decision-maker perspectives. Existing studies are predominantly in Global North areas such as Australia, Canada and the USA. Two themes featured strongly in the papers: the importance of personal values in the acceptance of environmental water and the perception of fairness in environmental water allocation processes. Although the research area has been expanding, there is still limited representation in types of study, disciplinary backgrounds and study locations, and as such many research opportunities remain. [ABSTRACT FROM AUTHOR]

A microextraction method has been developed for the determination of rhodamine B (Rh-B) in water and cosmetics by separation and preconcentration with liquid microextraction based upon a switchable hydrophilic solvent and determination by spectrophotometry. The analyte was extracted into the triethylamine (TEA) phase using sodium hydroxide (NaOH) to convert protonated triethylamine carbonate (P-TEA-C) to triethylamine. Various analytical parameters such as the pH of the sample solution, extraction solvent volume, and sample volumes affecting the quantitative recovery values of rhodamine B were optimized. The limit of detection (LOD) and limit of quantification (LOQ) were 2.96 and 9.88 ng/mL, respectively. The developed method was successfully applied to the determination of rhodamine B and satisfactory recovery values were obtained. The developed approach is fairly fast and an environmentally friendly alternative for the separation and preconcentration of rhodamine B water and cosmetic samples. [ABSTRACT FROM AUTHOR]

The Murray–Darling Basin Plan, a major initiative to return water from irrigators to the environment, has been lauded as world-class water reform. The enabling legislation for the Basin Plan, the Water Act, gains its constitutional legitimacy from international treaties such as the Ramsar Convention on Wetlands. This Act mandated that water be returned from consumptive uses to the environment. An allocation of 2,750 GL/yr was set but has been reduced by the 'Sustainable Diversion Limit Adjustment Mechanism' (SDLAM), intended to achieve equivalent environmental benefits with less water. We present a synthesis of changes in decision contexts that have led to water reforms being 'watered down'. We analysed the policy discourse of water reform to assess whether SDLAM projects will achieve outcomes congruent with Australia's international treaty obligations. We found little or no alignment between the purpose of the SDLAM projects and the principles of the treaties and the Water Act. As water scarcity increases under climate change, attempting to conserve wetlands (including rivers) with less water while maintaining or increasing irrigation diversions is likely to prove maladaptive. A major reframing of environmental water policy and management is required to enable meaningful and effective adaptation to climate change. [ABSTRACT FROM AUTHOR]

Ethylene glycol dinitrate (EGDN) is a liquid nitrate ester, a secondary explosive. In the past, it was used as an explosive ingredient in dynamite along with nitroglycerine. Due to its various applications, the reliable detection of EGDN in the environment is a key issue for both forensic and environmental applications. In these areas, sensitive and reliable methods for determining the concentration of nitro compounds are needed. Microextraction by packed sorbent (MEPS) is an innovative approach to green technology in the sample preparation field. Compared to conventional solid-phase extraction (SPE), MEPS uses a smaller sample volume and can be easily combined with various chromatographic techniques. An important benefit is the reduction of sorbent amount and up to 100-times repeatable use compared to disposable SPE columns, thus reducing the costs of analysis as well as waste production. Optimal extraction parameters for isolating EGDN from water, e.g., 30 µL of toluene as extraction agent, working in one cycle and in draw/discard mode, were selected. Method validation was performed, obtaining a limit of detection and a limit of quantification of 0.45 pg/μL and 1.34 pg/μL, respectively. Accuracy in terms of recovery rates was evaluated over a wide concentration range, obtaining values from 83.7 to 90.0%. The satisfactory linearity expressed by the coefficient of determination was 0.9914. A matrix factor of −9.3% indicates a weak matrix effect. The application to real environmental water samples and a forensic post-blast wash water sample was realized. EGDN detection in the post-blast samples provides valuable information for forensic technicians. [ABSTRACT FROM AUTHOR]

• Defect-rich Co/N-doped hierarchically porous carbons (Co/N-DHPCs) are fabricated. • Co/N-DHPCs display excellent adsorption capacity for organophosphorus pesticides. • Pore-filling, hydrophobic and π-π interactions are involved in the adsorption process. • Defects and pyrrolic-N generate abundant adsorption sites. • Co/N-DHPCs have excellent reusability and salt-tolerance. Organophosphorus pesticides (OPPs) severely pollute various environmental water due to their excessive use, and it is extremely urgent to develop novel adsorbents with high adsorption capacities, rapid removal rate and easily recovery for the removal of OPPs. In this study, defect-rich Co/N-doped hierarchically porous carbons (Co/N-DHPCs) were constructed by pyrolyzing acid-etched ZIF-67 precursor. The developed Co/N-DHPCs possessed rich defects, well-developed hierarchical porous structure, high specific surface area and excellent magnetic property, and exhibited large adsorption capacities of 103.81∼126.10 mg g-1 and high removal efficiencies of 94.06 %∼100.00 % for fenitrothion, fenthion and phosalone within 15 min. The exceptional adsorption performance of Co/N-DHPCs could be attributed to the pore-filling effect, hydrophobic and π-π interactions, as well as the new active sites formed by rich defects and N heteroatoms doping. In addition, the magnetic property of Co/N-DHPCs enabled rapid and straightforward separation from aqueous solution. The Co/N-DHPCs also showed good reusability with removal efficiencies of 85.24 % after five consecutive recycles. Furthermore, the developed Co/N-DHPCs demonstrated remarkable removal efficiencies of OPPs in seven environmental water samples, particularly in high-salt seawater. This work provides a kind of reliable adsorbents for removing pollutants in environmental water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mannitol-modified magnetic nanoparticles (MMNPs) enhanced adsorption of polar E120 dye. • Extensive characterization of MMNPs, N-doped carbon dots (N-CDs); and Density functional theory studied E120 interactions. • E120 detection in water, juice; reliable, eco-friendly alternative to traditional methods. • Fluorometric method linear range 1–160 μg.mL−1, and low detection limits. In this study, mannitol-functionalized magnetic nanoparticles (MMNPs) as a unique nanosorbent and N-doped fluorescent carbon dots (N-CDs) as a cost-effective nanosensor were created and utilized, for the first time, for dispersive micro-solid-phase extraction (Dµ-SPE) to determine carmine (E120) dye in water samples and juices. The modification of the magnetic nanoparticles with mannitol was designed to enhance the responsive potential for adsorption of the polar E120 dye from complex sample matrices through electrostatic interaction. The as-fabricated N-CDs fluorescent probe exhibited a high fluorescence quantum yield (Φs) of 43.1 %, allowing for accurate fluorometric detection of E120 dye. The as-synthesized MMNPs nanosorbent and fluorescent N-CDs nanoprobe were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), thermogravimetric analysis (TGA), and vibrating-sample magnetometer (VSM). Density functional theory (DFT) studied the E120 dye structure using Gaussian 09 to explore the interactions between E 120 dye molecules and MMNPs/N-CDs. The impact of the critical adsorption and detection experimental factors was investigated and adjusted. A minimal amount of MMNPs nanosorbent (150 mg) is sufficient for E120 extraction in an acceptable time of 15 min. Furthermore, with a high determination coefficient, the adsorption characteristics fit with the models of Langmuir isotherm and first-order kinetics. The maximum adsorption capacity (qm) of the as-fabricated MMNPs was 87.7 mg.g−1. After adsorption, E120 dye was fluorometrically analyzed using nitrogen-doped carbon dots as a fluorescent nanosensor via the inner filter effect (IFE) mechanism. Under the optimized conditions, the proposed fluorometric procedures showed a linear increase in the fluorescence ratio with increasing the E120 concentration in the range of 1.0 – 160.0 μg.mL−1 with detection (LOD) and quantitation (LOQ) limits of 0.27 and 0.83 μg.mL−1, respectively. The relative standard deviation (%RSD) did not exceed 2.34 %. The proposed methodology was successfully applied to determine E120 dye in juice and environmental water samples with % recovery ranged from 89.2-106.1 % and 92.9–107.2 %, respectively offering a reliable and environmentally friendly alternative to traditional detection methods with potential applications across various industries. [ABSTRACT FROM AUTHOR]

Ferrous ion (Fe2+) can indicate the redox situation of water and also plays an important role in maintaining the ecological balance of water bodies. However, due to the redox-active property of Fe2+, it is still a huge challenge to sensitively and accurately determine Fe2+ especially in interstitial water. Herein, we prepared a ferrozine gel rod for valence fixation during sampling and subsequent smartphone-based detection of Fe2+. The electrode potential of the redox pair can be varied through the formation of Fe2+-ligand complexes, and when E complex was higher than E O 2 / OH − , the oxidation of Fe2+ by O 2 was hindered, thus achieving the valence fixation of Fe2+. Six ligands were screened, and it was found that ferrozine could effectively increase the redox potential after complexing with Fe2+, and also exhibits an obvious color change while fixing the valence of Fe2+. To facilitate Fe2+ detection, a cross-linked porous polymer gel rod prepared by acrylamide and sodium alginate was used to encapsulate the ferrozine molecules. The ferrozine gel rod enabled fixation the valence of Fe2+ longer than 30 days, and the resulted purple-red color was pictured and analyzed by a smartphone. Ultimately, the developed ferrozine gel rod sensing system was able to achieve sensitive and linear detection of Fe2+ in the range of 1–200 μM with the limit of detection as low as 0.33 μM, and it also exhibited excellent selectivity and anti-interference ability. The accuracy and reliability of the method was verified by the determination of Fe2+ in spiked water samples and certified standard reference water samples. Finally, the ferrozine gel rod sensing system was successfully applied to in-situ detection of Fe2+ in interstitial water, overlying water and upper water of lake and river. This facile system that enabled valence fixation and fast detection is promising for detection of Fe2+ in environmental waters. [Display omitted] • This is the first study about pre-fixing the Fe2+ valence during sampling. • The ferrozine gel rod enabled fixation the valance of Fe2+ in water longer than 30 days. • The ferrozine gel rod allowed in-situ detection of Fe2+ combining with smartphone. [ABSTRACT FROM AUTHOR]

[Display omitted] • The RPA-CRISPR/Cas12a technology was utilized to carry more signals. • The glucose oxidase-modified MB linked to single-stranded DNA were synthesized to induce color signals. • An aptasensor platform utilizing RPA-CRISPR/Cas12a technology to accurately identify MC-LR was established. • The LOD of our developed method for MC-LR was 0.1 μg/L. Microcystin-LR (MC-LR) is a significant environmental pollutant that presents a substantial risk to public health. The monitoring with simple approaches is essential for the prevention and management of MC-LR. In this study, we present an aptasensor platform utilizing recombinase polymerase amplification (RPA)-CRISPR/Cas12a technology to accurately identify MC-LR. The MC-LR aptamers were attached to magnetic beads (MBs) following combination with cDNA by hybridization, resulting in the formation of the MB aptasensor. Subsequently, glucose oxidase (GOx)-modified MB were synthesized using single-stranded DNA (MB-ssDNA-GOx) in order to induce alterations in color upon exposure to the TMB-glucose system. The colorimetric signal was visible to the naked eye and exhibited a positive correlation with MC-LR concentration. The sensing platform described in this study demonstrated great sensitivity and achieved a limit of detection of 0.1 μg/L. Furthermore, this methodology exhibited exceptional selectivity and favorable recovery rates, hence showcasing its strong suitability for the analysis of actual water samples. Hence, the assay exhibites significant potential for future environmental monitoring. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cauliflower waste-garlic as substrates for synthesis of multi-doped CQDs. • A fast green microwave-driven synthesis of multi-doped CQDs has been developed. • The synthesis process is superior to other reported synthesis methods. • The CQDs have high quantum yield (42 %), excellent stability, and water solubility. • The CQDs have been applied as an optosensor for iron in water and ampoules. A simple method for the synthesis of multi-doped carbon quantum dots (CQDs) has been developed via a fast, affordable, and green pathway from natural, nontoxic, and inexpensive substrates as garlic and cauliflower leaves and stalk as a plant by-product by the aid of microwave. The synthesized fluorescent CQDs have excellent quantum yield of 42 % at λ ex /λ em of 330/411 nm with superb stability. The CQDs were fully described using energy-dispersive X-ray, X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, Zeta potential, UV–visible spectroscopy, and fluorescence spectroscopy which demonstrate that CQDs are doped with multiple elements including sulfur, nitrogen, phosphorus, potassium, sodium, and calcium. It has been noted that Fe3+ specifically quenches the CQDs' fluorescence, unlike other heavy metals. Based on this phenomenon, the produced CQDs revealed outstanding results as a fluorescent optosensor for iron determination over the concentration range of 10.0–400.0 μM with a limit of detection of 3.29 μM. The proposed method is effective for determining Fe3+ in pharmaceutical dosage form with mean % recovery of 98.73 ± 0.75 %. Additionally, the synthesized CQDs also showed a significant promising potential in environmental applications for detection of Fe3+ in tap, irrigation, and river water with mean % recovery of 99.45 ± 1.71, 100.57 ± 1.32, and 101.49 ± 2.44 %, respectively. Several greenness measures and software approved the greenness of the designed optosensor. This approach proved that green synthesis could furnish CQDs from natural low-cost substrates with distinct outstanding characteristics that are suited for certain uses without consuming hazard materials unlike traditional methods. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new magnetic adsorbent was facilely prepared by one-pot hydrothermal strategy. • Multiple interactions contributed to the capture of female-steroid hormones. • Detailed extraction mechanism was studied. • Sample preparation greenness of developed method was assessed. • Method for the analysis of trace analytes in water and urinary samples was developed. Rapid and efficient extraction is highly desired in the accurate quantification of female-steroid hormones (FSHs) in complex samples. In this context, an active sites-rich magnetic adsorbent (MAC) modified with carboxylated multiwalled carbon nanotubes and 4-vinylphenylboronic acid was facilely synthesized through one-pot hydrothermal technique for the magnetic solid phase extraction (MSPE) of FSHs in water and urine samples. Various characterizations revealed that the prepared adsorbent contained abundant functional groups, acceptable magnetic properties, high surface area and good stability. Due to the multiple interactions, the developed MAC/MSPE exhibited high isolation and preconcentration capability towards studied FSHs within 10 min. The concentration factors were 151–354 and the adsorption capacity was as high as 3.2 mg/g. Adsorption behaviors of MAC/MSPE towards FSHs were studied based on adsorption kinetics and isotherm experiments. After optimizing the extraction parameters, the MAC/MSPE was combined with HPLC to sensitive and reliable monitoring of studied FSHs in various waters and female urine samples. The limits of detection and recoveries with different spiked contents were 0.0015–0.0026 μg/L and 80.1–119 %, respectively. Accuracy of the established method was evaluated by confirmatory testing. Moreover, sample preparation greenness of the developed method was assessed. The present study uncovered the prospect of MAC/MSPE in the rapid and highly capable capture of FSHs, and also supplied a sensitive and reliable approach for the monitoring of trace FSHs in complex samples. [ABSTRACT FROM AUTHOR]

A microextraction procedure that is rapid and simple to extract and preconcentrate ketoprofen and naproxen is proposed. An environmentally friendly supramolecular solvent was applied as an extraction solvent and proved to be efficient in the extraction of ketoprofen and naproxen from environmental water. The design of experiment approach was used to screen, optimize significant parameters, and determine optimum experimental conditions. Under optimized experimental conditions, the vortex-assisted supramolecular solvent dispersive liquid–liquid microextraction provided a good linearity (0.57–700 µg L−1), low limits of detection (0.17–0.24 µg L−1) and extraction reproducibility below 9%. The high percentage relative recoveries (93.6–101.4%) indicated that the method is not affected by matrix. The practical applicability of the method was assessed by analysing ketoprofen and naproxen in river water and effluent wastewater samples. Both analytes were found in effluent wastewater. [ABSTRACT FROM AUTHOR]

16S rRNA gene sequencing was used to analyze the changes in the microbial community structure of Macrobrachium rosenbergii (M. rosenbergii) larvae and environmental water at different stages (0, 7, 14 and 21 days). The PICRUSt was used to precalculated the predicted genes and their functions. The Alpha and Beta diversity analysis showed that the abundance and uniformity of the flora of larvae and water samples were significantly different at four stages. At the phylum level, Proteobacteria, Planctomycetes, Firmicutes and Bacteroidetes were the dominant flora of larvae, while Proteobacteria, Bacteroidetes and Actinobacteria were the dominant flora of environmental water. But at the genus level, Raoultella and Blastopirellula were the main changes in larvae, and Dyadobacter, Flavobacterium and Pseudomonas were the main changes in environmental water. The gene function prediction analysis indicated that the amino acid metabolism, immune system, immune system disease, nervous system, sensory system and other pathways enriched in the different stages of larvae and environmental water were closely related to the breeding of M. rosenbergii. This research might provide theoretical basis and guidance for the high-quality breeding of M. rosenbergii. The abundance and uniformity of the flora of larvae and environmental water were significantly different at different stages. Several flora were found that related to the growth and development of larval. KEGG pathways enriched at different stages of larvae and environmental water were closely related to the breeding of larvae. [ABSTRACT FROM AUTHOR]

A simple, direct injection and non-derivatized analytical method was developed for rapid determination of six highly polar compounds, including ethephon, glyphosate, glufosinate, aminomethylphosphonic acid, 3-methylphosphinicopropionic acid, and glufosinate-N-acetyl in environmental water by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The environmental water samples were centrifuged and filtered through 0.22 μm filter membrane to remove solids and were directly injected for quantitative analysis without derivatization. The target compounds were separated by Waters Acquity UPLC HSS T3 column (100 mm × 2.1 mm, 1.8 μm). Chromatographic separation was carried out by gradient elution with mobile phase A (water with 0.1% formic acid and 5 μmol/L medronic acid) and mobile phase B (methanol). The target compounds were finally detected using electrospray ionization and multiple reaction monitoring mode (MRM). Quantitative analysis was performed using the external standard calibration curves. The results showed that all six compounds had good linear relationship within their respective linear ranges, and the coefficient of determination (R²) were higher than 0.99. The average recoveries of six compounds in water samples were from 75% to 100% at spiked levels ranging from 10 μg/L to 200 μg/L. The intraday and inter-day relative standard deviations(n=6) were 3.6%-7.0% and 4.3%-7.5%, respectively. The limits of quantification (LOQ) were 0.5-10 μg/L. Ten surface water samples collected from three areas were detected using the established method, and the results showed that the six compounds were all not detected. Compared with other derivatization methods, this method has the advantages of simplicity, rapidity, good reproducibility, and high sensitivity, and it may provide reference for the detection of highly polar compounds such as ethephon, glyphosate, glufosinate, and their metabolites in environmental water. [ABSTRACT FROM AUTHOR]

BACKGROUND: Benzalkonium chloride has a non-oxidizing bactericidal effect and is widely used in medical and health service. With the discharge of sewage into the environment, benzalkonium chloride has been identified as a harmful compound that may seriously inspect susceptible organisms in the ecosystem. Exact quantitative analysis of benzalkonium chloride in environmental water is of great significance for human and ecological environmental health. However, low content of benzalkonium chloride exist in environmental water. The interference of a complex matrix causes false positive results to occur easily. Therefore, the detection method is required to have lower detection limits and more accurate qualitative analysis ability. OBJECTIVES: To establish a method for the determination of three benzalkonium chloride homologues (n-C12H25 -C9H13NCl, n-C14H29 -C9H13NCl, n-C16H33 -C9H13NCl) in environmental water. METHODS: Ultra-high performance liquid chromatography quadrupole/ electrostatic field orbitrap high resolution mass spectrometry (UPLC-Q-Orbitrap HRMS) was used. The sample was filtered through a 0. 22μm membrane, and then mixed with the same volume of methanol. The mobile phase consisted of 10mmol/ L ammonium acetate aqueous solution which contained 1% (V / V) triethylamine as mobile phase B and methanol as phase A, with gradient elution. Accucore C18 column (150mm×2. 1mm,2. 6μm) was used to separate the baseline of three benzalkonium chloride within 6 minutes, and the data were collected by electrostatic field orbitrap mass spectrometry in SIM mode at 60,000 resolution. RESULTS: The contents of three benzalkonium chloride within the range of 0. 10 - 10. 0μg/ L had a linear relationship (r>0. 999). The detection limits ranged from 0. 03 to 0. 06μg/ L. The recoveries of three kinds of benzalkonium chloride were 86. 7%-111. 2%. CONCLUSIONS: Verified by samples, this method meets the detection limits and has anti-interference abilities of three benzalkonium chloride homologues in surface water and shallow groundwater. Moreover, it was identified that the suspected disrupting chemical of cetyl dimethyl benzyl ammonium chloride is propylene glycol fatty acid ester at m / z 360. 323. [ABSTRACT FROM AUTHOR]

Environmental DNA (eDNA) is a highly sensitive and cost‐effective tool that is increasingly being applied to studies of biodiversity and species detection. This non‐invasive method relies on the collection of environmental samples that contain genetic material being shed into surrounding environment by the target organism/s. While forensic science has a long history of using molecular tools for collecting DNA from the environment, the detection of human DNA from environmental water samples has been limited. This study investigated the detection and degradation rates of human eDNA in water samples under controlled laboratory conditions. Using a human‐specific qPCR assay targeting the ND1 region of human mitochondrial DNA, eDNA degradation over time in water spiked with human blood was assessed. Recovery of nuclear DNA was investigated by determining if routine DNA short tandem repeat (STR) profiles of the blood source could be generated. Results demonstrated that human eDNA remains detectable for up to 11 days under laboratory conditions in environmental water and up to 35 days in distilled water. Partial STR profiles could be recovered from environmental water only up to 24 h, while, in distilled water, partial profiles continued to be recovered up to 840 h. These findings demonstrate that sampling human eDNA from aquatic samples can provide reliable human DNA detection within relatively short time windows, assisting law enforcement agencies by providing information about the potential time an individual may have been present in an area or assisting in the detection and location of a body or remains in aquatic environments. [ABSTRACT FROM AUTHOR]

Environmental water‐targeted surveillance of migratory aquatic birds at overwintering sites is potentially one of the most effective approaches for understanding the ecology of avian influenza viruses (AIVs). In this study, we improved the method for AIV isolation from environmental water samples by making a minor modification to our previously reported process. We experimentally demonstrated that the AIV recovery efficiency of the modified method was 10–100‐fold higher than that of the original method. This improved isolation method allowed us to isolate a considerably larger number of AIV isolates from environmental water samples collected at an overwintering site for tens of thousands of migratory aquatic birds in Japan during the 2018/2019 winter season, compared with those during previous winter seasons. Genetic and phylogenetic analyses revealed that AIVs of the same subtypes with multiple genetic constellations were circulating in a single overwintering site during a single winter season. These findings indicate that our improved isolation method contributes to enhance environmental water‐targeted surveillance and to a better understanding of AIV ecology in migratory aquatic bird populations by monitoring ongoing AIV circulation. [ABSTRACT FROM AUTHOR]

Herein, a novel electrothermal desolvation (ED) introduction approach is developed to enhance the analytical sensitivity of the point discharge (PD)-based microplasma-optical emission spectrometric (PD-MIP-OES) system for detecting trace Cd, Zn, Pb and Mn in environmental water samples. Liquid samples are converted into aerosols through a miniature ultrasonic nebulizer, and subsequently desolvated by electric heating at 350 °C. The analytes obtained after condensation (referring to the smaller apertures aerosols and volatile analytes after ED and condensation) are excited and detected by PD-MIP-OES. For a 160 μL liquid sample, analysis is completed within 10 s, achieving a desolvation efficiency of 93 %. Under the optimized conditions, the detection limits for Cd, Zn, Pb and Mn are 1.3, 1.2, 2.4 and 2.1 μg L−1, respectively. Compared to traditional direct ultrasonic nebulization introduction, sensitivity increases by 17, 12, 10 and 14 times, respectively. The accuracy and practicality of the proposed method are verified by measuring certified reference material and several real water samples. The ED-enhanced PD-MIP-OES device presented is compact, easy to operate, and capable of rapid analysis, which provides a convenient and reliable tool for the field analysis of Cd, Zn, Pb and Mn in environmental water samples. [Display omitted] • A novel electrothermal desolvation (ED) introduction approach is proposed. • The ED-enhanced PD-OES device achieved a desolvation efficiency of up to 93 %. • Detection sensitivity increases by 10–17 times compared with direct ultrasonic nebulization introduction. [ABSTRACT FROM AUTHOR]

In this study, a spent mushroom substrate (SMS) from Lentinus edodes cultivation was used to prepare biochar (BC) and magnetic biochar (MBC) at high temperatures. The magnetic field strength of MBC was proved via VSM analysis. The results of the nitrogen adsorption‒desorption isotherms of BC and MBC showed that MBC exhibited stronger adsorption, and SEM was performed to compare the microstructures of BC and MBC. TEM was performed to compare the distributions of C, O, and Fe. The FT-IR and XRD results revealed changes in the structure and the formation of new substances after magnetization; that is, MBC was more conducive to the adsorption and recovery of pesticides. Moreover, a method for the detection of tetramethrin, beta-cypermethrin, and fenvalerate in water samples (tap water, lake water, and river water) was established, and this method combined the use of MBC as adsorbent and high-performance liquid chromatography. Moreover, great linearity of the method was obtained in the range of 0.5–2.5 μg/mL; the recoveries in real samples were in the range of 70.20–73.32 %, and the RSDs were in the range of 0.22–1.09 %. The method is simple and effective, is suitable for the detection of pyrethroids in water, and has certain application potential. [Display omitted] • Magnetic biochar (MBC) prepared by waste fungus slag could be applied as adsorbent. • MBC is suitable for the adsorption of pyrethroid in water samples. • Structural analysis proved that MBC was more suitable as an adsorbent than BC. • Pyrethroid adsorption method forwater samples has been established using MBC. • The study is helpful to broaden the utilization range of agricultural waste. [ABSTRACT FROM AUTHOR]

• Import pyrazine into benzene skeletons to establish hydrophilic-lipophilic balance. • The amphiphilic polymer was fabricated on a Fe3O4 sphere for magnetic extraction. • The magnetic composite extracts multiple analytes with varying polarities simultaneously. Under the principle of similar compatibility, researchers have developed various polarity extractants corresponding to a class of chemicals. Separating different polarities chemicals with one extractant effectively has become a novel research trend in separation science. Given the complexity of environmental sample matrices and the significant differences in polarity and solubility of various compounds, the introduction of hydrophilic groups to hydrophobic material skeletons can lead to sorbents with hydrophilic-lipophilic balance (HLB) property and thus improve their extraction performance for substances with different polarities. In this work, a hypercrosslinked polymer (HCP Pz-TPB), designated as HLB, was synthesized by incorporating polar pyrazine and nonpolar triphenylbenzene molecules within each other. Subsequently, a core-shell magnetic composite material was obtained by encapsulating magnetic Fe 3 O 4 nanoparticles in HCP Pz-TPB. The material was applied as an adsorbent for magnetic solid phase extraction (MSPE) and combined with a high-performance liquid chromatography-photodiode array detector (HPLC-PDA) to enrich, separate, and detect seven polar contaminants in environmental water samples. The proposed approach, Fe 3 O 4 @SiO 2 @HCP Pz-TPB −MSPE-HPLC-PDA, is characterized by its outstanding high sensitivity, low detection limits, wide linear range, and good reproducibility. The method demonstrated satisfactory linearity in the range of 0.05–2 μg mL-1 with R2 values between 0.9969 and 0.9997; the limits of detection (LOD) were observed to be within the range of 0.0019–0.016 μg L-1, and limits of quantification (LOQ) was observed to be within the range of 0.0064–0.054 μg L-1 range with good precision. The recoveries of the different contaminants in the environmental samples ranged from 83.61 to 116.46% (RSD≤10.56, n = 5). The new hydrophilic-lipophilic balance extractant is highly efficient, sensitive, and precise for extracting different polar pollutants. The findings demonstrate that the Fe 3 O 4 @SiO 2 @HCP Pz-TPB display a remarkable affinity for multiple targets, driven by complex interactions including multi-stackings and hydrogen bonding as a sorbent. The synthesized Fe 3 O 4 @SiO 2 @HCP Pz-TPB may be employed in diverse applications, including extraction, removal, and determination of diverse trace multi-target analytes in complex media. [ABSTRACT FROM AUTHOR]

Methoxy-DDT is an organochlorine pesticide extensively used in agricultural practices as a DDT substitute. Methoxy-DDT has been found and quantified in several investigations in groundwater, drinking water, sediment, and various biota. Therefore, designing efficient and cost-effective adsorbents for removing methoxy-DDT is vital. In this work, we embedded Ficus benghalensis L. derived carbon dots (CDs) in mesoporous silica (MS) to fabricate MS-CDs nanohybrid material. MS-CDs nanohybrid exhibited remarkable selectivity and removal efficiency towards methoxy-DDT, outperforming other endocrine disruptors. Parameters for industrial-scale fixed-bed adsorption columns, such as bed capacity, length, and breakthrough times, were analyzed. The kinetic study revealed that pseudo-second-order (PSO) adsorption and isotherm analysis confirmed the Langmuir model as the best fit. Small bed adsorption (SBA) column analysis was carried out using spiked Yamuna river water, and the breakthrough curves were demonstrated by varying MS-CDs bed height. The maximum adsorption capacity obtained for methoxy-DDT was 17.16 mg/g at breakthrough and 49.98 mg/g at exhaustion. The adsorbent showed 86.53% removal efficiency in the 5th cycle, demonstrating good reusability. These results indicate that the developed material MS-CDs-based organic sphere is an effective adsorbent for aqueous methoxy-DDT adsorption and can be applied to wastewater treatment. [Display omitted] • Novel synthesis of self-assembled mesoporous silica-decorated biogenic carbon dots. • Efficient removal of methoxy-DDT from river water using MS-CDs nanohybrid. • Adsorption kinetics and thermodynamics of methoxy-DDT on MS-CDs were studied. • Short-scale fixed-bed adsorption parameters were examined. • High adsorption capacity (17.16 mg/g at breakthrough) was achieved for methoxy-DDT. [ABSTRACT FROM AUTHOR]

• cLAMP was less analytically sensitive than qPCR by two orders of magnitude. • Both qPCR and cLAMP assays had a host sensitivity value of 1.00 in untreated sewage. • LAMP's host specificity was higher than qPCR, with values of 0.81 and 0.64 respectively. • Both methods detected HF183 in environmental water samples with moderate agreement. • LAMP could be a rapid, sensitive method for detecting sewage pollution in environmental waters. Surface waters are vulnerable to contamination by human and animal feces, posing risks to human health due to potential exposure to enteric pathogens. This research developed a colorimetric loop-mediated isothermal amplification (cLAMP) assay to detect sewage associated Bacteroides dorei HF183/BacR287 (HF183) marker in wastewater and environmental water samples. The host sensitivity and host specificity of the assay were evaluated, and their performance was compared to the Bacteroides HF183 qPCR assay using control materials (gBlocks), environmental water samples seeded with untreated sewage, and ambient environmental water samples. In serial dilutions of control materials, qPCR produced quantifiable data across all dilutions, while cLAMP detected the marker down to 0.001 pg/µL of control materials, which was two orders of magnitude less sensitive than qPCR. All untreated sewage samples (n = 12) tested positive for HF183 by both the qPCR and cLAMP assays, demonstrating a host sensitivity value of 1.00 (maximum value of 1.00). The host specificity by analysing 70 non-human fecal nucleic acid samples revealed cLAMP's specificity value of 0.81 compared to qPCR's 0.64. When testing sewage-seeded environmental water samples, both methods detected HF183 for the lowest amount of sewage, indicating similar detection sensitivity. The application of cLAMP for tracking sewage pollution in environmental waters showed promising results, with moderate agreement between cLAMP and qPCR (κ = 0.510). However, cLAMP occasionally missed detections compared to qPCR, particularly in low-concentration samples. Overall, the cLAMP HF183 assay demonstrated promising potential as a rapid and sensitive method for detecting sewage pollution, offering a viable alternative to qPCR in certain environmental monitoring scenarios. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, a novel technique utilizing vortex-assisted dispersive liquid-liquid microextraction with magnetic deep eutectic solvents (MDESs) was established and coupled with HPLC-UV to analyze six primary aromatic amines (PAAs). A novel hydrophobic MDES prepared from trioctylphosphine oxide, octanol, and CoCl 2 was used as the extractant, which could be dispersed uniformly during extraction, then floated onto the sample surface and re-aggregated into a single drop spontaneously after the extraction. The variables influencing the efficiency of the extraction process were investigated. When performing under the optimal extraction conditions, this method exhibited excellent linearity, low limits of detection (0.2–0.9 ng mL−1), and high precision (RSD ≤ 8.3 %). The enrichment factors ranged from 56 to 182. Satisfactory recoveries in the range of 91.6–109.2 % with RSDs < 7.1 % were obtained from three apple juices and three environmental water samples. The greenness and practicality of the developed method were assessed by AGREE, AGREEprep, and blue applicability grade index metric tools. Overall, the established procedure demonstrated its simplicity, speediness, environmental friendliness, and effectiveness in analyzing PAAs from aqueous matrices. [Display omitted] • A series of hydrophobic magnetic deep eutectic solvents (HMDESs) were synthesized. • The physicochemical and thermal properties of synthesized HMDESs were characterized. • A vortex-assisted HMDES-based DLLME method was developed. • The proposed method is simple, fast, robust, cost-effective, eco-friendly and highly sensitive. • This method realizes simultaneous pre-concentration of 6 primary aromatic amines from juice and water matrices. [ABSTRACT FROM AUTHOR]

Fluoroquinolones (FQs) are widely used for their excellent antimicrobial properties, yet their release into aquatic environments pose risks to ecosystems and public health. The accurate monitoring and analysis of FQs present challenges due to their low concentrations and the complex matrices found in actual environmental samples. To address the need for auto-pretreatment and on-line instrumental analysis, developing new microextraction materials and protocols is crucial. Such advancements will provide better analytical assurance for the effective extraction and determination of FQs at trace levels, which is of great significance to environmental protection and human health. In this work, we presented a Co2+ mediated paper-based molecularly imprinted polymer chip (CMC@Co-MIP), combined with UPLC analysis, to develop an effective analytical method for identifying and quantifying trace amounts of ciprofloxacin (CIP) and enrofloxacin (ENR) in water samples. Notably, the addition of Co2+ in CMC@Co-MIP helped to capture the template molecule CIP through coordination before imprinting, which significantly improved the ordering of the imprinted cavities. CMC@Co-MIP exhibited a maximum adsorption capacity up to 500.20 mg g−1 with an imprinting factor of 4.12, surpassing previous reports by a significant margin. Furthermore, the enrichment mechanism was extensively analyzed by various characterization techniques. The developed method showed excellent repeatability and reproducibility (RSD < 13.0 %) with detection limits ranging from 0.15 to 0.21 μg L−1 and recoveries ranging from 64.9 % to 102.3 % in real spiked water samples. We developed a novel microextraction paper-based chip based on Co2+ mediation, which effectively improved the selectivity and convenience of extracting FQs. This breakthrough allowed the chip to have a high enrichment efficiency as well as provide a robust on-line instrumental program. It also confirms that the imprinting scheme based on metal ion coordination is a high-performance strategy. [Display omitted] • A novel paper-based molecularly imprinted polymer chip (CMC@Co-MIP) was synthesized. • The imprinting protocol based on metal coordination was a high-performance strategy. • The chip showed excellent adsorption of fluoroquinolones, reaching 500.20 mg g−1. • The chip exhibited potentiality for environmental water samples pretreatment. [ABSTRACT FROM AUTHOR]

In 2018, a large, coordinated environmental flow was instituted along the Barwon‐Darling (Barka) River to connect ecosystems and restore public confidence in water regulation in the Murray‐Darling Basin. This article examines the multiple river realities enacted by this event—environmental flow, regulated flow, unregulated flow, shut‐up flow—as a conflict over what constitutes the character of water during substantial change in Australia's settler colonial systems of water governance. Geographical analyses of event spaces from military contexts assisted in unpacking the ontological and spatio‐temporal matters germane to this situation in which managers needed to heed the dynamism of the river at both material and institutional registers. The article describes the scientific and regulatory practices and visual technologies through which management of an "event‐ful" river brought together some waters (but not others) into something ontologically secure and coherent, and therefore governable. It shows how the naturalising discourse constrained and enabled what could be said about the relations deserving of water and who gets to decide what socio‐material connections water might make. Aboriginal leaders interviewed during the flow chose to emphasise a wider relational set of connections than did state water managers, and to accentuate dysfunctional and destructive relations, thereby inviting others to think and feel differently about environmental flows. [ABSTRACT FROM AUTHOR]

In this study, an in situ synthesis approach based on electrochemical reduction and ion exchange was employed to detect carbaryl species using a disposable, screen-printed carbon electrode fabricated with nanocomposite materials. Reduced graphene oxide (rGO) was used to create a larger electrode surface and more active sites. Gold nanoparticles (AuNPs,) were incorporated to accelerate electron transfer and enhance sensitivity. A cation exchange Nafion polymer was used to enable the adhesion of rGO and AuNPs to the electrode surface and speed up ion exchange. Cyclic voltammetry (CV), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), electrical impedance spectroscopy (EIS), atomic force microscopy (AFM) and scanning electron microscopy (SEM) were performed to study the electrochemical and physical properties of the modified sensor. In the presence of differential pulse voltammetry (DPV), an rGO/AuNP/Nafion-modified electrode was effectively used to measure the carbaryl concentration in river and tap water samples. The developed sensor exhibited superior electrochemical performance in terms of reproducibility, stability, efficiency and selectivity for carbaryl detection with a detection limit of 0.2 µM and a concentration range between 0.5µM and 250 µM. The proposed approach was compared to capillary electrophoresis with ultraviolet detection (CE-UV). [ABSTRACT FROM AUTHOR]

In this study, a new method for the determination of fipronil and its three metabolites in environmental water samples was developed based on meltblown nonwoven fabric solid‐phase extraction combined with gas chromatography‐electron capture detection. As the core material of medical masks, meltblown nonwoven fabric is made of polypropylene superfine fibers which are randomly distributed and bonded together with a relatively large specific surface area and good permeability. Polypropylene as a high molecular hydrocarbon‐based polymer has the characteristics of good hydrophobicity and lipophilicity, which can be applied for the separation and enrichment of hydrophobic substances in food, environment, and biological samples. The meltblown nonwoven fabric is soft and can fill the solid‐phase extraction cartridge tightly. This aspect also makes it suitable to be used as an ideal solid‐phase extraction sorbent. A series of parameters influencing the extraction efficiency were investigated, and under the optimized conditions, fipronil and its three metabolites had a good linear relationship in the range of 0.2–100 μg/L with a correlation coefficient R2 of more than 0.999. The recoveries at three spiked concentrations were in the range of 99.2–107.3% with the relative standard deviations less than 9.8% (intra‐day) and 8.1% (inter‐day). The limit of detection for the four target analytes was in the range of 0.02–0.06 μg/L. Finally, this method was successfully applied in the analysis of fipronil and its three metabolites in various types of environmental water samples. [ABSTRACT FROM AUTHOR]

An effective magnetic solid‐phase extraction method was proposed using magnetic graphene oxide coated with poly(2‐aminoterephthalic acid‐co‐aniline) as a sorbent for preconcentration and extraction of organophosphorus pesticides from environmental water and apple juice samples, and determined using the gas chromatography‐mass spectrometry analysis. To approve the successful synthesis of the magnetic nanocomposite, the prepared sorbent was characterized by field emission scanning electron microscopy, X‐ray diffraction, vibrating sample magnetometer, and Fourier transforms infrared techniques. The main parameters affecting the extraction efficiency were considered and studied to afford an optimized procedure. Systematic method validation verified its suitable recoveries (89.4–107.3%), and precision (relative standard deviations < 6.8%). The method showed a wide linear dynamic range (0.04–700 ng/mL) with low limits of detection (0.01–0.06 ng/mL) and quantification (0.04–0.21 ng/mL). This method presented good potential and great sensitivity for the pesticides determination. [ABSTRACT FROM AUTHOR]

Globally, wetlands have experienced significant declines in area and condition. Reedbeds are a key attribute of many wetlands and are typically composed of Phragmites australis (common reed), a globally distributed emergent aquatic perennial grass. Environmental water is increasingly used to support functioning river and floodplain ecosystems, including reedbeds, where maintaining wetland vegetation condition is a common objective. Drone-based remote sensing allows for the consistent collection of high-quality data in locations such as wetlands where access is limited. We used unoccupied aerial vehicles (UAVs) and convolutional neural networks (CNNs) to estimate the cover of Phragmites australis and examine the role of reedbed condition and prior environmental watering in the response of reedbeds to flooding. Data were collected from a large inland reedbed in semi-arid western New South Wales, Australia between October 2019 and March 2021 using UAVs and processed using CNNs. Prior to the flood event, sites that had received environmental water had a significantly greater cover of Phragmites australis. The sites that were not managed with environmental water had very low cover (<1%) of reeds prior to the flood event and transitioned from a Critical condition to a Poor or Medium condition following flooding. Using UAVs and CNNs we demonstrated the role environmental water plays in filling the gaps between large flood events and maintaining the condition and resilience of reedbeds. [ABSTRACT FROM AUTHOR]

The residues and abuse of antibiotics have seriously endangered ecological balance and human health; meanwhile, antibiotics determination is very difficult because of their low levels and multiple categories in complicated matrices. Appropriate sample pretreatment is usually imperative to enrich (ultra)trace antibiotics and eliminate matrix interference prior to chromatographic analysis. Dispersive liquid-liquid microextraction (DLLME) has become an ideal pretreatment technique owing to its simplicity, effectiveness, low-consumption, etc. In this work, an ultrasonic-assisted DLLME (UA-DLLME) was developed for the simultaneous extraction of seven sulfonamides (SAs) antibiotics in environmental water and seafood samples coupled with HPLC-DAD determination. Several parameters affecting UA-DLLME efficiency were systematically optimized, and consequently the SAs were separated and detected within 14.5 min. The obtained limits of detection (LODs) and limits of quantification (LOQs) ranged from 0.7–7.8 μg/L and 2.4–26.0 μg/L for three water samples (seawater, aquaculture wastewater and lake water) and two seafood samples (pomfrets and shrimps). High recoveries (80.0–116.0%) with low relative standard deviations (0.1–8.1%) were achieved for all the tested samples at three spiked levels. Notably, sulfadimethoxine was found at 24.49 μg/L in one seawater sample. The facile, robust and benign DLLME-HPLC method demonstrated promising perspectives for multiresidue analysis of antibiotics. [ABSTRACT FROM AUTHOR]

A novel fluorescence platform was fabricated for enrofloxacin determination by using cDNA-modified dipeptide fluorescence nanoparticles (FDNP-cDNA) and aptamer-modified magnetic Fe3O4 nanoparticles (Fe3O4-Apt). The FDNP were prepared via tryptophan-phenylalanine self-assembling. When magnetic Fe3O4-Apt incubated with standard solution or sample extracts, the target enrofloxacin was selectively captured by the aptamer on the surface of the Fe3O4 nanoparticles. After removing interference by washing with phosphate-buffered saline, the FDNP-cDNA was added, which can bind to the aptamer on the surface of the Fe3O4 nanoparticles not occupied by the analyte. The higher the concentration of the target enrofloxacin in the standard or sample solution is, the less the FDNP-cDNA can be bound with the Fe3O4 nanoparticles, and the more the FDNP-cDNA can be observed in the supernatant. Fluorescence intensity (Ex/Em = 310/380 nm) increased linearly in the enrofloxacin concentration range 0.70 to 10.0 ng/mL with a detection limit of 0.26 ng/mL (S/N = 3). Good recoveries (88.17–99.30%) were obtained in spiked lake water, chicken, and eel samples with relative standard deviation of 2.7–6.2% (n = 3). [ABSTRACT FROM AUTHOR]

Growing concerns related to antibiotic residues in environmental water have encouraged the development of rapid, sensitive, and accurate analytical methods. Single‐drop microextraction has been recognized as an efficient approach for the isolation and preconcentration of several analytes from a complex sample matrix. Thus, single‐drop microextraction techniques are cost‐effective and less harmful to the environment, subscribing to green analytical chemistry principles. Herein, an overview and the current advances in single‐drop microextraction for the determination of antibiotics in environmental water are presented were included. In particular, two main approaches used to perform single‐drop microextraction (direct immersion‐single‐drop microextraction and headspace‐single‐drop microextraction) are reviewed. Furthermore, the impressive analytical features and future perspectives of single‐drop microextraction are discussed in this review. [ABSTRACT FROM AUTHOR]