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Pharmaceutically active compounds (PhACs) are widely used in medical treatments but pose risks to ecosystems and human health when present in the environment. Understanding their fate in nature is complex and influenced by various factors. Phototransformation, where PhACs change chemically upon light exposure, offers the potential for reducing their environmental levels. Studying this process is crucial for understanding risks, developing safe disposal strategies, and innovating removal methods to mitigate adverse effects. This review delves into the major factors influencing the transformation of PhACs under natural conditions. It provides a comprehensive analysis of the mechanisms involved in the photochemical activity of PhACs, shedding light on their behavior upon exposure to sunlight. Special attention is given to delineating the differences in the phototransformation processes among 13 major pharmaceutical classes. By examining the various factors influencing PhAC transformation and elucidating their mechanisms, this review aims to contribute to a deeper understanding of the fate of pharmaceuticals in the environment. Such insights are invaluable for developing effective strategies to mitigate the risks posed by PhAC contamination and safeguarding environmental and human health.

A simple, efficient, effective, and environmentally friendly partitioned dispersive liquid-liquid microextraction (PDLLME) combined with high performance liquid chromatography – diode array detection (HPLC-DAD) method has been developed for the simultaneous determination of nitrofurans and sulfonamides in water. The type and volume of the extraction solvent, type and volume of disperser solvent, pH, speed and time of vortex, concentration of salt, and centrifugation period were optimized. Under these conditions, enrichment factors between 37.5 and 190.4 were obtained. Good linearity was obtained for sulfaquinoxaline from 5 to 1000 µg L−1 and 5 to 600 µg L−1 for the other analytes, with the coefficients of determination (r2) ranging between 0.9978 and 0.9998. Intra-day and inter-day repeatability expressed as the relative standard deviation were between 1.90 and 8.87% and 2.87 and 9.43%. The limits of detection and quantification were from 0.31 to 0.82 µg L−1 and 0.98 to 2.73 µg L−1, respectively. The method was employed for the analysis of tap, ground, and river water. Recoveries from 89.42 to 108.27% with relative standard deviations from 1.47 to 8.93% were obtained. The developed method was used for monitoring the residues of these antibiotics in drinking and environmental water. [ABSTRACT FROM AUTHOR]

Adenoviruses (AdVs) have a significant impact in both medical and environmental contexts. The objective of this study was to investigate the prevalence of AdV in different water types, such as untreated and treated wastewater, surface water, groundwater, drinking water, and other water matrices. A total of 239 articles were included in this meta-analysis. Adenoviruses were detected in various waters worldwide. The overall prevalence in water was found to be 59.2%, with the highest prevalence in untreated wastewater (83.1%) and treated wastewater (75.3%), followed by "other water matrices" (53.4%), surface water (49.5%) drinking water (22.7%), and groundwater (18.5%). Most of the studies did not assess the viability of the viruses, leading to weak links between water contamination and risk. Both human and animal AdV were found in water environments. The findings suggest that water, including drinking water, could be a significant route of AdV transmission in both developed and developing economies. [ABSTRACT FROM AUTHOR]

Access to clean water, one of the United Nation’s Sustainable Development Goals, is challenged by an increase in the presence of emerging microbial and other contaminants due to urbanization, among other factors. Traditionally, the presence of indicator microorganisms is determined using culturing methods. However, these classical methods cannot be used to determine the identities of ‘unknown’ bacteria and is limited to isolating the culturable state of microorganisms. Thus with culturing, the identities of many bacteria, particularly novel or non-culturable, may remain unknown. The use of a DNA-based method, 16S rRNA next-generation sequencing (NGS), can assist with determining the identities of bacterial populations in a water sample. The objective of this 16S rRNA NGS study was to investigate the bacterial community composition and diversity in a range of water sources. Water samples comprising of potable, surface, ground, marine, aquaculture, rain, wetland and swimming bath water matrices were subjected to 16S rRNA NGS using the Illumina 16S rRNA Metagenomics analysis pipeline. Operational taxonomic units were analysed and the identities of bacterial genera determined. In this study, genera of Acinetobacter, Mycobacterium, Pseudomonas, Legionella, Burkholderia, Yersinia, Staphylococcus and Vibrio were spread across the water matrices. Alpha (within sample) and beta (between samples) diversities for each bacterial community within the tested samples were also determined. [ABSTRACT FROM AUTHOR]

In this study, we developed a method for the on-site selective detection and quantification of microplastics in various water matrices using fluorescence-tagged peptides combined with electrochemical impedance spectroscopy (EIS). Among the types of plastics found in seawater, polystyrene (PS) microplastics were selected. Fluorometry, scanning electron microscopy (SEM), and Raman spectroscopy were used to verify the specific interaction of these peptides with PS spherical particles of different sizes (ranging from 0.1 to 250 µm). Principal component analysis (PCA) was employed to determine the effects of temperature (25–65 °C), incubation time (5 and 10 min), and particle size on plastic-peptide bonding efficiency, based on fluorescence intensity. For each water type (pure, tap, NaCl (0.5 M), and seawater), EIS plots (Nyquist and Bode) were generated. Significant factors affecting the EIS response, including particle size, shape, and material, were analyzed by measuring electrical parameters for different microplastic concentrations (50 ppb to 20 ppm). The EIS parameters changed with increasing plastic concentration, determining a limit of detection (LOD) of 50 ppb (ng/mL) for pure and tap water and 400 ppb for saline water, as the lowest concentration producing a significant change in EIS parameters compared to the baseline. The sensor proved highly effective for detecting microplastics in low ionic strength environments such as pure and tap water. However, in high ionic strength environments like saline and seawater, the detection capability diminished, likely due to the masking effect of ions on the EIS response. [Display omitted] • Developed a method for on-site detection of microplastics using EIS and peptide sensors. • Verified peptide-microplastic interactions using fluorometry, SEM, and Raman spectroscopy. • PCA analyzed the effect of temperature, incubation time, and particle size on bonding efficiency. • Determined detection limits: 50 ppb for pure/tap water, 400 ppb for salty water. • Sensor effective for various microplastics in different water types, despite ionic strength variations. [ABSTRACT FROM AUTHOR]

Water pollution has become a serious environmental issue. The textile industries using textile dyes are considered to be one of the most polluting of all industrial sectors. The application of solar-light semiconductor catalysts in wastewater treatment, among which TiO2 can be considered a prospective candidate, is limited by rapid recombination of photogenerated charge carriers. To address these limitations, TiO2 was tailored with graphitic carbon nitride (g-C3N4) to develop a heterostructure of g-C3N4@TiO2. Herein, a simple hydrothermal synthesis of TiO2@g-C3N4 is presented, using titanium isopropoxide (TTIP) and urea as precursors. The morphological and optical properties and the structure of g-C3N4, TiO2, and the prepared heterostructure TiO2@g-C3N4 (with different wt.% up to 32%), were analyzed by various laboratory methods. The photocatalytic activity was studied through the degradation of methylene blue (MB) aqueous solution under UV-A and simulated solar irradiation. The results showed that the amount of g-C3N4 and the irradiation source are the most important influences on the efficiency of MB removal by g-C3N4@TiO2. Photocatalytic degradation of MB was also examined in realistic conditions, such as natural sunlight and different aqueous environments. The synthesized g-C3N4@TiO2 nanocomposite showed superior photocatalytic properties in comparison with pure TiO2 and g-C3N4, and is thus a promising new photocatalyst for real-life implementation. The degradation mechanism was investigated using scavengers for electrons, photogenerated holes, and hydroxyl radicals to find the responsible species for MB degradation. [ABSTRACT FROM AUTHOR]

In this study, chalcopyrite (CuFeS2), a natural mineral with a bimetallic structure, was used as the activator to generate radicals for removing organic pollutants from aqueous solutions via the activation of peroxymonosulfate (PMS). Sulfisoxazole (SIX), a sulfonamide antibiotic, was selected as the model pollutant. The results showed that chalcopyrite was highly reactive toward the activation of PMS; under the conditions of 50 µM PMS and 1 g/L chalcopyrite, approximately 95.7% of the SIX was degraded after reaction for only 5 min. An increase in the loading of chalcopyrite (0.25–2 g/L) promoted the degradation of SIX, while elevated levels of PMS (0.05–0.5 mM) slightly retarded the degradation kinetics. Although the best performance was observed under acidic conditions (pHs 3 and 4), near complete degradation of SIX was also achieved at pH 5.5. Identification of reactive species revealed that both a hydroxyl radical and a sulfate radical were formed in chalcopyrite–PMS oxidation, and they were responsible for the degradation of SIX. Trace amounts of copper and iron were leached out from chalcopyrite during the activation, and both the heterogeneous and homogeneous activation of PMS contributed to the generation of oxidizing radicals. Common water constituents including Cl−, HCO 3 − , and natural organic matter at their environmentally relevant levels showed a limited effect on the degradation of SIX, which suggests that chalcopyrite–PMS oxidation has high reactivity and stability in the degradation of organic pollutants and shows great practical application potential. [ABSTRACT FROM AUTHOR]

Carbendazim (CBZ), a widely used fungicide in agriculture, is frequently detected in aquatic environment and causes significant concerns because of its endocrine-disrupting activity. This study investigated the degradation kinetics of CBZ in ferrate (Fe(VI)) oxidation, the influence of water matrices, and the transformation pathways of CBZ. The second-order rate constant for the reaction between CBZ and Fe(VI) decreased from 88.0 M−1·s−1 to 1.6 M−1·s−1 as the solution pH increased from 6.2 to 10.0. The optimum reaction conditions were obtained through response surface methodology, which were pH = 7.8 and [Fe(VI)]/[CBZ] = 14.2 (in molarity), and 96.9% of CBZ could be removed under such conditions. Cu2+ and Fe3+ accelerated the degradation of CBZ by Fe(VI) oxidation; common cations and anions found in natural water had no significant effect, while the presence of humic acid also accelerated the degradation of CBZ. Based on the degradation products identified, degradation of CBZ in Fe(VI) oxidation proceeded via three pathways: namely, hydroxylation, removal of the methoxyl group, and cleavage of the C–N/C=N bond. The initial reaction site of CBZ oxidation by Fe(VI) was also supported by the atomic partial charge distribution on the CBZ molecule obtained from density functional theory (DFT) calculations. CBZ in natural water matrices was efficiently removed by Fe(VI) oxidation under near-neutral conditions, indicating that Fe(VI) oxidation could be a promising treatment option for benzimidazole fungicides. [ABSTRACT FROM AUTHOR]

Atrazine is an herbicide represented by a triazine ring substituted with chlorine, ethylamine and isopropylamine, which makes it recalcitrant for biological degradation in environment. Due to be very used in agriculture, mainly in the control of corn crop weeds, it ends up remaining in the environment for a long time and becoming one of the factors responsible for the contamination of soil, air and water. New cheaper detection methods, with less time to analyze and more effective, have been studied to improve the detection of this analyte. The nanotechnology area has shown great advances, such as the development of nanobiosensors through sensor layers, to detect the presence of herbicides in water. Based on these facts, this paper provides a review of the most recent works in nanobiosensor used for atrazine detection, with focus on the applications in water matrices.

The photodegradation of NDMA has been extensively investigated under the irradiation of low‐pressure or medium‐pressure Hg lamps and xenon lamp. However, NDMA photolysis remains unknown under 365 nm ultraviolet light‐emitting diode (UV‐LED) irradiation. This study conducted a comprehensive investigation on NDMA photodegradation by 365 nm UV‐LED illumination. The quantum yield of NDMA photolysis under 365 nm UV‐LED irradiation was determined to be 0.0312 ± 0.0047. The influence of pH on NDMA photodegradation was found to be wavelength dependent. Compared with distilled and deionized water (DDW), tap water inhibited NDMA photodegradation, but secondary wastewater effluent did not. Based on the quantification of NDMA photolysis products and pH influence, the photooxidation of the excited NDMA in the nonprotonated form was proposed to be a major pathway for NDMA photodegradation under the irradiation of UV‐LED lamp at 365 nm. This study further enhances our knowledge on NDMA photodegradation. Practitioner Points: Quantum yield of NDMA photolysis at 365 nm was determined to be 0.0312 ± 0.0047.The influence of pH on NDMA photodegradation was wavelength dependent.NDMA photodegradation was inhibited in tap water compared with that in DDW.NDMA photodegradation in SWE was similar to that in DDW.Excited nonprotonated NDMA photooxidation is a major degradation pathway. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) is responsible for acute hepatitis in humans, through foodborne, zoonotic, and waterborne transmission routes. This study aimed to assess the prevalence of HEV in water matrices. Six categories were defined: untreated and treated wastewater, surface water (river, lake, and seawater), drinking water, groundwater, and other water environments (irrigation water, grey water, reservoir water, flood water, and effluent of pig slaughterhouse). We searched PubMed, Web of Science, Global Index Medicus, and Excerpta Medica Database. Study selection and data extraction were performed by at least two independent investigators. Heterogeneity (I2) was assessed using the χ2 test on the Cochran Q statistic and H parameter. Sources of heterogeneity were explored by subgroup analysis. This study is registered with PROSPERO, number CRD42021289116. We included 87 prevalence studies from 58 papers, 66.4% of which performed in Europe. The overall prevalence of HEV in water was 9.8% (95% CI 6.4–13.7). The prevalence was higher in untreated wastewater (15.1%) and lower in treated wastewater (3.8%) and in drinking water (4.7%). In surface water, prevalence was 7.4%, and in groundwater, the percentage of positive samples, from only one study available, was 8.3%. Overall, only 36.8% of the studies reported the genotype of HEV, with genotype 3 (HEV-3) prevalent (168 samples), followed by HEV-1 (148 sample), and HEV-4 (2 samples). High-income countries were the most represented with 59/87 studies (67.8%), while only 3/87 (3.5%) of the studies were performed in low-income countries. The overall prevalence obtained of this study was generally higher in industrialized countries. Risk of bias was low in 14.9% of the studies and moderate in 85.1%. The results of this review showed the occurrence of HEV in different waters environments also in industrialized countries with sanitation and safe water supplies. While HEV transmission to humans through water has been widely demonstrated in developing countries, it is an issue still pending in industrialized countries. Better knowledge on the source of pollution, occurrence, survival in water, and removal by water treatment is needed to unravel this transmission path. [ABSTRACT FROM AUTHOR]

[Display omitted] • Peanut shell-derived biochars (PSBCs) exhibited great catalytic performance for PAA. • Coexisted H 2 O 2 was unexpected to be an adverse factor in PAA activation. • The surface –OH group was validated to be the key active site for PAA activation. • Directly electron transfer mechanism was revealed in PAA-based AOP. • The HCO 3 − promoted the degradation of ACP. Biochar-based heterogeneous activation of disinfectant peracetic acid (PAA) is an attractive and promising route for micropollutant elimination in water, yet the underlying activation mechanism is still scarce. In this study, PAA was first catalyzed by peanut shell-derived biochar (PSBC) to degrade acetaminophen (ACP). The enhancement of ACP removal was triggered by PAA activation, while the coexisted H 2 O 2 was unexpected to be an adverse factor owing to its occupation of active sites. Higher dosages of PSBC (0–0.30 g/L) and PAA (0–4.0 mM) favored the destruction of ACP, and the activation energy (41.8 kJ/mol) of PSBC/PAA system is lower than that of the thermal or microwave activated PAA system. The experimental results demonstrate that the metastable complex PSBC-PAA* dominated ACP elimination through an electron transfer mechanism. The surface –OH group was validated to be the key active site for PAA activation. Surprisingly, the actual water matrices present a negligible effect and the promotion of HCO 3 − ion on ACP removal was even observed. Based on the identified intermediates, the transformation of ACP was further proposed with the formation of polymeric products via oxidative coupling reactions. The findings not only shed light on the mechanism of PAA activated by the biochar-based catalyst but also contribute to a novel perspective on future PAA studies in contamination remediation. [ABSTRACT FROM AUTHOR]

• DBD/sulfite system was proposed to mitigate membrane fouling and degrade PFOA. • DBD/sulfite system exhibited excellent performance in actual water samples. • The water matrices exhibited inhibitory, facilitative, or insignificant effects. • The presence of •OH, SO 4 • − , e aq − , and • O 2 − effectively mitigated membrane fouling. • The degradation of PFOA was attributed to the existence of •OH, SO 4 • − , and e aq −. The feasibility of utilizing a dielectric barrier discharge (DBD)/sulfite-ultrafiltration system was investigated in various real water bodies, aiming to clarify the mechanism behind alleviating membrane fouling while synchronously degrading perfluorooctanoic acid (PFOA) during the treatment process of Yangtze River water. The results demonstrated that the DBD/sulfite pretreatment exhibited remarkable rates of membrane flux mitigation (>84.10 %) and efficient degradation rates of PFOA (>85.13 %), which decreased with increasing pH from 3.0 to 11.0. The presence of anions, cations, and natural organic matter slightly hindered the membrane fouling mitigation and PFOA degradation by quenching free radicals; however, the addition of SO 4 2− had a negligible impact. The mitigation of membrane fouling was attributed to the significant involvement of various radicals, including hydroxyl radical (•OH), sulfate radical (SO 4 • −), electron ( e − / e aq −), su-peroxide anion radicals (• O 2 −), and other radicals such as SO 3 • − , exhibiting respective contributions of 33.25 %, 28.49 %, 20.56 %, 11.32 %, and 6.39 % in a synergistic redox effect. The pretreatment effectively reduced standard blocking and cake filtration fouling mechanisms by creating a sparse fouling layer on the membrane surface while increasing its roughness. Additionally, the main active species that played a significant role in the degradation of PFOA were identified as SO 4 • − , •OH, and e aq −. These species contributed approximately 43.63 %, 24.39 %, and 20.65 % respectively to the degradation process. By employing mass spectrometry and density functional theory, a proposed pathway for PFOA degradation was established, effectively reducing the toxicity associated with its degradation byproducts. This study provides innovative insights into membrane-based water treatment technologies that effectively tackle both membrane fouling mitigation and PFOA degradation. [Display omitted] [ABSTRACT FROM AUTHOR]

This work developed efficient heterogeneous catalysts for the methylene blue (MB) dye degradation under photo-Fenton-like conditions. The material was modified to incorporate Fe(III) into ZnO, creating Fe/ZnO strucuture, and applied as heterogeneous catalysts at various pH levels. SEM analysis revealed an agglomerated and plate-like morphology of the synthesized catalysts. The enhanced structure facilitated a removal efficiency of 96.2% for MB dye when employing the photo-Fenton-based process using 5.0% Fe/ZnO catalyst. The high removal efficiency is attributed to the synergy between ≡Fe(III) and ≡Zn(II), which promotes the generation of photoradical species through the Fenton effect. Real water matrices served as a source of MB dye contamination, exhibiting minimal interference and achieving ∼100 % of removal. Scavenger studies indicate that •OH and e⁻ are the primary contributors to the high MB dye degradation efficiency. Additionally, the by-products formed after photo-Fenton process exhibit minimal toxicity towards Lactuca sativa L. No Fe(II) ions were leached at the end of the process. Eight cycles of degradation did not cause significant spectral changes in the FTIR analysis, as well as in the XRD patterns, indicating the material efficient and stable structure. [Display omitted] • Fe/ZnO structure was applied as heterogeneous catalysts to produce active species for the MB removal. • ≡Fe(III) and ≡ Zn(II) promoted high generation of radical in photo-Fenton-like process. • The 5.0 % Fe/ZnO catalyst maintained a high removal rate after eight cycles of reuse. • Lactuca sativa L. germination tests showed no toxicity in the water generated after the degradation process. • No Fe(II) ions were leached after the photo-Fenton-like process. [ABSTRACT FROM AUTHOR]

[Display omitted] • ATZ abatement was correlated to ·OH yield and R ct value in synthetic water samples. • ATZ abatement (with excess dosage of HA): ozonation alone > O 3 /H 2 O 2 > O 3 /γ-Al 2 O 3. • DOM competed more O 3 in initial phase in real water samples but less in final phase. • ·OH yield and R ct from DOM and catalyst should be compared before adding catalyst. In this study, surrogate indicators (·OH yield and R ct value) were developed to identify whether homogeneous and heterogeneous catalysts should be added during ozonation of refractory pollutants. The abatement of atrazine (ATZ) was in the order of O 3 /H 2 O 2 process (94 %) > O 3 /γ-Al 2 O 3 process (70 %) > ozonation alone process (55 %) in synthetic water samples at pH 7, which was in agreement with the order of ·OH yield and R ct value. However, the abatement of ATZ during ozonation alone process (0.64–0.62) was higher than O 3 /H 2 O 2 process (0.63–0.60) and O 3 /γ-Al 2 O 3 process (0.48–0.49) in the presence of high dosage of humic acid (HA, 3.38 × 10−1–4.50 × 10−1 mg C/L) at pH 7. The abatement of ATZ was linearly proportional to ·OH yield, whereas it was not linearly proportional to R ct value in the synthetic water samples containing HA at pH7. The abatement of ATZ during ozonation alone process was higher than that during catalytic ozonation process by one-time ozone dosing method in real water. The abatement of ATZ during O 3 /H 2 O 2 process and O 3 /γ-Al 2 O 3 process were higher than that during ozonation alone process by three-time ozone dosing method in real water, which was linearly proportional to ·OH yield and R ct value. The residual DOM in phase III become recalcitrant to ozone, which could be decomposed by catalyst forming ·OH. Overall, this result implies that the comparison of ·OH yield and R ct value between ozone decay by DOM in various water matrices and by catalyst should be concerned before the addition of catalyst during ozonation process was applied in real water. [ABSTRACT FROM AUTHOR]

The deposition of potentially toxic mercury (Hg) in various ecosystems and subsequent entry into the food chain pose serious concerns to the ecosystem, biodiversity, and public health. In terms of toxicity, Hg is considered as a neurotoxin and capable to augment in food chains and bind to the thiol functional entity in living tissue. Moreover, methylated mercury (CH3Hg+) is a highly toxic form of mercury and extremely difficult to remove from living bodies. Mercury methylation is mainly conducted by microbial and/or chemical processes under appropriate conditions. The mechanisms associated with mercury methylation inside the environment, their sources, production/degradation rate, and transport into the living organisms are not well understood. In addition, efficient and sustainable remediation strategies are essential to employ for mercury removal. Therefore, this review signifies a possible mechanism for mercury methylation and its transportation in the environment, including molecular mechanisms and genes associated with microbial-mediated mercury methylation, and identifies the gaps in existing research. The transport of Hg into the human body and associated health risks are given with suitable examples. Moreover, the escalating anthropogenic activities, the rate-limiting factors, and the sustainable remediation strategies implemented for mercury removal from the environment are discussed. This study will provide a scientific base, direction, and progress in future studies.

Abstract Purpose The World Health Organization (WHO) in 2017 classified some carbapenem-resistant Gram-negative bacteria into a critical criterial group for research and development. This study reviews the need to prioritize the water matrices as hotspot in the development and transfer of antibiotic resistance determinants, where future total resistant superbug may emerge. Methods Published articles on Google Scholars, PubMed/Medline Search and other search tools were selected, with special interest in articles published in indexed journals. Search criteria were based on antibiotic resistance, antibiotic resistance determinants and emerging trend in the reported trend of antibiotic resistance among bacteria from water matrices. Results Research reports around the globe have identified carbapenem-resistant Gram-negative bacteria (CRGNB) in water matrices. These CRGNB have also been found to be resistant to other antibiotics in the last line of defence. Molecular typing of some carbapenem-resistant Enterobacteriaceae (CRE) in the environment through pulsed-field electrophoresis showed them to be the same as those in the hospital settings. CRGNB from various water matrices have been reported to harbour carbapenem resistance genes with phenotypic expression of carbapenemases’ production. Water habitat provides a conducive environment for the development and spread of carbapenem resistance. Factors like residual antibiotics (RAbs), metals, biocide and water-borne mutagens aid the emergence of the resistance in water matrices. Irrespective of where it was contacted, carbapenem-resistant bacteria have poor prognosis. This is exemplified by resistance to 26 different antibiotics recently in the USA. The human health risk associated with the use of water harbouring these pathogens for irrigating fruits and vegetables may be alarming. Conclusion The reports of the rising trend of antibiotic resistance also necessitate prioritizing water matrices when addressing the problems from the reservoir. Surveillance and strict isolation, education and enlightenment, strict compliance with multiple barrier approach of the WHO and more search for more potent antibiotics remain some of the antidotes against the development and spread of resistance through the water matrices as discussed in this article.

Evidently, the emergence of novel coronavirus disease (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has rapidly blowout across the world. Since, the presence of coronaviruses, including SARS-CoV-2 in the fecal specimens and anal swabs of some infected patients, has raised emerging concern with the likelihood of fecal-based spread must be inspected and clarified. Therefore, herein, an effort has been made to spotlight the current scenarios and possible solutions to better understand the risks associated with the wastewater matrices as a potential source of SARS-CoV-2 transmission in the environment. The information reviewed here constitutes a paramount intellectual basis to sustenance ongoing research to tackle the SARS-CoV-2 issue. Thus, this overview indicates the most accessible frontiers related to the detection, quantification, and possible transmission of SARS-CoV-2 in the environment through water routes. The regulatory authorities and policymakers must assure the society via dissemination of evidence-based guidelines that the water matrices, including groundwater and drinking water resources are safe. Finally, we have identified and enlisted a number of pressing questions concerning the ongoing SARS-CoV-2 transmission or COVID-19 emergence issue that must be carefully answered to put further and deeper insight into SARS-CoV-2/COVID-19 in future studies.

The deposition of potentially toxic mercury (Hg) in various ecosystems and subsequent entry into the food chain pose serious concerns to the ecosystem, biodiversity, and public health. In terms of toxicity, Hg is considered as a neurotoxin and capable to augment in food chains and bind to the thiol functional entity in living tissue. Moreover, methylated mercury (CH 3 Hg+) is a highly toxic form of mercury and extremely difficult to remove from living bodies. Mercury methylation is mainly conducted by microbial and/or chemical processes under appropriate conditions. The mechanisms associated with mercury methylation inside the environment, their sources, production/degradation rate, and transport into the living organisms are not well understood. In addition, efficient and sustainable remediation strategies are essential to employ for mercury removal. Therefore, this review signifies a possible mechanism for mercury methylation and its transportation in the environment, including molecular mechanisms and genes associated with microbial-mediated mercury methylation, and identifies the gaps in existing research. The transport of Hg into the human body and associated health risks are given with suitable examples. Moreover, the escalating anthropogenic activities, the rate-limiting factors, and the sustainable remediation strategies implemented for mercury removal from the environment are discussed. This study will provide a scientific base, direction, and progress in future studies. [ABSTRACT FROM AUTHOR]

Purpose: The World Health Organization (WHO) in 2017 classified some carbapenem-resistant Gram-negative bacteria into a critical criterial group for research and development. This study reviews the need to prioritize the water matrices as hotspot in the development and transfer of antibiotic resistance determinants, where future total resistant superbug may emerge. Methods: Published articles on Google Scholars, PubMed/Medline Search and other search tools were selected, with special interest in articles published in indexed journals. Search criteria were based on antibiotic resistance, antibiotic resistance determinants and emerging trend in the reported trend of antibiotic resistance among bacteria from water matrices. Results: Research reports around the globe have identified carbapenem-resistant Gram-negative bacteria (CRGNB) in water matrices. These CRGNB have also been found to be resistant to other antibiotics in the last line of defence. Molecular typing of some carbapenem-resistant Enterobacteriaceae (CRE) in the environment through pulsed-field electrophoresis showed them to be the same as those in the hospital settings. CRGNB from various water matrices have been reported to harbour carbapenem resistance genes with phenotypic expression of carbapenemases’ production. Water habitat provides a conducive environment for the development and spread of carbapenem resistance. Factors like residual antibiotics (RAbs), metals, biocide and water-borne mutagens aid the emergence of the resistance in water matrices. Irrespective of where it was contacted, carbapenem-resistant bacteria have poor prognosis. This is exemplified by resistance to 26 different antibiotics recently in the USA. The human health risk associated with the use of water harbouring these pathogens for irrigating fruits and vegetables may be alarming. Conclusion: The reports of the rising trend of antibiotic resistance also necessitate prioritizing water matrices when addressing the problems from the reservoir. Surveillance and strict isolation, education and enlightenment, strict compliance with multiple barrier approach of the WHO and more search for more potent antibiotics remain some of the antidotes against the development and spread of resistance through the water matrices as discussed in this article. [ABSTRACT FROM AUTHOR]

Enzyme immobilization on solid support offers advantages over free enzymes by overcoming characteristic limitations. To synthesize new stable and hyperactive nano-biocatalysts (co-precipitation method), ginger peroxidase (GP) was surface immobilized (adsorption) on ZnO/SnO 2 and ZnO/SnO 2 /SA nanocomposite with immobilization efficacy of 94 % and 99 %, respectively. Thereafter, catalytic and biochemical characteristics of free and immobilized GP were investigated by deploying various techniques, i.e., FTIR, PXRD, SEM, and PL. Diffraction peaks emerged at 2θ values of 26°, 33°, 37°, 51°, 31°, 34°, 36°, 56°, indicating the formation of SnO 2 and ZnO. The O H stretching of the H 2 O molecules was attributed to broad peaks between 3200 and 3500 cm−1, whereas ZnO/SnO 2 spikes occurred in the 1626–1637 cm−1 range. Sn O stretching mode and Zn O terminal vibrational patterns have been verified at corresponding wavelengths of 625 cm−1 and 560 cm−1. Enzyme entrapment onto substrate was verified via interactions between GP and ZnO/SnO 2 /SA as corroborated by signals beneath 1100 cm−1. GP-immobilized fractions were optimally active at pH 5, 50 °C, and retained maximum activity after storage of 4 weeks at −4 °C. Kinetic parameters were determined by using a Lineweaver-Burk plot and V max for free GP, ZnO/SnO 2 /GP and ZnO/SnO 2 /SA/GP with guaiacol as a substrate, were found to be 322.58, 49.01 and 11.45 (μM/min) respectively. A decrease in values of V max and K M indicates strong adsorption of peroxidase on support and maximum affinity between nano support and enzyme, respectively. For environmental remediation, free ginger peroxidase (GP), ZnO/SnO 2 /GP and ZnO/SnO 2 /SA/GP fractions effectively eradicated highly intricate dye. Multiple scavengers had a significant impact on the depletion of the dye. In conclusion, ZnO/SnO 2 and ZnO/SnO 2 /SA nanostructures comprise an ecologically acceptable and intriguing carrier for enzyme immobilization. [Display omitted] [ABSTRACT FROM AUTHOR]

Among the advanced oxidation processes (AOPs), the Fenton reaction has attracted much attention in recent years for the treatment of water and wastewater. This review provides insight into a particular variant of the process, where soluble Fe(II) salts are replaced by zero-valent iron (ZVI), and hydrogen peroxide (H2O2) is replaced by persulfate (S2O82−). Heterogeneous Fenton with ZVI has the advantage of minimizing a major problem found with homogeneous Fenton. Indeed, the precipitation of Fe(III) at pH > 4 interferes with the recycling of Fe species and inhibits oxidation in homogeneous Fenton; in contrast, suspended ZVI as iron source is less sensitive to the increase of pH. Moreover, persulfate favors the production of sulfate radicals (SO4•−) that are more selective towards pollutant degradation, compared to the hydroxyl radicals (•OH) produced in classic, H2O2-based Fenton. Higher selectivity means that degradation of SO4•−-reactive contaminants is less affected by interfering agents typically found in wastewater; however, the ability of SO4•− to oxidize H2O/OH− to •OH makes it difficult to obtain conditions where SO4•− is the only reactive species. Research results have shown that ZVI-Fenton with persulfate works best at acidic pH, but it is often possible to get reasonable degradation at pH values that are not too far from neutrality. Moreover, inorganic ions that are very common in water and wastewater (Cl−, HCO3−, CO32−, NO3−, NO2−) can sometimes inhibit degradation by scavenging SO4•− and/or •OH, but in other cases they even enhance the process. Therefore, ZVI-Fenton with persulfate might perform unexpectedly well in some saline waters, although the possible formation of harmful by-products upon oxidation of the anions cannot be ruled out.

A 3D printed solid-phase extraction (SPE) device for uranium(VI) extraction has been fabricated using stereolithographic 3D printing. The 3D printed device is shaped as a stirred reactor chamber containing a network of small cubes, which were impregnated with TEVA resin for the extraction of U(VI) from water matrices without doing any previous pretreatment. A flow-through system was combined with off-line ICP-MS detection for the accurate and rapid determination of U(VI) at trace levels. The automatic system was satisfactorily optimized using experimental design, obtaining 0.03 and 0.09 ng U(VI) of detection and quantification limits, respectively, and a durability of 11 consecutive extractions. The reliability of the proposed system was confirmed through the analysis of a reference water material (CSN/CIEMAT 2011), and to water samples (tap, mineral and groundwater) by addition/recovery assays obtaining recoveries between 95 and 106%. This study present for the first time the design of a 3D printing SPE device impregnated with TEVA resin for the on-line extraction of U(VI), showing that 3D printing is a powerful tool for simplifying the construction of complex experimental devices and its operation in analytical procedures for pretreatment applications in water matrices. Image 1 • 3D printed SPE device coated with TEVA resin allows the on-line uranium extraction. • Integration of a 3D printed device in a flow system allows the automatic and safety radioactive samples analysis. • Water matrices were analyzed without any pretreatment. [ABSTRACT FROM AUTHOR]

Abstract Owing to the ease and effectiveness of removing suspended substances (SSs), filtration has become a universal pretreatment step during water sample preparation. However, it can lead to the underestimation of contaminants if the targets easily associate with the SSs or filters. For the first time, this study comprehensively assessed issues related to filtration for the accurate quantification of 35 typical pharmaceuticals, including 28 antibiotics and seven non-steroidal anti-inflammatory drugs (NSAIDs), in water samples by comparing the effects of different filter materials, preservatives, and water matrices on the recoveries. The results showed that some sulfonamides and NSAIDs had an affinity for nylon filters, whereas trimethoprim and macrolides were easily retained on mixed cellulose ester filters. The use of glass fiber filter (0.7 μm) resulted in improved recovery of all the targets. Acidification promoted the adsorption of fluoroquinolones, tylosin, and roxithromycin on SSs, whereas 5% methanol resulted in desorption of macrolides from the SSs and other pharmaceuticals (sulfadiazine, trimethoprim, etc.) from the solid-phase extraction cartridges. Without additional detection of targets adsorbed on the SSs and filters, the addition of appropriate surrogates prior to filtration can help correct the loss. Graphical abstract Unlabelled Image Highlights • Issues relating to filtration for accurate detection of 35 drugs are first studied. • NSAIDs and macrolides readily interact with nylon and cellulose filters, respectively. • Fluoroquinolones, tylosin, and roxithromycin are affected by acidification. • Surrogates are recommended to be used before filtration in surface water analysis. [ABSTRACT FROM AUTHOR]

Abstract In this study, a favorable CO 3 2−/PMS system for efficient degradation of organic contaminants (acid orange 7 (AO7), acetaminophen, para -aminobenzoic acid, phenol, methylene orange, methylene blue) in water was firstly reported. Under optimal conditions, the decolorization ration of AO7 was 100% within 40 min. Data fitting showed that the AO7 decolorization could be described by the pseudo-first-order kinetics, and the rates constant values ranging from 0.0006 to 0.2297 min−1 depending on the operating parameters (initial PMS, CO 3 2−, AO7 concentrations). Radical scavenging studies revealed that superoxide anion radical (O 2 −) and singlet oxygen (1O 2) rather than sulfate (SO 4 −) nor hydroxyl (HO) were the dominant oxidants might be responsible for AO7 degradation. The presence of NO 3 −, HPO 4 2− and low concentration of Cl−, NO 2 −, HCO 3 −, H 2 PO 4 −, HA had no significantly effect on the decolorization of AO7. Adding a higher Cl− concentration displayed favorable effects on the removal efficiencies of AO7, but adding a higher NO 2 −, HCO 3 −, H 2 PO 4 − and HA concentration apparently inhibited this process. The decolorization of AO7 was lower in wastewater in comparison to other natural waters and ultrapure water, which was probably due to the presence of higher concentration of colloids in wastewater. Nevertheless, up to 94.8%, 97.0% and 85.1% of AO7 were degraded from the filtrate, permeate, and retentate phases of wastewater within 60 min, respectively. Consequently, CO 3 2−/PMS would be promising for removal methodology for AO7 in wastewater containing considerable colloids. Finally, three intermediates were identified and degradation pathways of AO7 were proposed. Graphical abstract Unlabelled Image Highlights • CO 3 2−/PMS system was first applied in the organic pollutants degradation. • O 2 − and 1O 2 were the dominant oxidants in the CO 3 2−/PMS system. • AO7 was efficiently degraded in real wastewater containing lots of colloids. • The activation mechanisms of PMS and reaction pathways of AO7 were proposed. [ABSTRACT FROM AUTHOR]

• Generation paths of reactive species (RSs) in different UV-ATPs are reviewed. • This features the first comparison of RSs concentrations in different UV-ATPs. • The effects of water matrix on RSs generation and consumption are discussed. • The reactivities of primary and secondary RSs toward OMPs are summarized. • The degradation efficiencies of different UV-ATPs toward OMPs are compared. The presence of organic micropollutants (OMPs) in water has been threatening human health and aquatic ecosystems worldwide. Ultraviolet-based advanced treatment processes (UV-ATPs) are one of the most effective and promising technologies to transform OMPs in water; therefore, an increasing number of emerging UV-ATPs are proposed. However, appropriate selection of UV-ATPs for practical applications is challenging because each UV-ATP generates different types and concentrations of reactive species (RSs) that may not be sufficient to degrade specific types of OMPs. Furthermore, the concentrations and types of RSs are highly influenced by anions and dissolved organic matter (DOM) coexisting in real waters, making systematic understandings of their interfering mechanisms difficult. To identify and address the knowledge gaps, this review provides a comparison of the generations and variations of various types of RSs in different UV-ATPs. These analyses not only prove the importance of water matrices on formation and consumption of primary and secondary RSs under different conditions, but also highlight the non-negligible roles of optical properties and reactivities of DOM and anions. For example, different UV-ATPs may be applicable to different target OMPs under different conditions; and the concentrations and roles of secondary RSs may outperform those of primary RSs in OMP degradation for real applications. With continuous progress and outstanding achievements in the UV-ATPs, it is hoped that the findings and conclusions of this review could facilitate further research and application of UV-ATPs. [Display omitted] [ABSTRACT FROM AUTHOR]

Kinetic degradation of five typical pollutants including clothianidin (CLO), levofloxacin (LEV), p-nitrosodimethylaniline (RNO), paracetamol (PCM), and basic fuchsin (BF) by UV/persulfate (UV/PS) and other advanced oxidation processes (AOPs) (i.e., UV/H 2 O 2 , Fe2+/H 2 O 2 , electrochemical process, UV/PS/heat, UV/PS/Fe2+, UV/PS/Fe 2 O 3 , and UV/PS/rGO) were studied. The result showed that all pollutants were effectively degraded by UV/PS with different degradation rates. The oxidizing factors contributing to the pollutant degradation in UV/PS were studied, showing that UV is the predominant contributor to CLO degradation, while its contribution is negligible in the degradation of other compounds. •OH and SO 4 •- were the main radicals contributing to the degradation of all pollutants in UV/PS, except CLO. The second-order rate constant of •OH and SO 4 •- towards pollutants was determined according to the competition kinetic model, to be in the range of 109-1010 M−1 s−1. The degradation rate of pollutants in different AOPs were varied, because the oxidizing factors and their role in AOP systems directly affect the degradation efficiency of pollutants. In all AOPs, •OH radical played a major role in their degradation. The presence of water matrices has different influences on the degradation rates of pollutants. For example, 10 mM NO 2 - inhibited the degradation of pollutants to 99.1%, whereas Br-, SO 4 2-, and F- had a lower inhibitory effect on their degradation. HPO 4 2- can improve the degradation rate of BF, but it also significantly inhibited the degradation of PCM. The results also revealed that UV/PS/Fe2+ and UV/PS/rGO can remarkably increase the degradation efficiency of all pollutants, while using α-Fe 2 O 3 and heat were less efficient. In addition, other parameters including COD removal, energy consumption, and toxicity assessment were also investigated to evaluate the potential application of UV/PS in practice. [Display omitted] • Kinetic degradation of five typical pollutants was investigated in UV/PS. • •OH radical contributed in the degradation of pollutants in AOPs. • Pollutants were degraded differently in each AOP. • Br-, SO 4 2-, and F- slowly inhibitedthe degradation of pollutants; NO 2 - reduced their degradation up to 99.1%. • UV/PS/Fe2+ and UV/PS/rGO remarkably increased the degradation efficiency of all pollutants. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • HCO 3 −/CO 3 2− in simulated seawater weaken NO x removal performance by UV/electrolyzed seawater. • NO x removal efficiency with multi-variables was optimized through a Box-Behnken design method. • The OH radical greatly contributed to NO x removal by UV/chlorine in seawater environment. • Reaction pathways of NO x removal by UV/electrolyzed seawater were proved to be pH-dependent. Abstract UV/chlorine has attracted much attention in flue gas and water treatment fields in recent years. However, only a few studies highlighted gas pollutants removal performance of UV/chlorine method in real water. In this study, nitrogen oxide (NO x) removal using UV-irradiated electrolyzed seawater (UV/electrolyzed seawater) was explored under simulated seawater environment in a semi-batch photochemical reactor. Comparison experiments between UV/H 2 O 2 and UV/chlorine in both freshwater and seawater systems were performed. Results showed that NO removal efficiency in UV/chlorine freshwater system was higher than those in UV/chlorine seawater system, due to radical scavenging effects of water matrices in seawater. Several strong reactive radicals (e.g., OH, Cl, OCl, ClOH −) yielded from UV/chlorine system were considered to contribute to NO x removal, among which the role of OH radical was confirmed by radical-trapping experiments. The alkalinity of the seawater adversely impacted contributions of these reactive radicals to NO x removal, which caused a sharp drop in NO x removal efficiencies. Comparatively, the chloride ion in seawater had slight influences on NO x removal efficiencies of UV/electrolyzed seawater. Then, optimization of NO x removal efficiencies against three key variables (active chlorine concentration, UV irradiation dose, and initial pH) was investigated in simulated seawater using Design Expert Software. A regression model of NO x removal efficiency was obtained with satisfactory accuracy. Results indicated that active chlorine concentration and UV irradiation dose significantly influenced NO x removal efficiencies, compared with pH effects. Furthermore, NO x removal mechanisms involved in reactive radicals were discussed for UV/electrolyzed seawater method. Due to pH-dependent characteristics of both active chlorine species and carbonate species in electrolyzed seawater, NO x removal pathways by UV/electrolyzed seawater were different as the environment changed from acid to alkalinity. [ABSTRACT FROM AUTHOR]

BACKGROUND: Nowadays, due to the inappropriate use of antibiotics, significant quantities have been detected in environmental samples. Therefore there is a need for a technology to eliminate the accumulation of pharmaceuticals in receiving water bodies. In recent years electrochemical oxidation showed superior efficiency for the purification of water from pharmaceuticals. RESULTS: boron doped diamond (BDD) showed better efficiency than platinum electrode and stainless steel for the degradation of 500 µg L−1 tetracycline (TC) with 0.1 mol L−1·Na2SO4. The presence of 200 mg L−1 bicarbonates decreased the apparent kinetic constant from 0.328 to 0212 min−1. Instead, the addition of 200 mg L−1 NaCl increased the kinetic constant by almost four times, while the presence of 10 mg L−1 of humic acid decreased the kinetic constant by 18%. The process was favored in real environmental matrices like bottled water and wastewater in comparison with ultrapure water. The use of BDD as both anode and cathode enhanced the efficiency by almost 20%. The presence of UVA or solar radiation increased the decomposition of tetracycline by 14%. Changes in toxicity to Vibrio fisheri bacteria during treatment of TC in the secondary effluent are mainly attributed to the formation of intermediates of the water matrix itself and does not follow the TC removal. CONCLUSIONS: Electrochemical oxidation was favored for removal of TC in real water matrices due to the presence of chlorides. The use of BDD as both anode and cathode with simultaneous solar irradiation is a promising technology for water remediation from TC. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this study, the detection and quantification of multiple classes of antibiotics in water matrices are proposed using a lab-made solid phase microextraction (SPME) fiber coupled with high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). The lab-made fiber was prepared using a graphene oxide (G), carbon nanotubes (C), and tin dioxide (T) composite, namely GCT, with polyacrylonitrile (PAN) as supporting material. The detected antibiotics were enrofloxacin, sulfathiazole, erythromycin, and trimethoprim. The custom-made fiber was found to be superior compared with a commercial C18 fiber. The excellent reproducibility and lower intra-fiber relative standard deviations (RSDs 1.8% to 6.8%) and inter-fiber RSDs (4.5% to 8.8%) made it an ideal candidate for the detection of traces of antibiotics in real environmental samples. The proposed validated method provides a satisfactory limit of detection and good linear ranges with higher (>0.99) coefficient of determination in the aqueous system. Application of the method was made in different real water systems such as river, pond and tap water using the standard spiking method. Excellent sensitivity, reproducibility, lower amount of sample detection and higher recovery was found in a real water sample. Therefore, the extraction method was successfully applied to the detection and quantification of multiple classes of antibiotics in different aqueous systems with satisfactory results.

A supramolecular solvent-based microextraction procedure for preconcentration of four most common sugarcane herbicides (diuron, hexazinone, ametryn and tebuthiuron) from groundwater and surface water samples with further determination by High Performance Liquid Chromatography with Photodiode Array detector (HPLC-DAD) is proposed. The proposed method involves the use of a supramolecular solvent in which reverse micelles of 1-decanol are dispersed in tetrahydrofuran/water. The extraction of four herbicides performed at pH 4.0 requires low sample volume (10.0 mL), low extraction time (30 s of extraction and 10 min of centrifugation), low amount of organic solvents (50 μL of 1-decanol and 100 μL of THF) and provides high preconcentration factors (48.5 to diuron, 15.1 to hexazinone, 47.4 to ametryn and 21.0 to tebuthiuron). The limits of detection (LOD), quantification (LOQ), the precision (RSD) and the accuracy (RE) of the developed method ranged between 0.13 and 1.45 μg L − 1 , 0.43–4.85 μg L − 1 , 2.4–6.8% and 0.6–6.2%, respectively. Recovery values obtained by applying the proposed method in spiked groundwater and surface water samples at μg L − 1 levels varied in the range of 95–111%. The quantification of some analyzed herbicides in natural waters showed clearly the importance of investigates herbicides concentrations in regions of sugarcane cultivation predominance. [ABSTRACT FROM AUTHOR]

Water bodies are being polluted rapidly by disposal of toxic chemicals with their huge entrance into drinking water supply chain. Among these pollutants, heavy metal ions (HMIs) are the most challenging one due to their non-biodegradability, toxicity, and ability to biologically hoard in ecological systems, thus posing a foremost danger to human health. This can be addressed by robust, sensitive, selective, and reliable sensing of metal ions which can be achieved by Metal organic frameworks (MOF) based electrochemical sensors. In the present era, MOFs have caught greater interest in a variety of applications including sensing of hazardous pollutants such as heavy metal ions. So, in this review article, types, synthesis and working mechanism of MOF based sensors is explained to give general overview with updated literature. First time, detailed study is done for sensing of metal ions such as chromium, mercury, zinc, copper, manganese, palladium, lead, iron, cadmium and lanthanide by MOFs based electrochemical sensors. The use of MOFs as electrochemical sensors has attractive success story along with some challenges of the area. Considering these challenges, we attempted to highlight the milestone achieved and shortcomings along with future prospective of the MOFs for employing it in electrochemical sensing devices for HMIs. Finally, challenges and future prospects have been discussed to promote the development of MOFs-based sensors in future. [Display omitted] • MOF as electrochemical sensing systems. • Various synthetic approaches for synthesizing MOFs sensing materials. • Landscape view for the sensing of different heavy metals. • Challenges and detection mechanism of MOFs based sensors. [ABSTRACT FROM AUTHOR]

The presence of per- and poly-fluoroalkyl substances (PFASs) in water is of global concern due to their high stability and toxicity even at very low concentrations. There are several technologies for the remediation of PFASs, but most of them are inadequate either due to limited effectiveness, high cost, or production of a large amount of sludge. Electrochemical oxidation (EO) technology shows great potential for large-scale application in the degradation of PFASs due to its simple procedure, low loading of chemicals, and least amount of waste. Here, we have reviewed the recent progress in EO methods for PFAS degradation, focusing on the last 10 years, to explore an efficient, cost-effective, and environmentally benign remediation technology. The effects of important parameters (e.g., anode material, current density, solution pH, electrolyte, plate distance, and electrical connector type) are summarized and evaluated. Also, the energy consumption, the consequence of different PFASs functional groups, and water matrices are discussed to provide an insight that is pivotal for developing new EO materials and technologies. The proposed degradation pathways of shorter-chain PFAS by-products during EO of PFAS are also discussed., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Prof. Naresh Kumar reports financial support was provided by Australian Research Council. Prof. Naresh Kumar reports a relationship with University of New South Wales that includes: employment., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Simple semi-theoretical models were developed to estimate the performance of three different kinds of advanced oxidation processes (AOPs) in the degradation of pharmaceuticals. The AOPs included the photo-Fenton process as an example of a liquid-liquid reaction, the TiO 2 photocatalytic oxidation process as a solid-liquid reaction, and the combined ozone and hydrogen peroxide oxidation process as a gas-liquid reaction; the effects of the aqueous matrices (CESs: co-existing substances) of actual wastewater on the removal of pharmaceuticals (carbamazepine and diclofenac) was taken into account. By comparing the characteristic parameters of the models, obtained from the experiments using pure water and actual wastewater, the effects of CESs on the respective removal mechanisms could be separately and quantitatively evaluated. As a general tendency, the AOPs proceeded less effectively (were inhibited) in the matrices containing CESs, as observed with the use of a lower initial concentration of pharmaceuticals. The inhibition mechanisms differed for the three types of AOPs. In the photo-Fenton process, the Fenton reaction was improved by the incorporation of CESs, while the photo-reduction reaction was significantly inhibited. In the TiO 2 photocatalytic oxidation process, competition between the pharmaceuticals and CESs for adsorption on the catalyst surface was a less significant inhibitory factor than the scavenger effects of the CESs. The combined ozone and hydrogen peroxide oxidation process was most strongly inhibited by CESs among the AOPs investigated in this study. [ABSTRACT FROM AUTHOR]

In this study, the enhancement for trace analysis of sulfonamide antibiotics (sulfathiazole, sulfamethoxazole and sulfadimethoxine) and trimethoprim in water matrices is proposed using bar adsorptive microextraction combined with micro-liquid desorption followed by high-performance liquid chromatography with diode array detection (BAμE-μLD/HPLC-DAD). By comparing different polymers and activated carbons as sorbent coatings for BAμE, the polystyrene-divinylbenzene polymer (PS-DVB) showed the best selectivity for the compounds under study. Assays performed through BAμE(PS-DVB)-μLD on 25 mL of ultrapure water samples spiked at the 8.0 μg L −1 level showed recoveries ranging from 63.8 ± 1.5% to 84.2 ± 1.9%, under optimized experimental conditions. The validated method provided satisfactory limits of detection (0.08–0.16 μg L −1 ) and good linear dynamic ranges (0.16–8.00 μg L −1 ) with determination coefficients higher than 0.9958. The proposed analytical methodology was applied to real matrices, such as tap, estuarine and wastewater samples using the standard addition method. It showed to be easy to implement, with good reproducibility, sensitivity and requiring small amount of sample. Furthermore, negligible consumption of organic solvents was used in compliance with the green analytical chemistry principles. When compared to other well-established microextraction approaches, BAμE demonstrated better performance concerning recovery yields and sensitivity. [ABSTRACT FROM AUTHOR]

Norfloxacin (NF) is an effective antimicrobial drug that poses a threat to human health because of its environmental residues. In this research, ZnO nanoflowers and triangular silver nanoplates (T-Ag) were synthesized using a facile sol–gel method. The synergistic photocatalytic effects of the adding different triangular silver nanoplates concentration over ZnO nanoflowers on the NF removal under visible light was studied for the first time. Photodegradation results demonstrated that T-Ag could significantly enhance the activity of ZnO nanoflowers. The degradation efficiency of NF by T-Ag/ZnO nanoflowers was affected in the different water matrices, including ultra-pure, tap, and river water. The effects of the dosage of ZnO nanoflowers, initial NF concentration, and pH on the photocatalytic activity of ZnO nanoflowers were also explored. The results show that the highest rate constant for the degradation of NF is obtained with 1 mg L −1 of T-Ag, 0.1 g L −1 of ZnO, initial NF concentration of 10 mg L −1 , and pH of 11 in ultra-pure water. The possible mechanism of the photocatalytic degradation of NF using T-Ag/ZnO nanoflowers through the addition of scavenger agents (i.e., EDTA and methanol) was also studied. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are a group of organic compounds that have a molecular structure containing carbon and their chemical properties allow them to be easily converted to steam and gas and remain for a long period of time and have diverse effects on the environment. The purpose of this study is determination of the concentration of VOCs such as alachlor, anthracene, benzene, bromoform, chloroform, heptachlor, isophorone, tetrachloroethylene, γ -chlordane, toluene, etc. in water matrices. The results showed that among studies conducted on VOCs, the concentration of tetrachloroethylene, m,p-xylene, and toluene were at the top in water matrices, and the lowest average concentrations were found in chloroform, anthracene, and butyl benzyl phthalate. In terms of VOC concentrations in water matrices, China was the most polluted country. Moreover, the data analysis indicated that China was the only country with carcinogenic risk. A Monte-Carlo simulation showed that although the averages obtained were comparable to the acceptable limits, for heptachlor, the maximum carcinogenic risk is achieved at a level that is slightly over the limit, only 25% from the population being exposed. [Display omitted] • Tetrachloroethylene, m,p-Xylene, and Toluene in water were higher than other VOCs. • China showed a higher risk associated with VOCs in water matrices. • Monte-Carlo simulation indicated 25% of the population of China being exposed. • Membrane techniques were main technique of VOCs separation from water matrices. [ABSTRACT FROM AUTHOR]

Hepatitis A is a common form of viral hepatitis. It is usually transmitted through the ingestion of contaminated food and water. This systematic review was carried out to summarise the overall prevalence of Hepatitis A virus (HAV) in different water matrices: untreated and treated wastewater, surface water, groundwater, drinking water, and others (e.g., irrigation water and floodwater). The literature search was performed in four databases: PubMed, Web of Science, Global Index Medicus, and Excerpta Medica Database. Heterogeneity (I2) was assessed using the χ2 test on the Cochran Q statistic and H parameters. A total of 200 prevalence data from 144 articles were included in this meta-analysis. The overall prevalence of HAV in water matrices was 16.7% (95% CI: 13.4−20.3). The prevalence for individual matrix was as follows: 31.4% (95% CI: 23.0−40.4) untreated wastewater, 18.0% (95% CI: 9.5−28.2) treated wastewater, 15.0% (95% CI: 10.1−20.5) surface water, 2.3% (95% CI: 0.1−6.0) in groundwater, 0.3% (95% CI: 0.0−1.7) in drinking water, and 8.5% (95% CI: 3.1−15.6) in other matrices. The prevalence was higher in low-income economies (29.0%). Africa and Eastern Mediterranean were the regions with higher HAV prevalence values. This study showed a high heterogeneity (I2 > 75%) with a significant publication bias (p value Egger test < 0.001). The results of this review suggest that water matrices could be an important route of HAV transmission even in industrialized countries, despite the lower prevalence compared to less industrialized countries, and the availability of advanced water management systems. More effective water/wastewater treatment strategies are needed in developing countries to limit the environmental circulation of HAV.

Transition metal-exchanged dealuminated Y zeolites were used to adsorb atrazine from aqueous solutions, followed by regeneration of the sorbents and destruction of the sorbed atrazine with microwave irradiation. Exchange of copper and iron into the zeolite's micropores significantly enhanced its sorption capacity and selectivity toward atrazine, and increased the microwave-induced degradation rate of the sorbed atrazine by 3–4-folds. Both the copper- and iron-exchanged zeolites could be regenerated and reused multiple times, while the catalytic activity of the latter was more robust due to the much greater chemical stability of Fe 3+ species in the micropores. The presence of humic acid, and common cations and anions had little impact on the sorption of atrazine on the transition metal-exchanged zeolites. In the treatment of atrazine spiked in natural surface water and groundwater samples, sorptive removal of atrazine was found to be impacted by the level of dissolved organic carbon, probably through competition for the micropore spaces and pore blocking, while the water matrices exhibited no strong effect on the microwave-induced degradation of sorbed atrazine. Overall, iron-exchanged dealuminated Y zeolites show great potential for removal and destruction of atrazine from contaminated surface water and groundwater in practical implementation of the novel treatment technology. [ABSTRACT FROM AUTHOR]

In the present work, the development of a novel analytical approach which combines a miniaturized bar adsorptive microextraction device with a micro-liquid desorption in one single step, followed by high performance liquid chromatography with diode array detection (BAµE-µLD/HPLC–DAD), is proposed for the determination of trace levels of nine steroid hormones (estriol, 17ß-estradiol, 17α-estradiol, 19-northisterone, 17α-ethynylestradiol, estrone, d -(-)-norgestrel, progesterone and mestranol) in environmental and biological matrices. From the comparison of ten different coating phases (five polymeric and five activated carbon sorbents), the modified pyrrolidone polymer (P2) showed the best compromise between selectivity and efficiency. Assays performed through BAµE(P2, 1.3 mg)-µLD(100 µL)/HPLC–DAD on 25 mL of ultrapure water samples spiked at the 6.0 μg/L level, yielded recoveries ranging from 93±9% to 101±8%, under optimized experimental conditions. The analytical performance showed convenient detection (50.0–100.0 ng/L) and quantification limits (165.0–330.0 ng/L), as well as good linear dynamic ranges (0.2–24.0 µg/L) with remarkable determination coefficients ( r 2 >0.9968). Excellent repeatability were also achieved through intraday (RSD<14%) and interday (RSD<12%) experiments. The application of the proposed analytical approach on environmental water and urine samples, using the standard addition methodology (SAM), revealed good linearity and sensitivity at trace level, with the detection of some of the target compounds. In short, the miniaturization of the analytical device for microextraction combined with the minimization of the solvent volume for back-extraction in one single step demonstrated remarkable performance, increasing the enrichment factor, being simultaneously more easier to implement and environment friendly. [ABSTRACT FROM AUTHOR]