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The overall aim of this work was to examine the degradation of trimethoprim (TMP), which is an antibacterial agent, during the application of two advanced oxidation process (AOP) systems in secondary treated domestic effluents. The homogeneous solar Fenton process (hv/Fe2+/H2O2) and heterogeneous photocatalysis with titanium dioxide (TiO2) suspensions were tested. It was found that the degradation of TMP depends on several parameters such as the amount of iron salt and H2O2, concentration of TiO2, pH of solution, solar irradiation, temperature and initial substrate concentration. The optimum dosages of Fe2+ and H2O2 for homogeneous ([Fe2+] =5 mg L-1, [H2O2] = 3.062 mmol L-1) and TiO2 ([TiO2] = 3 g L-1) for heterogeneous photocatalysis were established. The study indicated that the degradation of TMP during the solar Fenton process is described by a pseudo-first-order reaction and the substrate degradation during the heterogeneous photocatalysis by the Langmuir-Hinshelwood kinetics. The toxicity of the treated samples was evaluated using a Daphnia magna bioassay and was finally decreased by both processes. The results indicated that solar Fenton is more effective than the solar TiO2 process, yielding complete degradation of the examined substrate within 30 min of illumination and dissolved organic carbon (DOC) reduction of about 44% whereas the respective values for the TiO2 process were ∼70% degradation of TMP within 120 min of treatment and 13% DOC removal. [ABSTRACT FROM AUTHOR]

In this work, a sensitive and highly selective method was developed and validated to study the degradation of two antibiotic compounds (ofloxacin (OFX) and trimethoprim (TMP)), spiked in secondary treated domestic effluents, by the solar Fenton process. Three different chromatographic columns were tested on a ultra performance liquid chromatography-tandem mass spectrometric (UPLC-MS/MS) instrument working in the electrospray ionization (ESI) mode with twelve combinations of eluting solvents. Samples were enriched prior to the analysis by solid phase extraction using the hydrophilic-lipophilic balanced (HLB) reversed phase polymeric sorbent. The method was optimized and showed very good performance characteristics and was successfully applied to study the degradation kinetics of the selected antibiotics during the solar Fenton process applied. The degradation was found to follow a pseudo first-order kinetics for both compounds at initial concentration of 100 μg L-1 with k=0.0345 min-1 for OFX and k=0.0768 min-1 for TMP, whereas the complete removal was achieved after 120 mm of treatment for both compounds. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the efficiency of solar and UV-A photocatalysis with suspended TiO2 to degrade ibuprofen and carbamazepine in aqueous matrices. Emphasis was given on the effect of various operating conditions such as catalyst type (six commercially available titanium oxide samples were tested) and concentration (50-3000 mg/L), initial drug concentration (5-20 mg/L), solution pH (3-10), the addition of hydrogen peroxide (0.07-1.4 mM), and the matrix (pure water and treated domestic wastewater) on degradation and mineralization. The former was assessed monitoring sample absorbance at each drug's characteristic wavelength, while the latter measuring dissolved organic carbon. The best performance was achieved at lower drug concentrations irradiated by UV-A in the presence of Degussa P25 catalyst and hydrogen peroxide in pure water. [ABSTRACT FROM AUTHOR]

The use of low frequency (20 kHz), high energy ultrasound for the degradation of the antibiotic ofloxacin in water was investigated. Experiments were performed with a horn-type ultrasound generator at varying applied power densities (130-640 W/L), drug concentrations (5-20 mg/L), hydrogen peroxide concentrations (0-100mM) and sparging gases (air, oxygen, nitrogen and argon). In general, conversion (which was assessed following sample absorbance at 288 nm) increased with increasing ultrasound energy and peroxide concentration and decreasing initial drug concentration. Moreover, reactions under an argon atmosphere were faster than with diatomic gases, possibly due to argon's physical properties (e.g. solubility, thermal conductivity and specific heat ratio) favoring sonochemical activity. Overall, low to moderate levels of ofloxacin degradation were achieved (i.e. it never exceeded 50%), thus indicating that radical reactions in the liquid bulk rather than thermal reactions in the vicinity of the cavitation bubble are responsible for ofloxacin degradation. [ABSTRACT FROM AUTHOR]

Abstract: The photocatalytic conversion of two β-blockers, namely atenolol and propranolol in aqueous TiO2 suspensions was investigated. Irradiation was provided by a solar simulator equipped with 1kW Xe-OP lamp, while emphasis was given on the effect of catalyst type and loading (50–3000mg/L), substrate concentration (5–30mg/L), initial solution pH (3–10), and the addition of H2O2 (0.07–1.4mM) and oxygen on degradation in two matrices (i.e. pure water and treated municipal effluent). Of the various catalysts tested, Degussa P25 was highly active yielding up to about 80% conversion after 120min of reaction. In general, conversion was favored at lower substrate concentrations, near-neutral pH values and in the absence of other organics (i.e. in pure water), while the addition of H2O2 did not accelerate kinetics which seem to follow the Langmuir–Hinshelwood model. Toxicity to D. magna was evaluated prior to and after photocatalytic treatment. Toxicity increased during the early stages of the reaction and then progressively decreased upon the elimination of the substrate and its reaction intermediates, with propranolol being more toxic than atenolol. [Copyright &y& Elsevier]

Abstract: Two different technical approaches based on advanced oxidation processes (AOPs), solar Fenton homogeneous photocatalysis (hv/Fe2+/H2O2) and heterogeneous photocatalysis with titanium dioxide (TiO2) suspensions were studied for the chemical degradation of the fluoroquinolone ofloxacin in secondary treated effluents. A bench-scale solar simulator in combination with an appropriate photochemical batch reactor was used to evaluate and select the optimal oxidation conditions of ofloxacin spiked in secondary treated domestic effluents. The concentration profile of the examined substrate during degradation was determined by UV/Vis spectrophotometry. Mineralization was monitored by measuring the dissolved organic carbon (DOC). The concentrations of Fe2+ and H2O2 were the key factors for the solar Fenton process, while the most important parameter of the heterogeneous photocatalysis was proved to be the catalyst loading. Kinetic analyses indicated that the photodegradation of ofloxacin can be described by a pseudo-first-order reaction. The rate constant (k) for the solar Fenton process was determined at different Fe2+ and H2O2 concentrations whereas the Langmuir–Hinshelwood (LH) kinetic expression was used to assess the kinetics of the heterogeneous photocatalytic process. The conversion of ofloxacin depends on several parameters based on the various experimental conditions, which were investigated. A Daphnia magna bioassay was used to evaluate the potential toxicity of the parent compound and its photo-oxidation by-products in different stages of oxidation. In the present study solar Fenton has been demonstrated to be more effective than the solar TiO2 process, yielding complete degradation of the examined substrate and DOC reduction of about 50% in 30 min of the photocatalytic treatment. [ABSTRACT FROM AUTHOR]

With the global concerns on antibiotic resistance (AR) as a public health issue, it is pivotal to have data exchange platforms for studies on antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in the environment. For this purpose, the NORMAN Association is hosting the NORMAN ARB&ARG database, which was developed within the European project ANSWER. The present article provides an overview on the database functionalities, the extraction and the contribution of data to the database. In this study, AR data from three studies from China and Nepal were extracted and imported into the NORMAN ARB&ARG in addition to the existing AR data from 11 studies (mainly European studies) on the database. This feasibility study demonstrates how the scientific community can share their data on AR to generate an international evidence base to inform AR mitigation strategies. The open and FAIR data are of high potential relevance for regulatory applications, including the development of emission limit values / environmental quality standards in relation to AR. The growth in sharing of data and analytical methods will foster collaboration on risk management of AR worldwide, and facilitate the harmonization in the effort for identification and surveillance of critical hotspots of AR. The NORMAN ARB&ARG database is publicly available at: https://www.norman-network.com/nds/bacteria/., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The complexity around the dynamic markets for new psychoactive substances (NPS) forces researchers to develop and apply innovative analytical strategies to detect and identify them in influent urban wastewater. In this work a comprehensive suspect screening workflow following liquid chromatography - high resolution mass spectrometry analysis was established utilising the open-source InSpectra data processing platform and the HighResNPS library. In total, 278 urban influent wastewater samples from 47 sites in 16 countries were collected to investigate the presence of NPS and other drugs of abuse. A total of 50 compounds were detected in samples from at least one site. Most compounds found were prescription drugs such as gabapentin (detection frequency 79%), codeine (40%) and pregabalin (15%). However, cocaine was the most found illicit drug (83%), in all countries where samples were collected apart from the Republic of Korea and China. Eight NPS were also identified with this protocol: 3-methylmethcathinone 11%), eutylone (6%), etizolam (2%), 3-chloromethcathinone (4%), mitragynine (6%), phenibut (2%), 25I-NBOH (2%) and trimethoxyamphetamine (2%). The latter three have not previously been reported in municipal wastewater samples. The workflow employed allowed the prioritisation of features to be further investigated, reducing processing time and gaining in confidence in their identification., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The occurrence of contaminants of emerging concern (CECs) or heavy metals in reclaimed water used for agricultural irrigation may affect crop morphology and physiology. Here, we analyzed lettuce (Lactuca sativa) grown in outdoor lysimeters and irrigated with either tap water, used as a control, or reclaimed water: CAS-reclaimed water, an effluent from a conventional activated sludge system (CAS) followed by chlorination and sand filtration, or MBR-reclaimed water, an effluent from a membrane biological reactor (MBR). Chemical analyses identified seven CECs in the reclaimed waters, but only two of them were detected in lettuce (carbamazepine and azithromycin). Metabolomic and transcriptomic analyses revealed that irrigation with reclaimed water increased the concentrations of several crop metabolites (5-oxoproline, leucine, isoleucine, and fumarate) and of transcripts codifying for the plant stress-related genes Heat-Shock Protein 70 (HSP70) and Manganese Superoxide Dismutase (MnSOD). In both cases, MBR-water elicited the strongest response in lettuce, perhaps related to its comparatively high sodium adsorption ratio (4.5), rather than to its content in CECs or heavy metals. Our study indicates that crop metabolomic and transcriptomic profiles depend on the composition of irrigating water and that they could be used for testing the impact of water quality in agriculture., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Antibiotics have revolutionised medicine in the last century and enabled the prevention of bacterial infections that were previously deemed untreatable. However, in parallel, bacteria have increasingly developed resistance to antibiotics through various mechanisms. When resistant bacteria find their way into terrestrial and aquatic environments, animal and human exposures increase, e.g., via polluted soil, food, and water, and health risks multiply. Understanding the fate and transport of antibiotic resistant bacteria (ARB) and the transfer mechanisms of antibiotic resistance genes (ARGs) in aquatic environments is critical for evaluating and mitigating the risks of resistant-induced infections. The conceptual understanding of sources and pathways of antibiotics, ARB, and ARGs from society to the water environments is essential for setting the scene and developing an appropriate framework for modelling. Various factors and processes associated with hydrology, ecology, and climate change can significantly affect the fate and transport of ARB and ARGs in natural environments. This article reviews current knowledge, research gaps, and priorities for developing water quality models to assess the fate and transport of ARB and ARGs. The paper also provides inputs on future research needs, especially the need for new predictive models to guide risk assessment on AR transmission and spread in aquatic environments., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Scarcity of freshwater for agriculture has led to increased utilization of treated wastewater (TWW), establishing it as a significant and reliable source of irrigation water. However, years of research indicate that if not managed adequately, TWW may deleteriously affect soil functioning and plant productivity, and pose a hazard to human and environmental health. This review leverages the experience of researchers, stakeholders, and policymakers from Israel, the United-States, and Europe to present a holistic, multidisciplinary perspective on maximizing the benefits from municipal TWW use for irrigation. We specifically draw on the extensive knowledge gained in Israel, a world leader in agricultural TWW implementation. The first two sections of the work set the foundation for understanding current challenges involved with the use of TWW, detailing known and emerging agronomic and environmental issues (such as salinity and phytotoxicity) and public health risks (such as contaminants of emerging concern and pathogens). The work then presents solutions to address these challenges, including technological and agronomic management-based solutions as well as source control policies. The concluding section presents suggestions for the path forward, emphasizing the importance of improving links between research and policy, and better outreach to the public and agricultural practitioners. We use this platform as a call for action, to form a global harmonized data system that will centralize scientific findings on agronomic, environmental and public health effects of TWW irrigation. Insights from such global collaboration will help to mitigate risks, and facilitate more sustainable use of TWW for food production in the future., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Hila Korach-Rechtman reports a relationship with Kando Environmental Services LTD that includes: employment., (© 2023 The Author(s).)

To address water shortage challenges, treated wastewater is used to meet the demand for irrigation water in several countries worldwide. Considering the presence of pollutants in treated wastewater, its use for land irrigation might have an impact in the environment. This review article focuses on the combined effects (or potential joint toxicity) of microplastics (MPs)/nanoplastics (NPs) and other environmental contaminants present in treated wastewater on edible plants after irrigation. Initially, the concentrations of MPs/NPs in wastewater treatment plant effluents and surface waters are summarized, indicating the presence of MPs/NPs in both water matrices (i.e., wastewater after receiving treatment and lakes/rivers). Then, the results of 19 studies related to joint toxicity of MPs/NPs and co-contaminants (e.g., heavy metals and pharmaceuticals) on edible plants, are reviewed and discussed. This concurrent presence may result in several combined effects on edible plants, e.g., rapid root growth, increase in antioxidant enzymes, decrease in photosynthetic rate and increased production of ROS. These effects, as discussed in the various studies on which this review is based, can generate antagonistic or even neutral impact on plants, depending on the size of MPs/NPs and their mixing ratio with the co-contaminants. However, a combined exposure of edible plants to MPs/NPs and co-contaminants can also lead to hormetic adaptive responses. The data reviewed and discussed herein may relieve overlooked environmental impacts of treated wastewater reuse and may be useful to address challenges related to the combined effects of MPs/NPs and co-contaminants on edible plants after irrigation. The conclusions drawn in this review article are relevant to both direct (i.e., treated wastewater irrigation) and indirect (i.e., discharging treated wastewater in surface waters used for irrigation purposes) reuse, and may contribute to the implementation of the European Regulation 2020/741 on the minimum requirements for water reuse., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Surveillance of antibiotic resistance genes (ARGs) has been increasingly conducted in environmental sectors to complement the surveys in human and animal sectors under the "One-Health" framework. However, there are substantial challenges in comparing and synthesizing the results of multiple studies that employ different test methods and approaches in bioinformatic analysis. In this article, we consider the commonly used quantification units (ARG copy per cell, ARG copy per genome, ARG density, ARG copy per 16S rRNA gene, RPKM, coverage, PPM, etc.) for profiling ARGs and suggest a universal unit (ARG copy per cell) for reporting such biological measurements of samples and improving the comparability of different surveillance efforts.

The proliferation of new psychoactive substances (NPS) over recent years has made their surveillance complex. The analysis of raw municipal influent wastewater can allow a broader insight into community consumption patterns of NPS. This study examines data from an international wastewater surveillance program that collected and analysed influent wastewater samples from up to 47 sites in 16 countries between 2019 and 2022. Influent wastewater samples were collected over the New Year period and analysed using validated liquid chromatography - mass spectrometry methods. Over the three years, a total of 18 NPS were found in at least one site. Synthetic cathinones were the most found class followed by phenethylamines and designer benzodiazepines. Furthermore, two ketamine analogues, one plant based NPS (mitragynine) and methiopropamine were also quantified across the three years. This work demonstrates that NPS are used across different continents and countries with the use of some more evident in particular regions. For example, mitragynine has highest mass loads in sites in the United States, while eutylone and 3-methylmethcathinone increased considerably in New Zealand and in several European countries, respectively. Moreover, 2F-deschloroketamine, an analogue of ketamine, has emerged more recently and could be quantified in several sites, including one in China, where it is considered as one of the drugs of most concern. Finally, some NPS were detected in specific regions during the initial sampling campaigns and spread to additional sites by the third campaign. Hence, wastewater surveillance can provide an insight into temporal and spatial trends of NPS use., Competing Interests: RUH and EMD are cofounders of AquaVitas, LLC, Phoenix, Arizona, United States, an Arizona State University startup company providing commercial services in wastewater-based epidemiology. RUH also is the founder of OneWaterOneHealth, a nonprofit project of the Arizona State University Foundation., (© 2023 The Author(s).)

The occurrence of 200 multiclass contaminants of emerging concern (CECs) encompassing 168 medicinal products and transformation products (TPs), 5 artificial sweeteners, 12 industrial chemicals, and 15 other compounds was investigated in influent and effluent wastewater samples collected during 7 consecutive days from 5 wastewater treatment plants (WWTPs) located in Cyprus. The methodology included a generic solid-phase extraction protocol using mixed-bed cartridges followed by Ultra-High Performance Liquid Chromatography coupled with Quadrupole-Time of Flight Mass Spectrometry (UHPLC-QTOF-MS) analysis. A total of 63 CECs were detected at least in one sample, with 52 and 55 out of the 200 compounds detected in influents and effluents, respectively. Ten (10) out of the 24 families of parent compounds and associated TPs were found in the wastewater samples (influent or effluent). 1-H-benzotriazole, carbamazepine, citalopram, lamotrigine, sucralose, tramadol, and venlafaxine (>80 % frequency of appearance in effluents) were assessed with respect to their bioavailability in soil as part of different scenarios of irrigation with reclaimed water following a qualitative approach. A high score of 12 (high probability) was predicted for 2 scenarios, a low score of 3 (rare occasions) for 2 scenarios, while the rest 28 scenarios had scores 5-8 (unlikely or limited possibility) and 9-11 (possibly). Retrospective screening was performed with the use of a target database of 2466 compounds and led to the detection of 158 additional compounds (medicinal products (65), medicinal products TPs (15), illicit drugs (7), illicit drugs TPs (3), industrial chemicals (11), plant protection products (25), plant protection products TPs (10), and various other compounds (22). This work aspires to showcase how the presence of CECs in wastewater could be investigated and assessed at WWTP level, including an expert-based methodology for assessing the soil bioavailability of CECs, with the aim to develop sustainable practices and enhance reclaimed water reuse., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The removal of antibiotic resistance genes (ARGs) and taxon-specific markers, the bacterial community structure changes and the permanent inactivation of total bacteria including their antibiotic-resistant counterparts (ARB) in actual wastewater during a Membrane BioReactor (MBR) application followed by solar photo-Fenton oxidation at bench- and then pilot-scale under solar irradiation, were investigated. The presence of enterococci- and pseudomonad-specific taxon markers and of sul1 and ampC ARGs in the MBR effluent was confirmed, indicating the challenge of such processes, for the removal of biological molecules. On the other hand, >99 % reduction of all types of cultivable bacteria examined was observed after MBR treatment, with a 5-log reduction of E. coli and 6-log reduction of P. aeruginosa and Klebsiella spp. There was a shift in the bacterial community structure in the MBR effluent after the bench- and pilot-scale solar photo-Fenton oxidation. Notably, thermotolerant bacterial genera like Ignavibacterium and Thermomonas were prevalent during the pilot-scale process operated at a high ambient temperature, while the most prevalent genera were Mycobacterium, Nocardioides and Mesorhizobium, which are primarily not pathogenic and plant-related. In agreement, a different bacterial community structure according to the G-C content after DGGE analysis was noted between the MBR and solar photo-Fenton oxidation-treated effluents, but interestingly also between the bench- and pilot-scale oxidation-treated effluents. There was complete absence of ARGs after the bench-scale solar photo-Fenton oxidation application but not after the pilot-scale treatment (1.56 and 1.53 log 10 CE 100 ng -1 DNA, of sul and ermB, respectively). Taxon-specific markers were found in both oxidation setups. Inactivation of cultivable Escherichia coli, Pseudomonas aeruginosa and Klebsiella spp. (including ARB) was achieved during both oxidation setups, with no further re-activation observed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The aquatic environment is a hotspot for the transfer of antibiotic resistance to humans and animals. Several reviews have put together research efforts on the presence and distribution of antibiotic resistant bacteria (ARB), antibiotic resistance genes (ARGs), and antibiotic chemical residue (ACRs) in food, hospital wastewater, and even in other aquatic environments. However, these reports are largely focused on data from developed countries, while data from developing countries and especially those in Africa, are only marginally discussed. This review is the first effort that distills information on the presence and distribution of ARGs and ACRs in the African aquatic environments (2012-2021). This review provides critical information on efforts put into the study of ARB, ARGs, and ACRs in aquatic environments in Africa through the lens of the different sub-regions in the continent. The picture provided is compared with those from some other continents in the world. It turns out that the large economies in Africa (South Africa, Nigeria, Tunisia, Kenya) all have a few reports of ARB and ARGs in their aquatic environment while smaller economies in the continent could barely provide reports of these in their aquatic environment (in most cases no report was found) even though they have some reports on resistomes from clinical studies. Interestingly, the frequency of these reports of ARB and ARGs in aquatic environments in Africa suggests that the continent is ahead of the South American continent but behind Europe and Asia in relation to providing information on these contaminants. Common ARGs found in African aquatic environment encode resistance to sulfonamide, tetracycline, β-lactam, and macrolide classes of antibiotics. The efforts and studies from African scientists in eliminating ARB and ARGs from the aquatic environment in Africa are also highlighted. Overall, this document is a ready source of credible information for scientists, policy makers, governments, and regional bodies on ARB, ARGs, and ACRs in aquatic environments in Africa. Hopefully, the information provided in this review will inspire some necessary responses from all stakeholders in the water quality sector in Africa to put in more effort into providing more scientific evidence of the presence of ARB, ARGs, and ACRs in their aquatic environment and seek more efficient ways to handle them to curtail the spread of antibiotic resistance among the population in the continent. This will in turn, put the continent on the right path to meeting the United Nations Sustainable Development Goals #3 and #6, which at the moment, appears to be largely missed by most countries in the continent., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)