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Refereed/Peer-reviewed Flocs produced during drinking water treatment play a key role in particle separation and removal. Floc characteristics affect both sedimentation and filtration efficiency, however, the methods used to optimise the coagulant dose during treatment do not usually take these into account. This study investigated the feasibility of using the Flocculation Index (FI), obtained from a photometric dispersion analyser (PDA) during flocculation, as a control parameter to optimise turbidity removal. Five waters, natural and synthetic, with different turbidity levels (from 6 to ⁓120 NTU) and low DOC (i.e.

To understand the dynamics of antimicrobial resistance (AMR), in a One-Health perspective, surveillance play an important role. Monitoring systems already exist in the human health and livestock sectors, but there are no environmental monitoring programs. Therefore there is an urgent need to initiate environmental AMR monitoring programs nationally and globally, which will complement existing systems in different sectors. However, environmental programs should not only identify anthropogenic influences and levels of AMR, but they should also allow for identification of transmissions to and from human and animal populations. In the current review we therefore propose using antimicrobial resistant Escherichia coli as indicators for monitoring occurrence and levels of AMR in the environment, including wildlife.

Comamonas spp. are Gram-negative bacteria that catabolize a wide range of organic and inorganic substrates. Comamonas spp. are abundant in aquatic and soil environments, including wastewater, and can cause opportunistic infections in humans. Because of their potential in wastewater bioaugmentation and bioremediation strategies, the identification of Comamonas species harboring genes encoding carbapenemases and other clinically important antibiotic resistance genes warrant further investigation. Here, we present an analysis of 39 whole-genome sequences comprising three Comamonas species from aquatic environments in South Australia that were recovered on media supplemented with carbapenems. The analysis includes a detailed description of 33 Comamonas denitrificans isolates, some of which carried chromosomally acquired bla(GES-5), bla(OXA), and aminoglycoside resistance (aadA) genes located on putative genomic islands (GIs). All bla(GES-5)- and bla(OXA)-containing GIs appear to be unique to this Australian collection of C. denitrificans. Notably, most open reading frames (ORFs) within the GIs, including all antimicrobial resistance (AMR) genes, had adjacent attC sites, indicating that these ORFs are mobile gene cassettes. One C. denitrificans isolate carried an IncP-1 plasmid with genes involved in xenobiotic degradation and response to oxidative stress. Our assessment of the sequences highlights the very distant nature of C. denitrificans to the other Comamonas species and its apparent disposition to acquire antimicrobial resistance genes on putative genomic islands. IMPORTANCE Antimicrobial resistance (AMR) poses a global public health threat, and the increase in resistance to “last-resort drugs,” such as carbapenems, is alarming. Wastewater has been flagged as a hot spot for AMR evolution. Comamonas spp. are among the most common bacteria in wastewater and play a role in its bioaugmentation. While the ability of Comamonas species to catabolize a wide range of organic and inorganic substrates is well documented, some species are also opportunistic pathogens. However, data regarding AMR in Comamonas spp. are limited. Here, through the genomic analyses of 39 carbapenem-resistant Comamonas isolates, we make several key observations, including the identification of a subset of C. denitrificans isolates that harbored genomic islands encoding carbapenemase bla(GES-5) or extended-spectrum β-lactamase bla(OXA) alleles. Given the importance of Comamonas species in potential wastewater bioaugmentation and bioremediation strategies, as well as their status as emerging pathogens, the acquisition of critically important antibiotic resistance genes on genomic islands warrants future monitoring.

Refereed/Peer-reviewed Elizabethkingia species are ubiquitous in aquatic environments, colonize water systems in healthcare settings and are emerging opportunistic pathogens with reports surfacing in 25 countries across six continents. Elizabethkingia infections are challenging to treat, and case fatality rates are high. Chromosomal blaB, blaGOB and blaCME genes encoding carbapenemases and cephalosporinases are unique to Elizabethkingia spp. and reports of concomitant resistance to aminoglycosides, fluoroquinolones and sulfamethoxazole-trimethoprim are known. Here, we characterized whole-genome sequences of 94 Elizabethkingia isolates carrying multiple wide-spectrum metallo-β-lactamase (blaB and blaGOB) and extended-spectrum serine‑β-lactamase (blaCME) genes from Australian aquatic environments and performed comparative phylogenomic analyses against national clinical and international strains. qPCR was performed to quantify the levels of Elizabethkingia species in the source environments. Antibiotic MIC testing revealed significant resistance to carbapenems and cephalosporins but susceptibility to fluoroquinolones, tetracyclines and trimethoprim-sulfamethoxazole. Phylogenetics show that three environmental E. anophelis isolates are closely related to E. anophelis from Australian clinical isolates (∼36 SNPs), and a new species, E. umeracha sp. novel, was discovered. Genomic signatures provide insight into potentially shared origins and a capacity to transfer mobile genetic elements with both national and international isolates.

The extensive application of pesticides in agriculture raises concerns about their potential negative impact on soil microorganisms, being the key drivers of nutrient cycling. Most studies have investigated the effect of a single pesticide on a nutrient cycling in single soil type. We, for the first time, investigated the effect of 20 commercial pesticides with different mode of actions, applied at their recommended dose and five times their recommended dose, on nitrogen (N) microbial cycling in three different agricultural soils from southern Australian. Functional effects were determined by measuring soil enzymatic activities of β-1,4-N-acetyliglucosaminidase (NAG) and l-leucine aminopeptidase (LAP), potential nitrification (PN), and the abundance of functional genes involved in N cycling (amoA and nifH). Effects on nitrifiers diversity were determined with amplicon sequencing. Overall, the pesticides effect on N microbial cycling was dose-independent and soil specific. The fungicides flutriafol and azoxystrobin, the herbicide chlorsulfuron and the insecticide fipronil induced a significant reduction in PN and β-1,4-N-acetylglucosaminidase activity (P < 0.05) (NAG) in the alkaline loam soil with low organic carbon content i.e. a soil with properties which typically favors pesticide bioavailability and therefore potential toxicity. For the nitrifier community, the greatest pesticide effects were on the most dominant Nitrososphaeraceae (ammonia-oxidizing archaea; AOA) whose abundance increased significantly compared to the less dominant AOA and other nitrifiers. The inhibiting effects were more evident in the soil samples treated with fungicides. By testing multiple pesticides in a single study, our findings provide crucial information that can be used for pesticide hazard assessment. Refereed/Peer-reviewed

Ultrafiltration (UF) was assessed at chemical, microbiological, genetical and toxicological level and in terms of removing specific antibiotic-related microcontaminants from urban wastewater. The UF capacity to remove various antibiotics (clarithromycin, erythromycin, ampicillin, ofloxacin, sulfamethoxazole, trimethoprim, and tetracycline; [A0] = 100 μg L−1) was optimised with respect to the feed recirculation rate (25–50%) and feed/transmembrane pressure (1.5–3/1.5–2.4 bar, respectively). Here, we tested the UF capacity to reduce the cultivable bacteria (faecal coliforms, total heterotrophs, Enterococci, Pseudomonas aeruginosa), enteric opportunistic pathogens, including antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) load. Moreover, the toxicity towards Daphnia magna and three plant species was investigated. Upon optimisation of UF, the removal of antibiotics ranged from 19% for trimethoprim to 95% for clarithromycin. The concentration of cultivable faecal coliforms in the permeate was significantly reduced compared to the feed (P < 0.001), whereas all the bacterial species decreased by more than 3 logs. A similar pattern of reduction was observed for the ARGs (P < 0.001) and enteric opportunistic pathogens (~3–4 logs reduction). A nearly complete removal of the antibiotics was obtained by UF followed by granular activated carbon adsorption (contact time: 90 min), demonstrating the positive contribution of such combination to the abatement of chemical microcontaminants Refereed/Peer-reviewed

Insufficient dissolved organic matter removal results in higher residual organics (measured as dissolved organic carbon, DOC) in the treated water which can act as precursors for disinfection by-products (DBPs) and consequently increases the potential for health risk. This study aims to use drinking water treatment sludge (DWTS) as a coagulant-aid to improve the DOC removal efficiency. The effect of various DWTS doses (between 0.5 and 3 g/L) on the coagulation performance (by alum) to treat natural surface water that has relatively low turbidity and high DOC at optimum pH (~6) was examined using standard jar tests procedure. Although addition of DWTS at doses lower than 1.5 g/L improved the DOC removal efficiency (by 4% and 12% at DWTS dose of 0.5 and 1.0 g/L, respectively), the turbidity levels increased. In comparison to optimum dose of alum without DWTS, the addition of DWTS at 3 g/L led to reduce the alum dose to ~50% to achieve similar removal efficiency of organics (70% DOC removal). Further, addition of DWTS improved the floc’s characteristics (achieve larger flocs and rapid growth rate; measured by photometric dispersion analyser, PDA) and settling rate significantly, and the produced sludge volume decreased by ~50% compared to the figure with no DWTS addition. Trihalomethane formation potential (THMFP) was also reduced (up to ∼ 30%) when DWTS used. The results indicate that DWTS reuse as a coagulant-aid has the potential to reduce DOC and control DBPs formation when the organic loads require high coagulant dose exceeding the WTP design limits. Refereed/Peer-reviewed

Refereed/Peer-reviewed The environmental mobility of Cu and therefore its potential toxicity are closely linked to its attachment to natural organic matter (NOM). Geochemical models assume full lability of metals bound to NOM, especially under strong oxidizing conditions, which often leads to an overestimation of the lability of soil metals. Stable isotope dilution (SID) has been successfully applied to estimate the labile (isotopically exchangeable) pool of soil metals. However, its application to study the lability of NOM-Cu required development of a robust separation and detection approach so that free Cu ions can be discriminated from (the also soluble) NOM-Cu. We developed a SID protocol (with enriched ⁶⁵Cu) to quantify the labile pool of NOM-Cu using size exclusion chromatography coupled to a UV detector (for the identification of different NOM molecular weights) and ICP-MS (for ⁶⁵Cu/⁶³Cu ratio measurement). The Cu isotopic-exchange technique was first characterized and verified using standard NOM (SR-NOM) before applying the developed technique to an “organic-rich” podzol soil extract. The developed protocol indicated that, in contrast to the common knowledge, significant proportions of SR-NOM-Cu (25%) and soil organic-Cu (55%) were not labile, i.e., permanently locked into inaccessible organic structures. These findings need to be considered in defining Cu interactions with the reactive pool of NOM using geochemical models and risk evaluation protocols in which complexed Cu has always been implicitly assumed to be fully labile and exchangeable with free Cu ions.

Refereed/Peer-reviewed The spread of antimicrobial resistance (AMR) is a rapidly growing threat to humankind on both regional and global scales. As countries worldwide prepare to embrace a One Health approach to AMR management, which is one that recognizes the interconnectivity between human, animal, and environmental health, increasing attention is being paid to identifying and monitoring key contributing factors and critical control points. Presently, AMR sensing technologies have significantly progressed phenotypic antimicrobial susceptibility testing (AST) and genotypic antimicrobial resistance gene (ARG) detection in human healthcare. For effective AMR management, an evolution of innovative sensing technologies is needed for tackling the unique challenges of interconnected AMR across various and different health domains. This review comprehensively discusses the modern state-of-play for innovative commercial and emerging AMR sensing technologies, including sequencing, microfluidic, and miniaturized point-of-need platforms. With a unique view toward the future of One Health, we also provide our perspectives and outlook on the constantly changing landscape of AMR sensing technologies beyond the human health domain.

Escherichia coli ST131 is a globally dispersed extraintestinal pathogenic E. coli lineage contributing significantly to hospital and community acquired urinary tract and bloodstream infections. Here we describe a detailed phylogenetic analysis of the whole genome sequences of 284 Australian ST131 E. coli isolates from diverse sources, including clinical, food and companion animals, wildlife and the environment. Our phylogeny and the results of single nucleotide polymorphism (SNP) analysis show the typical ST131 clade distribution with clades A, B and C clearly displayed, but no niche associations were observed. Indeed, interspecies relatedness was a feature of this study. Thirty-five isolates (29 of human and six of wild bird origin) from clade A (32 fimH41, 2 fimH89, 1 fimH141) were observed to differ by an average of 76 SNPs. Forty-five isolates from clade C1 from four sources formed a cluster with an average of 46 SNPs. Within this cluster, human sourced isolates differed by approximately 37 SNPs from isolates sourced from canines, approximately 50 SNPs from isolates from wild birds, and approximately 52 SNPs from isolates from wastewater. Many ST131 carried resistance genes to multiple antibiotic classes and while 41 (14 %) contained the complete class one integron–integrase intI1, 128 (45 %) isolates harboured a truncated intI1 (462–1014 bp), highlighting the ongoing evolution of this element. The module intI1–dfrA17–aadA5–qacEΔ1–sul1–ORF–chrA–padR–IS1600–mphR–mrx–mphA, conferring resistance to trimethoprim, aminoglycosides, quaternary ammonium compounds, sulphonamides, chromate and macrolides, was the most common structure. Most (73 %) Australian ST131 isolates carry at least one extended spectrum β-lactamase gene, typically bla CTX-M-15 and bla CTX-M-27. Notably, dual parC-1aAB and gyrA-1AB fluoroquinolone resistant mutations, a unique feature of clade C ST131 isolates, were identified in some clade A isolates. The results of this study indicate that the the ST131 population in Australia carries diverse antimicrobial resistance genes and plasmid replicons and indicate cross-species movement of ST131 strains across diverse reservoirs.

Foliar absorption of zinc (Zn) is limited by several barriers, the first of which is the leaf cuticle. In this study, we investigated the absorption of Zn from Zn oxide nanoparticles (ZnO-NPs) in wheat (Triticum aestivum cv Gladius) and sunflower (Helianthus annuus cv Hyoleic 41) to determine the importance of NP surface coating for Zn absorption. Fourier transform infrared (FTIR) spectroscopy showed a higher polysaccharide content in the wheat cuticle than sunflower, indicated by a more pronounced glycosidic bond at 1020 cm , but wax and cutin content was similar. Scanning electron microscopy (SEM) revealed that trichome density was twice as high in wheat (3600 ± 900 cm ) as in sunflower (1600 cm ) and stomatal density four times higher in sunflower (6400 ± 800 cm in wheat and 22900 cm in sunflower). Suspensions of ZnO-NPs with coatings of different hydrophobicity were applied to leaves to compare Zn absorption using X-ray fluorescence microscopy (XFM) and inductively coupled plasma mass spectroscopy (ICP-MS). Absorption of Zn was similar between wheat and sunflower when Zn was applied at 1000 mg Zn L , but much less Zn was absorbed from all ZnO products than from soluble Zn fertiliser. Particle coating did not affect Zn absorption, but it may facilitate particle adhesion to leaves, providing a longer-term source of resupply of Zn ions to the leaves. Differences in leaf surface characteristics did not affect Zn absorption, indicating that the cuticle is the main pathway of absorption under these conditions. This article is protected by copyright. All rights reserved.

Wastewater monitoring as a public health tool is well-established and the SARS-CoV-2 (COVID-19) pandemic has seen its widespread uptake. Given the significant potential of wastewater monitoring as a public health surveillance and decision support tool, it is important to understand what measures are required to allow the long-term benefits of wastewater monitoring to be fully realized, including how to establish and/or maintain public support. The potential for positive SARS-CoV-2 detections to trigger enforced, community-wide public health interventions (e.g., lockdowns and other impacts on civil liberties) further emphasises the need to better understand the role of public engagement in successful wastewater-based monitoring programs. This paper systematically reviews the processes of building and maintaining the social license to operate wastewater monitoring. We specifically explore the relationship between different stakeholder communities and highlight the information and actions that are required to establish a social license to operate and then prevent its loss. The paper adds to the literature on social license to operate by extending its application to new domains and offers a dynamic model of social license to help guide the agenda for researcher and practitioner communities. Refereed/Peer-reviewed

Highlights • Identification of closely related (< 50 SNV) clinical and environmental aquatic Elizabethkingia anophelis isolates. • Identification of a provisional novel species Elizabethkingia umaracha. • Novel blaGOB and blaB carbapenemases and extended spectrum β-lactamase blaCME alleles identified in Elizabethkingia spp. • Analysis of the global phylogeny and pangenome of Elizabethkingia spp. • Identification of novel ICE elements carrying uncharacterised genetic cargo in 67 / 94 (71.3%) of the aquatic environments Elizabethkingia spp., Elizabethkingia species are ubiquitous in aquatic environments, colonize water systems in healthcare settings and are emerging opportunistic pathogens with reports surfacing in 25 countries across six continents. Elizabethkingia infections are challenging to treat, and case fatality rates are high. Chromosomal blaB, blaGOB and blaCME genes encoding carbapenemases and cephalosporinases are unique to Elizabethkingia spp. and reports of concomitant resistance to aminoglycosides, fluoroquinolones and sulfamethoxazole-trimethoprim are known. Here, we characterized whole-genome sequences of 94 Elizabethkingia isolates carrying multiple wide-spectrum metallo-β-lactamase (blaBand blaGOB) and extended-spectrum serine‑β-lactamase (blaCME) genes from Australian aquatic environments and performed comparative phylogenomic analyses against national clinical and international strains. qPCR was performed to quantify the levels of Elizabethkingia species in the source environments. Antibiotic MIC testing revealed significant resistance to carbapenems and cephalosporins but susceptibility to fluoroquinolones, tetracyclines and trimethoprim-sulfamethoxazole. Phylogenetics show that three environmental E. anophelis isolates are closely related to E. anophelis from Australian clinical isolates (∼36 SNPs), and a new species, E. umeracha sp. novel, was discovered. Genomic signatures provide insight into potentially shared origins and a capacity to transfer mobile genetic elements with both national and international isolates., Graphical abstract Image, graphical abstract

Background The risk of infectious disease transmission in public washrooms causes concern particularly in the context of the COVID-19 pandemic. This systematic review aims to assess the risk of transmission of viral or bacterial infections through inhalation, surface contact, and faecal-oral routes in public washrooms in healthcare and non-healthcare environments. Methods We systematically reviewed environmental sampling, laboratory, and epidemiological studies on viral and bacterial infection transmission in washrooms using PubMed and Scopus. The review focused on indoor, publicly accessible washrooms. Results Thirty-eight studies from 13 countries were identified, including 14 studies carried out in healthcare settings, 10 in laboratories or experimental chambers, and 14 studies in restaurants, workplaces, commercial and academic environments. Thirty-three studies involved surface sampling, 15 air sampling, 8 water sampling, and 5 studies were risk assessments or outbreak investigations. Infectious disease transmission was studied in relation with: (a) toilets with flushing mechanisms; (b) hand drying systems; and (c) water taps, sinks and drains. A wide range of enteric, skin and soil bacteria and enteric and respiratory viruses were identified in public washrooms, potentially posing a risk of infection transmission. Studies on COVID-19 transmission only examined washroom contamination in healthcare settings. Conclusion Open-lid toilet flushing, ineffective handwashing or hand drying, substandard or infrequent surface cleaning, blocked drains, and uncovered rubbish bins can result in widespread bacterial and/or viral contamination in washrooms. However, only a few cases of infectious diseases mostly related to faecal-oral transmission originating from washrooms in restaurants were reported. Although there is a risk of microbial aerosolisation from toilet flushing and the use of hand drying systems, we found no evidence of airborne transmission of enteric or respiratory pathogens, including COVID-19, in public washrooms. Appropriate hand hygiene, surface cleaning and disinfection, and washroom maintenance and ventilation are likely to minimise the risk of infectious disease transmission., Graphical abstract Unlabelled Image

The need for appropriate science and regulation to underpin nanosafety is greater than ever as ongoing advances in nanotechnology are rapidly translated into new industrial applications and nano-enabled commercial products. Nevertheless, a disconnect persists between those examining risks to human and environmental health from nanomaterials. This disconnect is not atypical in research and risk assessment and has been perpetuated in the case of engineered nanomaterials by the relatively limited overlap in human and environmental exposure pathways. The advent of agri-nanotechnologies brings both increased need and opportunity to change this status quo as it introduces significant issues of intersectionality that cannot adequately be addressed by current discipline-specific approaches alone. Here, focusing on the specific case of nanoparticles, we propose that a transdisciplinary approach, underpinned by the One Health concept, is needed to support the sustainable development of these technologies. The development of nano-enabled agriculture will require proper safety regulations. This Perspective outlines the need for a combined approach to regulate health and environmental risks under the same framework.

Wastewater surveillance for pathogens using reverse transcription-polymerase chain reaction (RT-PCR) is an effective and resource-efficient tool for gathering community-level public health information, including the incidence of coronavirus disease-19 (COVID-19). Surveillance of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) in wastewater can potentially provide an early warning signal of COVID-19 infections in a community. The capacity of the world's environmental microbiology and virology laboratories for SARS-CoV-2 RNA characterization in wastewater is increasing rapidly. However, there are no standardized protocols or harmonized quality assurance and quality control (QA/QC) procedures for SARS-CoV-2 wastewater surveillance. This paper is a technical review of factors that can cause false-positive and false-negative errors in the surveillance of SARS-CoV-2 RNA in wastewater, culminating in recommended strategies that can be implemented to identify and mitigate some of these errors. Recommendations include stringent QA/QC measures, representative sampling approaches, effective virus concentration and efficient RNA extraction, PCR inhibition assessment, inclusion of sample processing controls, and considerations for RT-PCR assay selection and data interpretation. Clear data interpretation guidelines (e.g., determination of positive and negative samples) are critical, particularly when the incidence of SARS-CoV-2 in wastewater is low. Corrective and confirmatory actions must be in place for inconclusive results or results diverging from current trends (e.g., initial onset or reemergence of COVID-19 in a community). It is also prudent to perform interlaboratory comparisons to ensure results' reliability and interpretability for prospective and retrospective analyses. The strategies that are recommended in this review aim to improve SARS-CoV-2 characterization and detection for wastewater surveillance applications. A silver lining of the COVID-19 pandemic is that the efficacy of wastewater surveillance continues to be demonstrated during this global crisis. In the future, wastewater should also play an important role in the surveillance of a range of other communicable diseases.

Antimicrobial resistance (AMR) is a growing threat to human and animal health. Progress in molecular biology has revealed new and significant challenges for AMR mitigation given the immense diversity of antibiotic resistance genes (ARGs), the complexity of ARG transfer, and the broad range of omnipresent factors contributing to AMR. Municipal, hospital and abattoir wastewater are collected and treated in wastewater treatment plants (WWTPs), where the presence of diverse selection pressures together with a highly concentrated consortium of pathogenic/commensal microbes create favourable conditions for the transfer of ARGs and proliferation of antibiotic resistant bacteria (ARB). The rapid emergence of antibiotic resistant pathogens of clinical and veterinary significance over the past 80 years has re-defined the role of WWTPs as a focal point in the fight against AMR. By reviewing the occurrence of ARGs in wastewater and sludge and the current technologies used to quantify ARGs and identify ARB, this paper provides a research roadmap to address existing challenges in AMR control via wastewater treatment. Wastewater treatment is a double-edged sword that can act as either a pathway for AMR spread or as a barrier to reduce the environmental release of anthropogenic AMR. State of the art ARB identification technologies, such as metagenomic sequencing and fluorescence-activated cell sorting, have enriched ARG/ARB databases, unveiled keystone species in AMR networks, and improved the resolution of AMR dissemination models. Data and information provided in this review highlight significant knowledge gaps. These include inconsistencies in ARG reporting units, lack of ARG/ARB monitoring surrogates, lack of a standardised protocol for determining ARG removal via wastewater treatments, and the inability to support appropriate risk assessment. This is due to a lack of standard monitoring targets and agreed threshold values, and paucity of information on the ARG-pathogen host relationship and risk management. These research gaps need to be addressed and re-search findings need to be transformed into practical guidance for WWTP operators to enable effective progress towards mitigating the evolution and spread of AMR. Refereed/Peer-reviewed

Pre-harvest sanitation of irrigation water has potential for reducing pathogen contamination of fresh produce. We compared the sanitizing effects of irrigation water containing neutral electrolyzed oxidizing water (EOW) or sodium hypochlorite (NaClO) on pre-harvest lettuce and baby spinach leaves artificially contaminated with a mixture of Escherichia coli, Salmonella Enteritidis and Listeria innocua (∼1 × 108 colony-forming units/mL each resuspended in water containing 100 mg/L dissolved organic carbon, simulating a splash-back scenario from contaminated soil/manure). The microbial load and leaf quality were assessed over 7 days, and post-harvest shelf life evaluated for 10 days. Irrigation with water containing EOW or NaClO at 50 mg/L free chlorine significantly reduced the inoculated bacterial load by ≥ 1.5 log10, whereas tap water irrigation reduced the inoculated bacterial load by an average of 0.5 log10, when compared with untreated leaves. There were no visual effects of EOW or tap water irrigation on baby spinach or lettuce leaf surfaces pre- or post-harvest, whereas there were obvious negative effects of NaClO irrigation on leaf appearance for both plants, including severe necrotic zones and yellowing/browning of leaves. Therefore, EOW could serve as a viable alternative to chemical-based sanitizers for pre-harvest disinfection of minimally processed vegetables. Refereed/Peer-reviewed

The presence of SARS-CoV-2 RNA in wastewater was first reported in March 2020. Over the subsequent months, the potential for wastewater surveillance to contribute to COVID-19 mitigation programmes has been the focus of intense national and international research activities, gaining the attention of policy makers and the public. As a new application of an established methodology, focused collaboration between public health practitioners and wastewater researchers is essential to developing a common understanding on how, when and where the outputs of this non-invasive community-level approach can deliver actionable outcomes for public health authorities. Within this context, the NORMAN SCORE “SARS-CoV-2 in sewage” database provides a platform for rapid, open access data sharing, validated by the uploading of 276 data sets from nine countries to-date. Through offering direct access to underpinning meta-data sets (and describing its use in data interpretation), the NORMAN SCORE database is a resource for the development of recommendations on minimum data requirements for wastewater pathogen surveillance. It is also a tool to engage public health practitioners in discussions on use of the approach, providing an opportunity to build mutual understanding of the demand and supply for data and facilitate the translation of this promising research application into public health practice. Validerad;2021;Nivå 2;2021-05-21 (alebob);Finansiär: För finansiärsinformation se Acknowledgements https://www.sciencedirect.com/science/article/pii/S0043135421003651?via%3Dihub#ack0001 DRIZZLE

This study assessed the effect of amendment of Australian soils (acidic, organic matter, Fe-rich, alkaline and silt-rich soils) with mobile platinum and gold (0 to 2000 mg kg−1) on soil respiration and the activity of seven key soil enzymes. Platinum amendment significantly reduced soil respiration at almost all concentrations (p < 0.05) in all soils except in organic matter-rich soil where up to 2-fold stimulation occurred at concentrations of up to 500 mg kg−1. Amendments with mobile Au-complexes also inhibited soil respiration irrespective of soil type, except for the Fe-rich soil. Platinum and Au amendments also impaired enzyme activities across most concentrations and soils, except alkaline soils. Overall, while mobile Au appears to be somewhat more toxic to soil microbial communities than Pt, toxicity levels appear to be largely determined by soil properties. Refereed/Peer-reviewed

With two thirds of the global population living in areas affected by water scarcity, wastewater reuse is actively being implemented or explored by many nations. There is a need to better understand the efficacy of recycled water treatment plants (RWTPs) for removal of human opportunistic pathogens and antimicrobial resistant microorganisms. Here, we used a suite of probe-based multiplex and SYBR green real-time PCR assays to monitor enteric opportunistic pathogens (EOPs; Acinetobacter baumannii, Arcobacter butzlieri, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Legionella spp., Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella Enteritidis, Streptococcus spp.) and antimicrobial resistance genes (ARGs; qnrS, blaSHV, blaTEM, blaGES, blaKPC, blaIMI, blaSME, blaNDM, blaVIM, blaIMP, blaOXA-48-like, mcr-1 and mcr-3) of key concern from an antimicrobial resistance (AMR), waterborne and foodborne disease perspective. The class 1 integron-integrase gene (intl1) was quantified as a proxy for multi-drug resistance. EOPs, intl1 and ARGs absolute abundance (DNA and RNA) and metabolic activity (RNA) was assessed through three RWTPs with differing treatment trains. Our results indicate that RWTPs produced high quality recycled water for non-potable reuse by removing > 95% of EOPs and ARGs, however, subpopulations of EOPs and ARGs survived disinfection and demonstrated potential to become actively growing members of the recycled water and distribution system microbiomes. The persistence of functional intl1 suggests that significant genetic recombination capacity remains in the recycled water, along with the likely presence of multi-drug resistant bacteria. Results provide new insights into the persistence and growth of EOPs, and prevalence and removal of ARGs in recycled water systems. These data will contribute towards the emerging evidence base of AMR risks in recycled water to inform quantitative risk-based policy development regarding water recycling schemes. Refereed/Peer-reviewed

Refereed/Peer-reviewed Occasional one-time tillage (strategic tillage, ST) is an effective tool for managing weeds and crop diseases in no-till and conversative farming systems. However, there is limited understanding of the impacts of ST on soil microbiome and their associated soil processes, particularly in dryland agriculture. This study aims to quantify the effect of one-off ST - after three years - on soil microbiomes and functions in a long-term no-till farming system under crop stubble and fertilizer management practices. The results showed that ST had marginal effects on microbial richness and diversity, enzyme activities, and catabolic function, but significantly affected the abundance of some microbial taxa (Actinobacteria, Firmicutes, Verrucomicrobia, Basidiomycota and Ascomycota) that are relevant to carbon (C) degradation. Stubble retention, regardless of tillage and fertilizer management, mainly increased the abundance of copiotrophs such as Proteobacteria (e.g., Rhizobiales) and Actinobacteria (e.g., Streptomyces and Micromonosporaceae), and affected Ascomycota and Basidiomycota. Among the management practices, stubble retention was the main factor that contributed to increased richness and diversity of the soil bacterial and fungal community. Supplementary fertilizer application, regardless of tillage and stubble management had minimal impact on bacterial and fungal richness and diversity, enzyme activity and catabolic function. The variation in bacterial community structure was influenced mainly by soil pH (c.a. 10%), while only a small but significant effect (< 7%; P = 0.001) was attributed to tillage and stubble management. Wheat grain yields ranged between 5 and 5.3 t ha-1 and were not affected by tillage, stubble, nor fertilizer management practices. Similarly, these management practices did not influence total soil C or nitrogen concentrations. Our findings show that strategic tillage, when used to address specific constraints in no-till systems in dryland agriculture, does not have a significant effect on total soil C, microbial ecology nor catabolic function.

Supplementing kindergarten children during a cold season with a prebiotic inulin-type fructans product with shorter and longer fructan chains has been shown to reduce febrile episodes requiring medical attention and to lower the incidence of sinusitis. These beneficial effects may be connected to the specific modulation of children’s gut microbiota. By applying quantitative and qualitative microbiota analysis this study aimed at characterising the gut microbiota composition and at exploring effects of prebiotic intervention on the gut microbiota during a 24-weeks intervention and during antibiotic treatment in healthy children. The study was a randomised, placebo-controlled trial with 258 healthy children aged 3 to 6 years consuming 6 g/day prebiotic inulin-type fructans or maltodextrin. During the course of the study, faecal samples were collected and subject to targeted qPCR analysis and phylogenetic profiling by multiplexed high throughput sequencing of the prokaryotic 16S rRNA gene PCR amplicons. The microbiota composition of the cohort could be clustered into three distinct constellations (enterotypes). Prebiotic intake resulted in a selective modulation of the gut microbiota composition. Relative abundance of Bifidobacterium was significantly higher in the prebiotic group (n=104) compared to control group (n=105) and this effect was found for all three enterotypes. Antibiotic administration decreased the relative abundance of Bifidobacterium in both groups. Nonetheless, children of the prebiotic group receiving antibiotic treatment displayed significantly higher levels of Bifidobacterium than children receiving the placebo control. Prebiotic supplementation induced specific changes in the gut microbiota composition of children aged 3 to 6 years. Moreover, it attenuated antibiotic-induced disturbances in the gut microbiota composition as shown by higher relative abundance of bifidobacteria at the end of the antibiotic treatment in the prebiotic group. With the previously reported benefits on immune function, the study contributes to the evidence on the immune-modulating effects of prebiotics through gut microbiota modifications. The study was registered as NCT03241355 (https://clinicaltrials.gov/show/NCT03241355). Refereed/Peer-reviewed

The objective of this study was to test the original speciation of silver (Ag) in eight different commercially available personal care products and investigate the chemical transformation of Ag during exposure to two types of synthetic greywater. The antimicrobial activity of the products was examined to determine the relationship between Ag content and speciation with the antibacterial functionality of the products. The Ag content of each product was quantified and X-ray absorption near-edge structure (XANES) analysis was used to investigate the initial speciation in the products and the changes occurring upon mixture with greywater. The results showed that the total Ag concentration in the products ranged from 17 to 30 mgkg−1, and was usually below the value reported on the label. Analyses revealed the complexity of Ag speciation in these products and highlighted the importance of characterisation studies to help elucidate the potential risks of nano-Ag in the environment. The antibacterial results confirmed that the antibacterial efficacyof the products depends on the concentration, form and speciation of Ag in the products, but is also significantly affected by product formulation. For instance, many of the products contained additional bactericidal ingredients, making it difficult to determine how much of the bactericidal effect was due directly to the Ag content/species. This paper offers some suggestions for standard methodologies to facilitate cross-comparison of potential risks across different studies and nano-enabled products. Refereed/Peer-reviewed

Wastewater is a complex matrix containing a wide range of chemical and biological markers of human activity. Relating concentrations of these "waste" materials in wastewater influent streams to population-scale use, consumption, or rates of exposure, can provide important qualitative or quantitative information on the activity of inhabitants within a given wastewater catchment. Many publications in this field of study have focussed on the usage of pharmaceuticals, illicit drugs, tobacco and alcohol. However, many other potential applications are emerging which can contribute useful knowledge on human health, exposure to industrial chemicals, infectious diseases or pathogens and antibiotic resistance. This review summarises the established wastewater based epidemiology (WBE) biomarkers, and presents a critical review of the current capabilities of WBE. We further discuss possible future strategies and challenges anticipated in analysing wastewater to measure chemical markers of population health as well as biological markers of microbial exposure and disease. (c) 2018 Elsevier B.V. All rights reserved.

Synchrotron-based X-ray analysis of living wheat leaves showed that foliar-applied ZnEDTA is taken up as a ligand complex, and typical Zn agricultural application rates may induce localized toxicity, Foliar application of zinc (Zn) to crops is an effective way to increase the grain concentration of Zn. However, the development of more efficient foliar Zn fertilizers is limited by a lack of knowledge regarding the distribution, mobility, and speciation of Zn in leaves once it is taken up by the plant. We performed an experiment using radiolabelled Zn (65Zn), and in situ time-resolved elemental imaging using synchrotron X-ray fluorescence microscopy (XFM), to investigate the behaviour of two commonly used Zn foliar fertilizers (Zn sulphate and ZnEDTA) in wheat (Triticum aestivum) leaves. Both experiments showed that Zn had limited mobility in leaves, moving

The World Health Organization Global Action Plan recommends integrated surveillance programs as crucial strategies for monitoring antibiotic resistance. Although several national surveillance programs are in place for clinical and veterinary settings, no such schemes exist for monitoring antibiotic-resistant bacteria in the environment. In this transnational study, we developed, validated, and tested a low-cost surveillance and easy to implement approach to evaluate antibiotic resistance in wastewater treatment plants (WWTPs) by targeting cefotaxime-resistant (CTX-R) coliforms as indicators. The rationale for this approach was: i) coliform quantification methods are internationally accepted as indicators of fecal contamination in recreational waters and are therefore routinely applied in analytical labs; ii) CTX-R coliforms are clinically relevant, associated with extended-spectrum β-lactamases (ESBLs), and are rare in pristine environments. We analyzed 57 WWTPs in 22 countries across Europe, Asia, Africa, Australia, and North America. CTX-R coliforms were ubiquitous in raw sewage and their relative abundance varied significantly (

The growing health and economic burden posed by foodborne pathogens has stimulated global interest in the development of safe, affordable, effective and environmentally-sustainable irrigation water treatment technologies. This review critically compares the potential of existing and emerging methods for disinfection of irrigation water to reduce pathogenic microbial loads on high-risk vegetables and minimally processed fresh produce. We explore electrochemical disinfection and electrolyzed oxidizing water as alternatives to traditional chlorination, and identify hydrodynamic cavitation as an emerging disinfection strategy worthy of further investigation in this context. In addition, we assess the state of the knowledge regarding the impact of current water sanitation strategies on the ecological dynamics of plant and soil microbes and the potential induction of viable but nonculturable cells. Increased research in these areas could translate into substantial improvement in the overall quality and value of fresh produce, while maintaining environmentally-sustainable irrigation water usage. Refereed/Peer-reviewed

There is increasing demand for safe and effective sanitizers for irrigation water disinfection to prevent transmission of foodborne pathogens to fresh produce. Here we compared the efficacy of pH-neutral electrolyzed oxidizing water (EOW), sodium hypochlorite (NaClO) and chlorine dioxide (ClO2) against single and mixed populations of E. coli, Listeria and Salmonella under a range of pH and organic matter content. EOW treatment of the mixed bacterial suspension resulted in a dose-dependent (10) reduction of the microbial load in water devoid of organic matter under the range of pH conditions tested (pH, 6.0, 7.0, 8.4 and 9.2). The efficacy of EOW containing 5 mg/L free chlorine was unaffected by increasing organic matter, and compared favourably with equivalent concentrations of NaClO and ClO2. EOW at 20 mg/L free chlorine was more effective than NaClO and ClO2 in reducing bacterial populations in the presence of high (20–100 mg/L) dissolved organic carbon, and no regrowth or metabolic activity was observed for EOW-treated bacteria at this concentration upon reculturing in rich media. Thus, EOW is as effective or more effective than other common chlorine-based sanitizers for pathogen reduction in contaminated water. EOW’s other characteristics, such as neutral pH and ease of handling, indicate its suitability for fresh produce sanitation.

Ammonia (NH3) volatilization is considered as one of the major mechanisms responsible for the loss of nitrogen (N) from soil-plant systems worldwide. This study investigated the effect of biochar amendment to a calcareous soil (pH 7.8) on NH3 volatilization and plant N uptake. In particular, the effect of biochar's feedstock and application rate on both NH3 volatilization and plant growth were quantified using a specially designed closed chamber system. Two well-characterized biochars prepared from poultry manure (PM-BC) and green waste compost (GW-BC) were applied to the soil (0, 0.5, 1, 1.5 and 2% w/w equivalent to 0, 7.5, 15, 22 and 30 t ha−1) and wheat (Triticum aestivum, variety: Calingiri) was grown for 30 days. Both PM-BC and GW-BC decreased NH3 volatilization to a similar degree (by 47 and 38%, respectively), in the soil-plant system compared to the unamended control. Higher plant biomass production of up to 70% was obtained in the closed chamber systems with the addition of biochar. The increase in plant biomass was due to the reduction in N loss as NH3 gas, thereby increasing the N supply to the plants. Plant N uptake was improved by as much as 58% with biochar addition when additional NPK nutrients were supplied to the soil. This study demonstrates that the application of biochars can mitigate NH3 emission from calcareous agricultural cropping soil and that the retained N is plant-available and can improve wheat biomass yield Refereed/Peer-reviewed

With the growing availability and use of copper-based nanomaterials (Cu-NMs), there is increasing concern regarding their release and potential impact on the environment. In this study, the short-term (≤ 5 d) aging profile and the long-term (135 d) speciation of dissolved Cu, copper oxide, and copper sulfide nanoparticles (CuO-NPs and CuS-NPs) were investigated in five different soils using X-ray absorption spectroscopy. Soil pH was found to strongly influence the short-term chemistry of the Cu-NMs added at 100 mg kg ⁻¹ above background. Low pH soils promoted rapid dissolution of CuO-NPs that effectively aligned their behavior to that of dissolved Cu within 3 d. In higher pH soils, CuO-NPs persisted longer due to slower dissolution in the soil and resulted in contrasting short-term speciation compared with dissolved Cu, which formed copper hydroxides and carbonates that were reflective of the soil chemistry. Organic matter appeared to slow the dissolution process, but in the long term, the speciation of Cu added as dissolved Cu, CuO-NPs, and CuS-NPs were found to be same for each soil. The results imply that, in the short term, Cu-NMs may exhibit unique behavior in alkaline soils compared with their conventional forms (e.g., in the event of an adverse leaching event), but in the long term (≥ 135 d), their fates are dictated by the soil properties, are independent of the initial Cu form, and are likely to present minimal risk of nanospecific Cu-NM impact in the soil environment for the concentration studied here. Refereed/Peer-reviewed

Elevated levels of trace metal(loid)s reduce plant growth, both in soils contaminated by industrial activities and in acid agricultural soils. Although the adverse effects of trace metal(loid)s have long been recognized, there remains much unknown both about their behavior in soils, their toxicity to plants, and the mechanisms that plants use to tolerate elevated concentrations. Synchrotronbased approaches are being utilized increasingly in soil-plant systems to examine toxic metal(loid)s. In the present review, brief consideration is given to the theory of synchrotron radiation. Thereafter, we review the use of synchrotron-based approaches for the examination of various trace metal(loid)s in soil-plant systems, including aluminum, chromium, manganese, cobalt, nickel, copper, zinc, arsenic, selenium , and cadmium. Within the context of this review, X-ray absorption spectroscopy (XAS) and X-ray fluorescence microscopy (m-XRF) are of particular interest. These techniques can provide in situ analyses of the distribution and speciation of metal(loid)s in soil-plant systems. The information presented here serves not only to understand the behavior of trace metals in soil-plant systems, but also to provide examples of the potential applications of synchrotron radiation that can be used to advantage in other studies. Refereed/Peer-reviewed

Environmental contextZinc, an essential micronutrient often applied to crops as a fertiliser, can be difficult to analyse in plants due to limitations of conventional techniques. Here, we use radiotracers and a non-destructive imaging technique to visualise how zinc applied as a nanofertiliser moves within wheat plants over time. This is an important step towards developing cost-effective fertilisers to help solve one of the world’s most widespread plant deficiencies. AbstractZinc (Zn) deficiency affects half of the world’s arable soil and one-third of the world’s human population. Application of Zn foliar fertilisers to cereal crops can be an effective way to increase grain Zn content; however, commonly used formulations can scorch the leaf (e.g. soluble Zn salts) or are prohibitively expensive (e.g. chelated Zn, ZnEDTA). Zinc oxide nanoparticles (ZnO-NPs) may offer an efficient and cost-effective alternative, but little is known regarding the mechanisms of Zn uptake and translocation within the plant. Foliar-applied Zn is analytically challenging to detect, locate and quantify, as it is omnipresent. Furthermore, any single analytical technique does not have the detection limit or spatial resolution required. In this study, the uptake and mobility of foliar-applied ZnEDTA, ZnO-NPs and ZnO microparticles (ZnO-MPs) to wheat (Triticum aestivum L.) were investigated using inductively coupled plasma mass spectroscopy (ICP-MS), synchrotron-based X-ray fluorescence microscopy (XFM) and radiotracing techniques using 65Zn-labelled formulations. The three techniques were compared to highlight limitations and advantages of each. We also report, for the first time, a novel time-resolved invivo autoradiography imaging technique that can be used to visualise 65Zn in live plants treated with foliar applications of 65ZnO-NPs and MPs. The images were supplemented by gamma spectroscopy analysis for quantification. The results of this study provide important insights into the analytical challenges faced when investigating foliar-applied Zn nanofertilisers in plants. Potential solutions using nuclear techniques are also discussed, which in turn may ultimately lead to the development of more efficient foliar fertilisers.

Several studies have suggested that the majority of iron (Fe) and zinc (Zn) in wheat grains are associated with phytate, but a nuanced approach to unravel important tissue-level variation in element speciation within the grain is lacking. Here, we present spatially resolved Fe-speciation data obtained directly from different grain tissues using the newly developed synchrotron-based technique of X-ray absorption near-edge spectroscopy imaging, coupling this with high-definition μ-X-ray fluorescence microscopy to map the co-localization of essential elements. In the aleurone, phosphorus (P) is co-localized with Fe and Zn, and X-ray absorption near-edge structure imaging confirmed that Fe is chelated by phytate in this tissue layer. In the crease tissues, Zn is also positively related to P distribution, albeit less so than in the aleurone. Speciation analysis suggests that Fe is bound to nicotianamine rather than phytate in the nucellar projection, and that more complex Fe structures may also be present. In the embryo, high Zn concentrations are present in the root and shoot primordium, co-occurring with sulfur and presumably bound to thiol groups. Overall, Fe is mainly concentrated in the scutellum and co-localized with P. This high resolution imaging and speciation analysis reveals the complexity of the physiological processes responsible for element accumulation and bioaccessibility.

Utilization of nanoparticles (NP) in agriculture as fertilizers or pesticides requires an understanding of the NP properties influencing their interactions with plant roots. To evaluate the influence of the solubility of Cu-based NP on Cu uptake and NP association with plant roots, wheat seedlings were hydroponically exposed to 1 mg/L of Cu NPs with different solubilities [CuO, CuS, and Cu(OH)

This article discusses the potential ramifications of the COVID-19 pandemic on waste and wastewater services, focusing on critical points where alternative operating procedures or additional mitigation measures may be advisable. Key concerns are (i) the long half-life of the virus on materials such as waste containers, bags, and in wastewater, and (ii) possible transmission via contaminated waste surfaces and aerosols from wastewater systems. There are opportunities to further the science of wastewater-based epidemiology by monitoring viral RNA in wastewater to assess disease prevalence and spread in defined populations, which may prove beneficial for informing COVID-19 related public health policy., Graphical abstract Image 1

Refereed/Peer-reviewed

Increasing commercial use of nanosilver has focussed attention on the fate of silver (Ag) in the wastewaterrelease pathway. This paper reports the speciation and lability of Ag in archived, stockpiled, andcontemporary biosolids from the UK, USA and Australia, and indicates that biosolids Ag concentrationshave decreased significantly over recent decades. XANES revealed the importance of reduced-sulfurbinding environments for Ag speciation in materials ranging from freshly produced sludge to biosolidsweathered under ambient environmental conditions for more than 50 years. Isotopic dilution with110mAg showed that Ag was predominantly non-labile in both fresh and aged biosolids (13.7% meanlability), with E-values ranging from 0.3 to 60 mg/kg and 5 mM CaNO3 extractable Ag from 1.2 to 609 mg/kg (0.002e3.4% of the total Ag). This study indicates that at the time of soil application, biosolids Ag willbe predominantly Ag-sulfides and characterised by low isotopic lability. Refereed/Peer-reviewed

Silver nanoparticles (Ag-NPs) are used in a wide variety of products, prompting concerns regarding their potential environmental impacts. To accurately determine the toxicity of Ag-NPs it is necessary to differentiate between the toxicity of the nanoparticles themselves and the toxicity of ionic silver (Ag) released from them. This is not a trivial task given the reactive nature of Ag in solution, and its propensity for both adsorption and photo reduction. In the experiments reported here, we quantified the loss of silver from test solutions during standard ecotoxicity testing conducted using a variety of different test container materials and geometries. This sensitive 110mAg isotope tracing method revealed a substantial underestimation of the toxicity of dissolved Ag to the green algae Pseudokirchneriella subcapitata when calculated only on the basis of the initial test concentrations. Furthermore, experiments with surface-functionalized Ag-NPs under standard algal growth inhibition test conditions also demonstrated extensive losses of Ag-NPs from the solution due to adsorption to the container walls, and the extent of loss was dependent on Ag-NP surface-functionality. These results hold important messages for researchers engaged in both environmental and human nanotoxicology testing, not only for Ag-NPs but also for other NPs with various tailored surface chemistries, where these phenomena are recognized but are also frequently disregarded in the experimental design and reporting. Refereed/Peer-reviewed

© 2015 Elsevier Ltd. Titanium dioxide nanoparticles (TiO2 NPs) are currently one of the most prolifically used nanomaterials, resulting in an increasing likelihood of release to the environment. This is of concern as the potential toxicity of TiO2 NPs has been investigated in several recent studies. Research into their fate and behaviour once entering the environment is urgently needed to support risk assessment and policy development. In this study, we used a multi-method approach combining light scattering and field-flow fractionation techniques to assess both the aggregation behaviour and aggregate structure of TiO2 NPs in different river waters. Results showed that both the aggregate size and surface-adsorbed dissolved organic matter (DOM) were strongly related to the initial DOM concentration of the tested waters (i.e. R2>0.90) suggesting that aggregation of TiO2 NPs is controlled by the presence and concentration of DOM. The conformation of the formed aggregates was also found to be strongly related to the surface-adsorbed DOM (i.e. R2>0.95) with increasing surface-adsorbed DOM leading to more compact structures. Finally, the concentration of TiO2 NPs remaining in the supernatant after sedimentation of the larger aggregates was found to decrease proportionally with both increasing IS and decreasing DOM concentration, resulting in more than 95% sedimentation in the highest IS sample.

To understand the biogeochemistry of nutrients and contaminants in environmental media, their speciation and behavior under different conditions and at multiple scales must be determined. Synchrotron radiation-based X-ray techniques allow scientists to elucidate the underlying mechanisms responsible for nutrient and contaminant mobility, bioavailability, and behavior. The continuous improvement of synchrotron light sources and X-ray beamlines around the world has led to a profound transformation in the field of environmental biogeochemistry and, subsequently, to significant scientific breakthroughs. Following this introductory paper, this special collection includes 10 papers that either present targeted reviews of recent advancements in spectroscopic methods that are applicable to environmental biogeochemistry or describe original research studies conducted on complex environmental samples that have been significantly enhanced by incorporating synchrotron radiation-based X-ray technique(s). We believe that the current focus on improving the speciation of ultra-dilute elements in environmental media through the ongoing optimization of synchrotron technologies (e.g., brighter light sources, improved monochromators, more efficient detectors) will help to significantly push back the frontiers of environmental biogeochemistry research. As many of the relevant techniques produce extremely large datasets, we also identify ongoing improvements in data processing and analysis (e.g., software improvements and harmonization of analytical methods) as a significant requirement for environmental biogeochemists to maximize the information that can be gained using these powerful tools. Refereed/Peer-reviewed

Microbial fuel cell (MFC) and its reactor systems have been intensively investigated for energy production and wastewater treatment using wild bacterial consortia. Yet, there is lack of detailed studies on understanding how multiple wild microorganisms could alter bioelectrochemical reactions in MFC for degrading toxic organic contaminants and generating electricity from industrial wastewater. Hence, this study evaluates the microbial community and bioelectrochemical activities in a lab-scale MFC reactor inoculated by petrochemical industrial microbial consortium (IMC) and domestic microbial consortium (DMC), aiming to enhance MFC performance for degrading 2,4-dichlorophenol (2,4-DCP) and producing electricity. Cutting-edge microbiology analysis techniques were used for identifying microbial community in suspension and biofilm in the IMC and DMC inoculated MFC systems. Research focused on evaluating how the variable microbial population and 2,4-DCP feeding could affect bioelectrochemical activities and MFC performance. Arcobacter, Aeromonas, Pseudomonas, Acinetobacter, Cloacibacterium, and Shewanella sp. in DMC were found to be important bacteria for 2,4-DCP degradation while Bacillus sp. dominated IMC contributing to higher electricity production. This would be the first discovery of Cloacibacterium sp. contributing phenol degradation in MFC. IMC-MFC reactor performed well in producing high 156 mA/m 2 current density with 41% phenolic degradation, while DMC-MFC showed promising 62% 2,4-DCP reduction and 123 mA/m 2 current production. MFC systems performed highly comparable 2,4-DCP degradation efficiency than the conventional anaerobic biodegradation. These results demonstrate that wastewater-inoculated MFCs can be capable of simultaneous energy generation and phenolic degradation and provide new insights that may assist with future MFC optimisation. Refereed/Peer-reviewed