Pyrolysis of Two Perfluoroalkanesulfonates (PFSAs) and PFSA-Laden Granular Activated Carbon (GAC): Decomposition Mechanisms and the Role of GAC.

Thermal treatment of perfluoroalkyl and polyfluoroalkyl substances (PFASs) presents a promising opportunity to halt the PFAS cycle. However, how co-occurring materials such as granular activated carbon (GAC) influence thermal decomposition products of PFASs, and underlying mechanisms remain unclear. We studied the pyrolysis of two potassium salts of perfluoroalkanesulfonates (PFSAs, CFSOK), perfluorobutanesulfonate (PFBS-K), and perfluorooctanesulfonate (PFOS-K), with or without GAC.

Dual feedback inhibition of ATP-dependent caffeate activation economizes ATP in caffeate-dependent electron bifurcation.

Unlabelled: The acetogen couples caffeate reduction with ferredoxin reduction and NADH oxidation via electron bifurcation, providing additional reduced ferredoxin for energy conservation and cell synthesis. Caffeate is first activated by an acyl-CoA synthetase (CarB), which ligates CoA to caffeate at the expense of ATP. After caffeoyl-CoA is reduced to hydrocaffeoyl-CoA, the CoA moiety in hydrocaffeoyl-CoA could be recycled for caffeoyl-CoA synthesis by an ATP-independent CoA transferase (CarA) to save energy.

Synergistic material-microbe interface toward deeper anaerobic defluorination.

Per- and polyfluoroalkyl substances (PFAS), particularly the perfluorinated ones, are recalcitrant to biodegradation. By integrating an enrichment culture of reductive defluorination with biocompatible electrodes for the electrochemical process, a deeper defluorination of a C-perfluorinated unsaturated PFAS was achieved compared to the biological or electrochemical system alone. Two synergies in the bioelectrochemical system were identified: i) The in-series microbial-electrochemical defluorination and ii) the electrochemically enabled microbial defluorination of intermediates.

Electron bifurcation and fluoride efflux systems implicated in defluorination of perfluorinated unsaturated carboxylic acids by spp.

Enzymatic cleavage of C─F bonds in per- and polyfluoroalkyl substances (PFAS) is largely unknown but avidly sought to promote systems biology for PFAS bioremediation. Here, we report the reductive defluorination of α, β-unsaturated per- and polyfluorocarboxylic acids by spp. The microbial defluorination products were structurally confirmed and showed regiospecificity and stereospecificity, consistent with their formation by enzymatic reactions.

Promotive Effects of Chloride and Sulfate on the Near-Complete Destruction of Perfluorocarboxylates (PFCAs) in Brine via Hydrogen-tuned 185-nm UV Photolysis: Mechanisms and Kinetics.

Hydrogen-tuned 185 nm vacuum ultraviolet (VUV/H) photolysis is an emerging technology to destroy per- and polyfluoroalkyl substance (PFAS) in brine. This study discovered the promotive effects of two major brine anions, i.e.

Dissemination of antimicrobial resistance in agricultural ecosystems following irrigation with treated municipal wastewater.

The spread of antimicrobial resistance (AMR) in agricultural systems via irrigation water is a serious public health issue as it can be transmitted to humans through the food chain. Therefore, understanding the dissemination routes of antibiotic resistance genes (ARGs) in agricultural systems is crucial for the assessment of health risks associated with eating fresh vegetables such as spinach and radish irrigated with treated municipal wastewater (TMW). In this study, we investigated the bacterial community structure and resistome in the soil-plant-earthworm continuum after irrigation of spinach and radish with TMW containing the antibiotics trimethoprim (TMP), sulfamethoxazole (SMZ), and sulfapyridine (SPD) using 16S rRNA gene sequencing and high throughput quantitative PCR (HT-qPCR).

Oxidative Transformation of Nafion-Related Fluorinated Ether Sulfonates: Comparison with Legacy PFAS Structures and Opportunities of Acidic Persulfate Digestion for PFAS Precursor Analysis.

The total oxidizable precursor (TOP) assay has been extensively used for detecting PFAS pollutants that do not have analytical standards. It uses hydroxyl radicals (HO) from the heat activation of persulfate under alkaline pH to convert H-containing precursors to perfluoroalkyl carboxylates (PFCAs) for target analysis. However, the current TOP assay oxidation method does not apply to emerging PFAS because (i) many structures do not contain C-H bonds for HO attack and (ii) the transformation products are not necessarily PFCAs.

Substantial defluorination of polychlorofluorocarboxylic acids triggered by anaerobic microbial hydrolytic dechlorination.

Chlorinated polyfluorocarboxylic acids (Cl-PFCAs) derived from the widely used chlorotrifluoroethylene (CTFE) polymers and oligomers may enter and influence the aquatic environment. Here, we report significant defluorination of Cl-PFCAs by an anaerobic microbial community via novel pathways triggered by anaerobic microbial dechlorination. Cl-PFCAs first underwent microbial reductive, hydrolytic, and eliminative dechlorination, and it was the hydrolytic dechlorination that led to significant spontaneous defluorination.

Electron-bifurcation and fluoride efflux systems in spp. drive defluorination of perfluorinated unsaturated carboxylic acids.

Enzymatic cleavage of C-F bonds in per- and polyfluoroalkyl substances (PFAS) is largely unknown but avidly sought to promote systems biology for PFAS bioremediation. Here, we report the reductive defluorination of α, β-unsaturated per- and polyfluorocarboxylic acids by spp. Two critical molecular features in species enabling reductive defluorination are (i) a functional fluoride efflux transporter (CrcB) and (ii) an electron-bifurcating caffeate reduction pathway (CarABCDE).

Dissemination of antibiotic resistance genes through soil-plant-earthworm continuum in the food production environment.

Treated municipal wastewater (TMW) can provide a reliable source of irrigation water for crops, which is especially important in arid areas where water resources are limited or prone to drought. Nonetheless, TMW may contain residual antibiotics, potentially exposing the crops to these substances. The goal of this study was to investigate the dissemination of antibiotics resistance genes (ARGs) in the soil-plant-earthworm continuum after irrigation of spinach and radish plants with TMW containing trimethoprim, sulfamethoxazole, and sulfapyridine in a greenhouse experiment, followed by feeding of earthworms with harvested plant materials.

Pneumatic nano-sieve for CRISPR-based detection of drug-resistant bacteria.

The increasing prevalence of antibiotic-resistant bacterial infections, particularly methicillin-resistant (MRSA), presents a significant public health concern. Timely detection of MRSA is crucial to enable prompt medical intervention, limit its spread, and reduce antimicrobial resistance. Here, we introduce a miniaturized nano-sieve device featuring a pneumatically-regulated chamber for highly efficient MRSA purification from human plasma samples.

Pneumatic Nano-Sieve for CRISPR-based Detection of Drug-resistant Bacteria.

The increasing prevalence of antibiotic-resistant bacterial infections, particularly methicillin-resistant Staphylococcus aureus (MRSA), presents a significant public health concern. Timely detection of MRSA is crucial to enable prompt medical intervention, limit its spread, and reduce antimicrobial resistance. Here, we introduce a miniaturized nano-sieve device featuring a pneumatically-regulated chamber for highly efficient MRSA purification from human plasma samples.

Retrieval, Selection, and Evaluation of Chemical Property Data for Assessments of Chemical Emissions, Fate, Hazard, Exposure, and Risks.

Reliable chemical property data are the key to defensible and unbiased assessments of chemical emissions, fate, hazard, exposure, and risks. However, the retrieval, evaluation, and use of reliable chemical property data can often be a formidable challenge for chemical assessors and model users. This comprehensive review provides practical guidance for use of chemical property data in chemical assessments.

Transformation of Graphitic Carbon Nitride by Reactive Chlorine Species: "Weak" Oxidants Are the Main Players.

Graphitic carbon nitride (g-CN) nanomaterials hold great promise in diverse applications; however, their stability in engineering systems and transformation in nature are largely underexplored. We evaluated the stability, aging, and environmental impact of g-CN nanosheets under the attack of free chlorine and reactive chlorine species (RCS), a widely used oxidant/disinfectant and a class of ubiquitous radical species, respectively. g-CN nanosheets were slowly oxidized by free chlorine even at a high concentration of 200-1200 mg L, but they decomposed rapidly when ClO· and/or Cl were the key oxidants.

Benzimidazole fungicide biotransformation by comammox Nitrospira bacteria: Transformation pathways and associated proteomic responses.

Benzimidazole fungicides are frequently detected in aquatic environments and pose a serious health risk. Here, we investigated the metabolic capacity of the recently discovered complete ammonia-oxidizing (comammox) Nitrospira inopinata and kreftii to transform a representative set of benzimidazole fungicides (i.e.

Dissemination of antibiotics through the wastewater-soil-plant-earthworm continuum.

Under the ongoing climate change scenario, treated municipal wastewater (TMW) is a potential candidate for irrigated agriculture but may result in the exposure of agricultural environments to antibiotics. We studied the transfers of trimethoprim, sulfamethoxazole, and sulfapyridine in the TMW-soil-plant-earthworm continuum under greenhouse/laboratory conditions. Irrigation of potted spinach and radish with as-collected TMW resulted in no transfers of antibiotics into soil or plants owing to their low concentrations in the tertiary-treated TMW.

Understanding point-of-use tap water quality: From instrument measurement to intelligent analysis using sample filtration.

In most cases, point-of-use tap water quality is not routinely monitored due to widely-dispersed sampling sites and the costly tests. Although previous studies have revealed the variation of drinking water quality during distribution in municipal networks, the influence of aging pipes in buildings on quality is still unknown and this makes it difficult for water utilities to conduct regular maintenance. Herein, we have undertaken a survey of tap water samples across 8 districts in Beijing (China) to evaluate the potential effects of pipe age on point-of-use water quality, including turbidity, organic matter characteristics, and bacterial community.

Microbial Defluorination of Unsaturated Per- and Polyfluorinated Carboxylic Acids under Anaerobic and Aerobic Conditions: A Structure Specificity Study.

The recently discovered microbial reductive defluorination of two C branched and unsaturated fluorinated carboxylic acids (FCAs) provided valuable insights into the environmental fate of per- and polyfluoroalkyl substances (PFASs) and potential bioremediation strategies. However, a systematic investigation is needed to further demonstrate the role of C═C double bonds in the biodegradability of unsaturated PFASs. Here, we examined the structure-biodegradability relationships of 13 FCAs, including nine commercially available unsaturated FCAs and four structurally similar saturated ones, in an anaerobic defluorinating enrichment and an activated sludge community.

Structure-Specific Aerobic Defluorination of Short-Chain Fluorinated Carboxylic Acids by Activated Sludge Communities.

Per- and polyfluoroalkyl substances (PFAS) are a large group of manmade chemicals that impose emerging environmental concerns. Among them, short-chain per- and polyfluorinated carboxylic acids represent an important subgroup used as building blocks of biologically active chemicals and functional materials. Some are also considered PFAS alternatives, and some could be byproducts of the physicochemical treatment of PFAS.

Accelerated Degradation of Perfluorosulfonates and Perfluorocarboxylates by UV/Sulfite + Iodide: Reaction Mechanisms and System Efficiencies.

The addition of iodide (I) in the UV/sulfite system (UV/S) significantly accelerated the reductive degradation of perfluorosulfonates (PFSAs, CFSO) and perfluorocarboxylates (PFCAs, CFCOO). Using the highly recalcitrant perfluorobutane sulfonate (CFSO) as a probe, we optimized the UV/sulfite + iodide system (UV/S + I) to degrade = 1-7 PFCAs and = 4, 6, 8 PFSAs. In general, the kinetics of per- and polyfluoroalkyl substance (PFAS) decay, defluorination, and transformation product formations in UV/S + I were up to three times faster than those in UV/S.

Siderophores provoke extracellular superoxide production by Arthrobacter strains during carbon sources-level fluctuation.

Superoxide and other reactive oxygen species (ROS) shape microbial communities and drive the transformation of metals and inorganic/organic matter. Taxonomically diverse bacteria and phytoplankton produce extracellular superoxide during laboratory cultivation. Understanding the physiological reasons for extracellular superoxide production by aerobes in the environment is a crucial question yet not fully solved.

Defluorination of Omega-Hydroperfluorocarboxylates (ω-HPFCAs): Distinct Reactivities from Perfluoro and Fluorotelomeric Carboxylates.

Omega-hydroperfluorocarboxylates (ω-HPFCAs, CF-(CF)-COO) are commercially available in bulk quantities and have been applied in agrochemicals, fluoropolymer production, and semiconductor coating. In this study, we used kinetic measurements, theoretical calculations, model compound experiments, and transformation product analyses to reveal novel mechanistic insights into the reductive and oxidative transformation of ω-HPFCAs. Like perfluorocarboxylates (PFCAs, CF-(CF)-COO), the direct linkage between CF- and -COO enables facile degradation under UV/sulfite treatment.