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The growing accumulation of plastic waste in the environment has created novel habitats known as the "plastisphere", where microorganisms can thrive. Concerns are rising about the potential for pathogenic microorganisms to proliferate in the plastisphere, posing risks to human health. However, our knowledge regarding the virulence and pathogenic potential of these microorganisms in the plastisphere remains limited. This study quantified the abundance of virulence factor genes (VFGs) in the plastisphere and its surrounding environments (water and soil) to better assess pathogenic risks. Our findings revealed a selective enrichment of VFGs in the plastisphere, which were attributed to the specific microbial community assembled. The presence of arsenic and ciprofloxacin in the plastisphere exerted additional co-selective pressures, intensifying the enrichment of VFGs. Notably, VFGs that encoded multiple functions or enhanced the survival of host microorganisms (e.g., encoding adherence functions) tended to accumulate in the plastisphere. These versatile and environmentally adaptable VFGs are more likely to be favored by bacteria in the environment, warranting increased attention in future investigations due to their potential for widespread dissemination. In terms of virulence and pathogenicity, this research offers new insights into evaluating pathogen-related risks in the plastisphere. [Display omitted] • The VFGs is selective enrichment driven by unique microbial community in plastisphere. • The transfer of VFGs from soil to water escalated microbiological risks in plastisphere. • Co-pollution of arsenic and ciprofloxacin amplified the VFGs enrichment in plastisphere. • Multifunctional and adaptable VFGs tended to accumulate in the environment. [ABSTRACT FROM AUTHOR]

Heavy metal ions and organic pollutants discharged into various water bodies have caused serious water pollution, and the efficient removal of these contaminants remains a challenge. Here, we report a novel MXene/poly-melamine-formaldehyde (PMF) composite membrane, in which the PMF particles serve as spacers, and the –NH 2 groups of PMF and the hydroxyl groups of MXene nanosheets have a synergistic effect on the adsorption of pollutants, and the crosslinking of glutaraldehyde inhibits the swelling of the composite membrane. The MXene/PMF composite membrane with 83.7% PMF particle loading displays a water permeability of 381.2 L m−2 h−1 bar−1 (405% that of MXene membrane) and excellent adsorption ability. In static adsorption, the removal rates of Zn2+, Pb2+, phenol, and crystal violet reach 96.2%, 91.7%, 99.1%, and 96.4% respectively, 20∼100% higher than those of MXene membranes. In dynamic adsorption, the breakthrough volumes of the membrane for 2 ppm p-nitrophenol solution and methyl blue solution reach 75 mL (about 8500 times membrane volume) and 350 mL (about 39800 times membrane volume), and the saturation volumes are 1500 mL and 5000 mL, respectively. After cyclic adsorption/desorption for four times, the removal rate of the membranes still maintains above 90%. This work provides an efficient composite membrane for removing pollutants from wastewater. [Display omitted] • A novel MXene/poly-melamine-formaldehyde (PMF) composite membrane are prepared. • The introduction of PMF particles widens the transmission channel and increases water permeance. • PMF and MXene nanosheets have a synergistic effect on the adsorption of pollutants. • Removal rates of Zn2+, Pb2+, phenol and crystal violet by MXene composite membranes are above 90%. • After 4 times of use, the removal rate of pollutant of composite membrane is above 90%. [ABSTRACT FROM AUTHOR]

Chlorine dioxide (ClO 2) has emerged as a broad-spectrum, safe, and effective disinfectant due to its high oxidation efficiency and reduced formation of organochlorinated by-products during application. This article provides an updated overview of ClO 2 -based oxidation processes used in water treatment. A systematic review of scientific information and experimental data on ClO 2 -based water purification procedures is presented. Concerning ClO 2 -based oxidation derivative problems, the pros and cons of ClO 2 -based combined processes are assessed and disinfection by-product (DBP) control approaches are proposed. The kinetic and mechanistic data on ClO 2 reactivity towards micropollutants are discussed. ClO 2 selectively reacts with electron-rich moieties (anilines, phenols, olefins, and amines) and eliminates certain inorganic ions and microorganisms with high efficiency. The formation of chlorite and chlorate during the oxidation process is a crucial concern when utilizing ClO 2. Future applications include the combination of ClO 2 with ferrous ions, activated carbon, ozone, UV, visible light, or persulfate processes. The combined process can reduce by-product generation while still ensuring ClO 2 sterilization and disinfection. Overall, this research could provide useful information and new insights into the application of ClO 2 -based technologies. [Display omitted] • ClO 2 application derivative problems and DBPs control methods are discussed. • UV/ClO 2 process can achieve high-efficiency disinfection and reuse ClO 2 -. • The mechanistic information on combination process based on ClO 2 is analyzed. • The pros and cons of ClO 2 -based treatments are evaluated. • Challenges and perspectives for future development are proposed. [ABSTRACT FROM AUTHOR]

Iodinated trihalomethanes (I-THMs) have drawn increasing concerns due to their higher toxicity than those of their chlorinated and brominated analogues. In this study, I-THM formation was firstly evaluated for three treatment scenarios - (i) chlorine alone, (ii) chloramine alone, and (iii) mixed chlorine/chloramine - in the presence and absence of UV irradiation for the iodide-containing humic acid solution or natural water. The results indicated that I-THM formation decreased in the order of mixed chlorination/chloramination > chloramination > > chlorination, which fitted the trend of toxicity evaluation results using Chinese hamster ovary cells. Conversely, total organic halide concentration decreased in the order of chlorination > > chloramination ≈ mixed chlorination/chloramination. Besides, I-THM formation can be efficiently controlled in a UV-activated mixed chlorine/chloramine system. Influencing factors including pH values and Br-/I- molar ratios were also systematically investigated in a mixed chlorine/chloramine system. Enhanced I-THM formation was observed with increasing pH values (6.0–8.0) and Br-/I- molar ratios (1: 1–10: 1). The results obtained in this study can provide new insights into the increasing risk of I-THM formation in a mixed chlorine/chloramine system and the effective control of I-THMs in the iodide-containing water using UV irradiation. [Display omitted] • I-THM concentration decreased in the processes of mixed chlorine/chloramine > chloramine >> chlorine. • UV irradiation exerted efficient control of I-THM formation in a mixed chlorine/chloramine system. • TOX and CHO cell toxicity can be significantly reduced in a UV-activated mixed chlorine/chloramine system. • Both pH values and Br-/I- molar ratios presented vital influence on I-THM formation in a mixed chlorine/chloramine system. [ABSTRACT FROM AUTHOR]

Paraquat (PQ) is the most widely used herbicide in agriculture worldwide and has been considered a high-risk environmental factor for Parkinson's disease (PD). Chronic PQ exposure selectively induces dopaminergic neuron loss, the hallmark pathologic feature of PD, resulting in Parkinson-like movement disorders. However, the underlying mechanisms remain unclear. Here, we demonstrated that repetitive PQ exposure caused dopaminergic neuron loss, dopamine deficiency and motor deficits dose-dependently in mice. Accordingly, mitochondrial calcium uniporter (MCU) was highly expressed in PQ-exposed mice and neuronal cells. Importantly, MCU knockout (KO) effectively rescued PQ-induced dopaminergic neuron loss and motor deficits in mice. Genetic and pharmacological inhibition of MCU alleviated PQ-induced mitochondrial dysfunction and neuronal death in vitro. Mechanistically, PQ exposure triggered mitochondrial fragmentation via imbalance of the optic atrophy 1 (OPA1) processing manifested by cleavage of L -OPA1 to S-OPA1, which was reversed by inhibition of MCU. Notably, the upregulation of MCU was mediated by miR-129–1–3p posttranscriptionally, and overexpression of miR-129–1–3p could rebalance OPA1 processing and attenuate mitochondrial dysfunction and neuronal death induced by PQ exposure. Consequently, our work uncovers an essential role of MCU and a novel molecular mechanism, miR-MCU-OPA1, in PQ-induced pathogenesis of PD, providing a potential target and strategy for environmental neurotoxins-induced PD treatment. [Display omitted] • The pivotal role of MCU is firstly found in PQ-induced neuropathology linked to PD. • MCU indirectly regulates OPA1 processing to orchestrate mitochondrial dynamics and determine the fate of dopaminergic neuron. • miR-129–1-3p is identified to mediate MCU at posttranscriptional level. • Inhibition of MCU may be a potential strategy for environmental neurotoxins-induced PD treatment. [ABSTRACT FROM AUTHOR]

It is highly attractive to develop highly efficient oil-in-water (O/W) emulsion separation technologies for promoting the oily wastewater treatment. Herein, a novel inversely Stenocara beetle -like hierarchical structure of superhydrophobic SiO 2 nanoparticle-decorated CuC 2 O 4 nanosheet arrays were prepared on copper mesh membrane by bridging polydopamine (PDA) to make a SiO 2 /PDA@CuC 2 O 4 membrane for substantially enhanced separation of O/W emulsions. The superhydrophobic SiO 2 particles on the as-prepared SiO 2 /PDA@CuC 2 O 4 membranes were served as localized active sites to induce coalescence of small-size oil droplets in oil-in-water (O/W) emulsions. Such innovated membrane delivered outstanding demulsification ability of O/W emulsion with a high separation flux of 2.5 kL⋅m−2⋅h−1 and its filtrate's chemical oxygen demand (COD) being 30 and 100 mg⋅L−1 for surfactant-free emulsion (SFE) and surfactant-stabilized emulsion (SSE), respectively, and also exhibited a good anti-fouling performance in cycling tests. The innovative design strategy developed in this work broadens the application of superwetting materials for oil-water separation and presents a promising prospect in practical oily wastewater treatment applications. [Display omitted] • A novel inverse Stenocara beetle -like hierarchical structure SiO 2 /PDA@CuC 2 O 4 membrane was fabricated. • Superhydrophobic SiO 2 nanoparticles were bridged by polydopamine to decorate CuC 2 O 4 nanosheets. • The superoleophilic SiO 2 was proven to induce oil droplet coalescence to achieve rapid demulsification. • Such SiO 2 /PDA@CuC 2 O 4 membrane delivered superior separation efficiency of surfactant-stabilized O/W emulsion. • The postulated capture mechanism of oil droplets on the SiO 2 /PDA@CuC 2 O 4 was proposed. [ABSTRACT FROM AUTHOR]

Dealing with arsenic pollution has been of great concern owing to inherent toxicity of As(III) to environments and human health. Herein, a novel multilayered SnO 2 /PPy/ β -PbO 2 structure on TiO 2 nanotube arrays (TNAs/SnO 2 /PPy/ β -PbO 2) was synthesized by a multi-step electrodeposition process as an efficient electrocatalyst for As(III) oxidation in aqueous solution. Such TNAs/SnO 2 /PPy/ β -PbO 2 electrode exhibited a higher charge transfer, tolerable stability, and high oxygen evolution potential (OEP). The intriguing structure with a SnO 2 , PPy, and β -PbO 2 active layers provided a larger electrochemical active area for electrocatalytic As(III) oxidation. The as-synthesized TNAs/SnO 2 /PPy/ β -PbO 2 anode achieved drastically enhanced As(Ⅲ) conversion efficiency of 90.72% compared to that of TNAs/ β -PbO 2 at circa 45.4%. The active species involved in the electrocatalytic oxidation process included superoxide radical (•O 2 −), sulfuric acid root radicals (•SO 4 −), and hydroxyl radicals (•OH). This work offers a new strategy to construct a high-efficiency electrode to meet the requirements of favorable electrocatalytic oxidation properties, good stability, and high electrocatalytic activity for As(III) transformation to As(V). [Display omitted] • Multilayered TNAs/SnO 2 /PPy/ β -PbO 2 anode was fabricated by multi-step electrodeposition. • Such intriguing structures offered a larger electrocatalytic active area for As(III). • Such anode exhibited fast charge transfer, high stability and enhanced OEP. • Such anode delivered a superior electrocatalytic oxidation rate of As(III) at 90.72%. • Electrocatalytic oxidation mechanism of As(III) was ascribed to synergistic effect of·OH,·O 2 −, and·SO 4 −. [ABSTRACT FROM AUTHOR]

Hexavalent chromium in soda ash Chromite Ore Processing Residue (COPR) is harmful to the environment, it is imperative to develop a low cost, efficient, and effective treatment. Herein, a new method (ball milling + sodium sulfide) was developed for mechanochemical treatment of water-leached COPR (W-COPR, about 900 mg/kg non-exchangeble Cr(VI) and mostly chromite bounded). Under a stoichiometric ratio of S2- to Cr(VI) of 5, milling speed of 200 rpm, milling time of 30 min, ball-to-powder weight ratios of 8.5, and, a total Cr(VI) of 76.88 mg/kg and a Toxicity Characteristic Leaching Procedure (TCLP) total Cr value of 1.15 mg/L were achieved after treatment. Results of the mineral liberation analyser (MLA) analyses showed 10% increase of chromite grains liberation and grain size reduction were beneficial to the chromite-bound Cr(VI) reduction. Similar effects were also observed on magnesioferrite encapsulated Cr(VI). Particle aggregation and formation of glass phase colloid precipitation could potentially impede Cr(VI) reduction. Results of X-ray absorption near edge structure (XANES) analyses indicated that the treatment method reduced the actual Cr(VI) concentration to 312 mg/kg with Cr(VI) reduction efficiency of 98% being achieved. Overall, the new method is simple and efficient, and provides a guidance for future industrial application. [Display omitted] • The newly developed method (ball milling + sodium sulfide) is efficient on soda ash COPR treatment. • Chromite liberation and size reduction promote the treatment of the chromite-bound Cr(VI). • Particle aggregation and glass phase formation may potentially impede Cr(VI) reduction. • The XANES analyses indicate that mechanochemical treatment can be further optimized. [ABSTRACT FROM AUTHOR]

A novel application, including mechanochemical pre-treating and alkali leaching, for arsenic selective leaching from copper smelter flue dusts (CSFUs) was developed to overcome the disadvantages of hydrometallurgical methods. Compared with raw CSFU powders, the mechanical-activated ones showed higher maximum arsenic leaching efficiency (increased by ~20%), and lower apparent activation energy (decreased by ~7 kJ·mol−1). Furthermore, this novel process only consumed half of alkali and sulfides and needed one-third of the leaching time to compare with the ones used in the traditional alkali leaching process. The promoting effect of mechanical force on arsenic leaching firstly relied on the physical property changes of CSFU powders, including a decrease of particle sizes and an increase of the specific surface. Secondly, mechanochemical force converted As5+ species into reduced phases (e.g. As 2 O 3 , NaAsO 2), and thio-arsenates (e.g. AsO 2 S 2 3−, AsO 3 S3−), which could spur its leaching due to their stronger mobilities in the alkali solution within sulfides. Finally, mechanochemical activation could be facilitated to separate discrete soluble arsenic species or incorporated ones from sulfate minerals in the CSFUs. This work may have important implications for the development of new eco-friendly technologies for purifying arsenic-bearing materials. [Display omitted] • Mechanochemical pre-treating activates ~20% un-leachable arsenic phases in CSFUs. • Mechanochemical processing saves materials and time for leaching. • Mechanical conversion produces more freely soluble arsenic species. • Decomposing of sulfate cakes promotes arsenic releasing. [ABSTRACT FROM AUTHOR]