Environmental impacts of carbon fiber production and decarbonization performance in wind turbine blades.

The application of carbon fiber in the wind power industry is of great interest in declining CO2 emissions but the carbon fiber manufacturing process is still a long way heading cleaner production. Since little to no information clarifies the dual effects from carbon fiber production to application, this study carried out a life cycle assessment (LCA) to recognize the environmental performances of polyacrylonitrile (PAN)-based carbon fiber production and explore the decarbonization effects of carbon fiber application in wind turbine blades. Based on on-site data from a leading carbon fiber production chain in China, potential environmental impacts of carbon fiber production predominantly originated from the precursor spinning stage (accounted for 13-91%). Fossil depletion (20.24 kg oil eq.), climate change (67.79 kg CO2 eq.), terrestrial ecotoxicity (165.63 kg 1,4-DCB eq.) and photochemical ozone formation (0.14 kg NOx eq.) were the four noteworthy areas to improve the sustainable development. Different scenarios in energy and advanced technology were set to explore the potential improvement of the environmental performance of carbon fiber products. Energy structure (wind power) can improve an average of 22.58% environmental benefit compared with the background scenarios. Regarding the decarbonization effects, the energy payback time and the carbon payback time were estimated to be 0.73 and 0.37 months respectively. Therefore, carbon fiber is a trustworthy material in the strategy to achieve sustainable development from a life cycle perspective.

Short- and medium-chain chlorinated paraffins in agricultural and industrial soils from Shanghai, China: surface and vertical distribution, penetration behavior, and health risk assessment.

The widespread contamination of chlorinated paraffins (CPs) of the soil environment has raised global concern due to their highly persistent and toxic properties. However, little information is available regarding these industrial toxicants' spatial-vertical distribution and penetration potentials. In this study, short- and medium-chain chlorinated paraffins (SCCPs and MCCPs, respectively) were analyzed in pooled surface and core soils (0-45 cm) samples collected from agricultural and industrial areas in Shanghai. ∑SCCP concentrations in agricultural and industrial surface soils ranged from 52.6 to 237.6 and 98.3 to 977.1 ng/g dry weight (dw), respectively. ∑MCCP levels were comparatively higher and ranged from 417.2 to 1690.8 and 370.9 to 10,712.7 ng/g dw in agricultural and industrial soils, respectively. C10Cl5-10 SCCPs and C14-15Cl5-7 MCCPs were the predominant homologues in all samples. Analysis of the soil vertical profiles revealed that MCCP concentrations decreased significantly with depth (P < 0.01). SCCPs more efficiently penetrated into the soils than MCCPs because of their higher water solubility and less octanol-water partition coefficient (Kow) values. A preliminary risk assessment suggested no potential health risks caused by non-dietary exposure. The daily exposure doses of CPs via ingestion were significantly (P < 0.01) higher for children (5.41 ± 2.11 × 10-3 and 1.68 ± 1.03 × 10-2 µg kg-1 day-1) and adults (2.56 ± 0.99 × 10-4 and 7.94 ± 4.87 × 10-4 µg kg-1 day-1) than dermal permeation exposure. Furthermore, CPs at current levels posed low ecological risks (0.1 ≤ RQ < 1) according to the risk quotient model. This study enhanced our understanding of the fates and behaviors of CPs in the terrestrial environment.

Carbon nanotube filter functionalized with MIL-101(Fe) for enhanced flow-through electro-Fenton.

Herein, an electrochemical carbon nanotubes (CNT) filter modified with MIL-101(Fe) has been designed for the electro-Fenton applications by serving as a functional flow-through electrode. Under an electric field, the hybrid filter enabled the in situ generation of H2O2via the two-electron oxygen reduction reaction, which promoted the production of HO by the accelerated Fe2+/Fe3+ cycling of MIL-101(Fe). It was observed that 93.2 ± 1.2% tetracycline and 69.0 ± 0.8% total organic carbon (TOC) were removed in 2 h under the optimized conditions. The electron paramagnetic resonance (EPR) analysis and radical scavenging experiments revealed that HO predominated the tetracycline degradation. As compared to the batch reactor, the performance of the proposed system was improved by 5.6 times owing to the convection-enhanced mass transport. The plausible working mechanism and degradation pathway were also subsequently proposed. The findings reported in this study provide a promising insight for the environmental remediation by integrating nanotechnology and Fenton chemistry.

Spatio-vertical distribution of riverine microplastics: Impact of the textile industry.

Microplastics (MPs) contamination in rivers and lakes is of paramount environmental importance as freshwater systems transport MPs from land to ocean. However, information regarding the spatio-vertical distributions of MPs in rivers, and their associations with surrounding industrial activities, is scarce and unclear. This study investigated MPs in the Taipu River, where there is a highly developed textile industry in Yangtze River Delta, China. Results showed a widespread occurrence of MPs particles with concentrations in the range of 0.65-6.07 items/L and 0.30-3.63 items/L in surface and bottom waters. A higher abundance of MPs was observed in surface waters than in bottom waters (t = 5.423, p = 0.024). The MPs distributions varied markedly in space, with the highest abundances being found in textile manufacturing zones as a consequence of industrial release (F = 14.642, p < 0.001). Transparent fibers were the major MPs compositions with 100-500 µm in size. Polyethylene terephthalate (PET) accounted for 71.4% and 59.73% of the total MPs identified in surface and bottom water, respectively. These PET polymers were predominantly presented in "fibrous" shapes, further reflecting the point sources of textile wastewater. Moreover, polyvinyl acetate (PVAC), used as fabric coating and resin matrix to form nonwoven fabrics, was firstly highlighted at a watershed scale. Although risk assessments revealed a light to moderate risks of MPs in the Taipu River, textile wastewater appears to cause a high "grey water" footprint and increase the risks of MPs pollution from textile life-cycle production. This study bridged gaps between field data and policy-making for MPs control and shed insight into the cleaner production of the textile industry.

Defect-Rich Hierarchical Porous UiO-66(Zr) for Tunable Phosphate Removal.

The introduction of defects into hierarchical porous metal-organic frameworks (HP-MOFs) is of vital significance to boost their adsorption performance. Herein, an advanced template-assisted strategy has been developed to fine-tune the phosphate adsorption performance of HP-MOFs by dictating the type and number of defects in HP-UiO-66(Zr). To achieve this, monocarboxylic acids of varying chain lengths have been employed as template molecules to fabricate an array of defect-rich HP-UiO-66(Zr) derivatives following removal of the template. The as-prepared HP-UiO-66(Zr) exhibits a higher sorption capacity and faster sorption rate compared to the pristine UiO-66(Zr). Particularly, the octanoic acid-modulated UiO-66(Zr) exhibits a high adsorption capacity of 186.6 mg P/g and an intraparticle diffusion rate of 6.19 mg/g·min0.5, which are 4.8 times and 1.9 times higher than those of pristine UiO-66(Zr), respectively. The results reveal that defect sites play a critical role in boosting the phosphate uptake performance, which is further confirmed by various advanced characterizations. Density functional theory (DFT) calculations reveal the important role of defects in not only providing additional sorption sites but also reducing the sorption energy between HP-UiO-66(Zr) and phosphate. In addition, the hierarchical pores in HP-UiO-66(Zr) can accelerate the phosphate diffusion toward the active sorption sites. This work presents a promising route to tailor the adsorption performance of MOF-based adsorbents via defect engineering.

Silicate-Enhanced Heterogeneous Flow-Through Electro-Fenton System Using Iron Oxides under Nanoconfinement.

Herein, a silicate-enhanced flow-through electro-Fenton system with a nanoconfined catalyst was rationally designed and demonstrated for the highly efficient, rapid, and selective degradation of antibiotic tetracycline. The key active component of this system is the Fe2O3 nanoparticle filled carbon nanotube (Fe2O3-in-CNT) filter. Under an electric field, this composite filter enabled in situ H2O2 generation, which was converted to reactive oxygen species accompanied by the redox cycling of Fe3+/Fe2+. The presence of the silicate electrolyte significantly boosted the H2O2 yield by preventing the O-O bond dissociation of the adsorbed OOH*. Compared with the surface coated Fe2O3 on the CNT (Fe2O3-out-CNT) filter, the Fe2O3-in-CNT filter demonstrated 1.65 times higher kL value toward the degradation of the antibiotic tetracycline. Electron paramagnetic resonance and radical quenching tests synergistically verified that the dominant radical species was the 1O2 or HO· in the confined Fe2O3-in-CNT or unconfined Fe2O3-out-CNT system, respectively. The flow-through configuration offered improved tetracycline degradation kinetics, which was 5.1 times higher (at flow rate of 1.5 mL min-1) than that of a conventional batch reactor. Liquid chromatography-mass spectrometry measurements and theoretical calculations suggested reduced toxicity of fragments of tetracycline formed. This study provides a novel strategy by integrating state-of-the-art material science, Fenton chemistry, and microfiltration technology for environmental remediation.

Supported Atomically-Precise Gold Nanoclusters for Enhanced Flow-through Electro-Fenton.

Gold (Au) has been considered catalytically inert for decades, but recent reports have described the ability of Au nanoparticles to catalyze H2O2 decomposition in the Haber-Weiss cycle. Herein, the design and demonstration of a flow-through electro-Fenton system based on an electrochemical carbon nanotube (CNT) filter functionalized with atomically precise Au nanoclusters (AuNCs) is described. The functionality of the device was then tested for its ability to catalyze antibiotic tetracycline degradation. In the functional filters, the Au core of AuNCs served as a high-performance Fenton catalyst; while the AuNCs ligand shells enabled CNT dispersion in aqueous solution for easy processing. The hybrid filter enabled in situ H2O2 production and catalyzed the subsequent H2O2 decomposition to HO·. The catalytic function of AuNCs lies in their ability to undergo redox cycling of Au+/Au0 under an electric field. The atomically precise AuNCs catalysts demonstrated superior catalytic activity to larger nanoparticles; while the flow-through design provided convection-enhanced mass transport, which yielded a superior performance compared to a conventional batch reactor. The adsorption behavior and decomposition pathway of H2O2 on the filter surfaces were simulated by density functional theory calculations. The research outcomes provided atomic-level mechanistic insights into the Au-mediated Fenton reaction.

The enhanced degradation and detoxification of chlortetracycline by Chlamydomonas reinhardtii.

Nowadays, numerous studies have focused on the newly developed technologies for the thorough removal of tetracyclines (TCs). However, it is often ignored that the parent TCs have limited stability in aquatic environments. Thus, this study selected green alga Chlamydomonas reinhardtii with high chlorophyll content to rapidly degrade chlortetracycline (CTC) into products with low toxicity. As the results shown, the half-life times of CTC (1 × 10-6 mol/L) decreased from 10.35 h to 2.55 h by the presence of C. reinhardtii at 24±1 °C with 12/12 h dark/light cycle. The main transformation products were iso-chlortetracycline (ICTC), 4-epi-iso-chlortetracycline (EICTC), and other degradation products with lower molecular weight. The toxicity evaluation shows that the negative effects of CTC on growth rate and soluble protein content of green algae were significantly alleviated after the enhanced degradation treatment, while the generation of reactive oxygen species (ROS) and antioxidant response in algal cells returned to normal levels. The chlorophyll of algae played an important role of photosensitizer, which catalyzed the photo-induced electron/energy transfer of CTC degradation. The ROS generation of algae also was also inseparable from the enhanced degradation of CTC, especially when the chlorophyll was damaged at the high CTC concentration. Based on these results, we can better select suitable algal species to further strengthen the degradation of antibiotics and effectively reduce the environmental risk of CTC in aqueous system.

Electroactive Modified Carbon Nanotube Filter for Simultaneous Detoxification and Sequestration of Sb(III).

Herein, we rationally designed a dual-functional electroactive filter system for simultaneous detoxification and sequestration of Sb(III). Binder-free and nanoscale TiO2-modified carbon nanotube (CNT) filters were fabricated. Upon application of an external electrical field, in situ transformation of Sb(III) to less toxic Sb(V) can be achieved, which is further sequestered by TiO2. Sb(III) removal kinetics and capacity increase with applied voltage and flow rate. This can be explained by the synergistic effects of the filter's flow-through design, electrochemical reactivity, small pore size, and increased number of exposed sorption sites. STEM characterization confirms that Sb were mainly sequestered by TiO2. XPS, AFS, and XAFS results verify that the Sb(III) conversion process was accelerated by the electrical field. The proposed electroactive filter technology works effectively across a wide pH range. The presence of sulfate, chloride, and carbonate ions negligibly inhibited Sb(III) removal. Exhausted TiO2-CNT filters can be effectively regenerated using NaOH solution. At 2 V, 100 µg/L Sb(III)-spiked tap water generated ∼1600 bed volumes of effluent with >90% efficiency. Density functional theory calculations suggest that the adsorption energy of Sb(III) onto TiO2 increases (from -3.81 eV to -4.18 eV) and Sb(III) becomes more positively charged upon application of an electrical field.

Fe-N-Graphene Wrapped Al2O3/Pentlandite from Microalgae: High Fenton Catalytic Efficiency from Enhanced Fe3+ Reduction.

Efficient cycling of Fe3+/Fe2+ is a key step for the Fenton reaction. In this exploration, from microalgae, we have prepared a novel Fe-N-graphene wrapped Al2O3/pentlandite composite which showed high Fenton catalytic ability through accelerating of Fe3+ reduction. The catalyst exhibits high activity, good reusability along with stability, and wide adaptation for the organics degradation under neutral pH. High TON and H2O2 utilization efficiency have also reached by this catalyst. Characterization results disclose a unique structure that the layered Fe-N-graphene structure tightly covers on Al2O3/pentlandite particles. Mechanistic evidence suggests that the accelerated Fe3+/Fe2+ redox cycle originates from the enhanced electron transfer by the synergistic effect of Fe, Ni and Al in the catalyst, and it causes the low H2O2 consumption and high •OH generation rate. Moreover, organic radicals formed in the Fenton process also participate in the Fe3+ reduction, and this process may be accelerated by the N doped graphene through a quick electron transfer. These findings stimulate an approach with great potential to further extend the synthetic power and versatility of Fenton catalysis through N doped graphene in catalysts.

Iron Plaque: A Barrier Layer to the Uptake and Translocation of Copper Oxide Nanoparticles by Rice Plants.

The waterlogging environment generally results in the deposition of iron plaque on plant roots, which may impact the fate of metal-based nanoparticles. Here, we investigated the influence of iron plaque on the uptake, translocation, and transformation of copper oxide nanoparticles (CuO NPs) in rice plants. The results show that the presence of iron plaque dramatically reduced the Cu contents in roots and shoots by 89% and 78% of those without iron plaque under 100 mg/L CuO NP treatment. Meanwhile, the Cu accumulation in plants was negatively related to the amount of iron plaque. X-ray absorption near edge structure (XANES) analysis demonstrated lower percentage of CuO but higher proportion of Cu(I) in shoots exposed to CuO NPs with the formation of iron plaque. Furthermore, micro X-ray fluorescence (µ-XRF) combined with µ-XANES revealed that the iron plaque in the root epidermis and exodermis consisted of goethite and ferrihydrite, which hindered the uptake of CuO NPs by roots. However, a few CuO NPs were still absorbed by roots via root hairs or lateral roots, and further translocated to shoots. But eventually, more than 90% of total Cu(II) was reduced to Cu(I)-cysteine and Cu2O in leaf veins of rice plants with iron plaque.

Recent advances in anaerobic biological processes for textile printing and dyeing wastewater treatment: a mini-review.

Textile printing and dyeing wastewater is usually characterized by high pH, high turbidity, poor bio-degradability, complex composition, and high chrominance, and is discharged in large amounts. It has been regarded as one of the hardest to treat forms of industrial wastewater. Conventional physicochemical technologies can remove these contaminants from water bodies, but at the expense of high energy consumption and high cost. Alternatively, biological processes with limited energy consumption, low cost and high efficiency are considered as promising technologies. Among them, the anaerobic biological processes have been proven to be effective for the treatment of high-concentration textile printing and dyeing wastewater. In this mini-review, recent advances on high-rate anaerobic technologies for such purposes are reviewed. Current limitations of these technologies are summarized, and future research directions are indicated.

Preparation and properties of chitosan-metal complex: Some factors influencing the adsorption capacity for dyes in aqueous solution.

Chitosan-metal complexes have been widely studied in wastewater treatment, but there are still various factors in complex preparation which are collectively responsible for improving the adsorption capacity need to be further studied. Thus, this study investigates the factors affecting the adsorption ability of chitosan-metal complex adsorbents, including various kinds of metal centers, different metal salts and crosslinking degree. The results show that the chitosan-Fe(III) complex prepared by sulfate salts exhibited the best adsorption efficiency (100%) for various dyes in very short time duration (10min), and its maximum adsorption capacity achieved 349.22mg/g. The anion of the metal salt which was used in preparation played an important role to enhance the adsorption ability of chitosan-metal complex. SO42- ions not only had the effect of crosslinking through electrostatic interaction with amine group of chitosan polymer, but also could facilitate the chelation of metal ions with chitosan polymer during the synthesis process. Additionally, the pH sensitivity and the sensitivity of ionic environment for chitosan-metal complex were analyzed. We hope that these factors affecting the adsorption of the chitosan-metal complex can help not only in optimizing its use but also in designing new chitosan-metal based complexes.

Phthalate degradation by glow discharge plasma enhanced with pyrite in aqueous solution.

In order to prevent health risk from potential exposures to phthalates, a glow discharge plasma (GDP) process was applied for phthalate degradation in aqueous solution. The results revealed that the phthalate derivatives 4-hydroxyphthalic acid, 4-methylphthalic acid and 4-tert-butylphthalic anhydride could be degraded efficiently in GDP process (498 V, 0.2 A) with high removal efficiencies of over 99% in 60 minutes. Additionally, pyrite as a promising heterogeneous iron source in the Fenton reaction was found to be favorable for GDP process. The phthalate degradation reaction could be significantly enhanced by the continuous formation of •OH and the inhibition of the quenching reaction in the pyrite Fenton system due to the constant dissolution of Fe(II) from pyrite surface. Meanwhile, the initial pH value showed little impact on the degradation of phthalates and the energy efficiency of GDP system for phthalate degradation ranged between 0.280 × 10-9 and 1.210 × 10-9 mol/J, which is similar to the GDP system with phenol, bisphenol A and methyl tert-butyl ether as the substrates. Further, the X-ray diffraction and scanning electron microscopy with energy dispersive X-ray spectroscopy analyses indicated that the pyrite was relatively stable in GDP system and there was no obvious polymeric compound formed on the catalyst surface. Overall, this GDP process offers high removal efficiency, simple technology, considerable energy efficiency and the applicability to salt-containing phthalate wastewater.

Stress Responses and Ammonia Nitrogen Removal Efficiency of Oocystis lacustris in Saline Ammonium-Contaminated Wastewater Treatment.

The increasing concern over climate change has spurred significant interest in exploring the potential of microalgae for wastewater treatment. Among the various types of industrial wastewaters, high-salinity NH4+-N wastewater stands out as a common challenge. Investigating microalgae's resilience to NH4+-N under high-salinity conditions and their efficacy in NH4+-N utilization is crucial for advancing industrial wastewater microalgae treatment technologies. This study evaluated the effectiveness of employing nitrogen-efficient microalgae, specifically Oocystis lacustris, for NH4+-N removal from saline wastewater. The results revealed Oocystis lacustris's tolerance to a Na2SO4 concentration of 5 g/L. When the Na2SO4 concentration reached 10 g/L, the growth inhibition experienced by Oocystis lacustris began to decrease on the 6th day of cultivation, with significant alleviation observed by the 7th day. Additionally, the toxic mechanism of saline NH4+-N wastewater on Oocystis lacustris was analyzed through various parameters, including chlorophyll-a, soluble protein, oxidative stress indicators, key nitrogen metabolism enzymes, and microscopic observations of algal cells. The results demonstrated that when the Oocystis lacustris was in the stationary growth phase with an initial density of 2 × 107 cells/L, NH4+-N concentrations of 1, 5, and 10 mg/L achieved almost 100% removal of the microalgae on the 1st, 2nd, and 4th days of treatment, respectively. On the other hand, saline NH4+-N wastewater minimally impacted photosynthesis, protein synthesis, and antioxidant systems within algal cells. Additionally, NH4+-N within the cells was assimilated into glutamic acid through glutamate dehydrogenase-mediated pathways besides the conventional pathway involving NH4+-N conversion into glutamine and assimilation amino acids.

From disinfection to pathogenicity: Occurrence, resistome risks and assembly mechanism of biocide and metal resistance genes in hospital wastewaters.

Hospital wastewaters (HWWs) represent critical reservoir for the accumulation and propagation of resistance genes. However, studies on biocide and metal resistance genes (BMRGs) and their associated resistome risks and driving mechanisms in HWWs are still in their infancy. Here, metagenomic assembly was firstly used to investigate host pathogenicity and transferability profiles of BMGRs in a typical HWWs system. As a result, genes conferring resistance to Ethidium Bromide, Benzylkonium Chloride, and Cetylpyridinium Chloride dominated biocide resistance genes (BRGs), whereas Cu resistance gene was the largest contributor of metal resistance genes (MRGs). Most BMRGs experienced significant reduction from anoxic-aerobic treatment to sedimentation stages but exhibited enrichment after chlorine disinfection. Network analysis indicated intense interactions between BMRGs and virulence factors (VFs). Polar_flagella, belonging to the adherence was identified to play important role in the network. Contig-based analysis further revealed noteworthy shifts in host associations along the treatment processes, with Pseudomonadota emerging as the primary carrier, hosting 91.1% and 85.3% of the BRGs and MRGs. A total of 199 opportunistic pathogens were identified to carry 285 BMRG subtypes, which mainly included Pseudomonas alcaligenes, Pseudomonas lundensis, and Escherichia coli. Notably, ruvB conferring resistance to Cr, Cetylpyridinium Chloride, and Dodine were characterized with the highest frequency carried by pathogens. Diverse co-occurrence patterns between BMRGs and mobile genetic elements (MGEs) were found from the raw influent to final effluent. Overall, 10.5% BRGs and 8.84% MRGs were mobile and among the 4 MGEs, transposase exhibited the greatest potential for the BMRGs dissemination. Furthermore, deterministic processes played a dominant role in bacterial communities and BMRGs assembly in HWWs. Bacterial communities contributed more than MGEs in shaping the resistome. Taken together, this work demonstrated widespread BMRGs pollution throughout the HWWs treatment system, emphasizing the potential for informing resistome risk and ecological mechanism in medical practice.

Cleaner production evaluation system for textile industry: An empirical study from LCA perspectives.

The contradiction between the rapid textile expansion and intensive energy consumption, highly environmental pollution calls for the adoption of cleaner production (CP). However, current evaluation system mainly targeted on CP at production stage, guidance and support on the life cycle assessment is still in its infancy. Meanwhile few studies brought the combination of water conservation and carbon reduction into considerations. This study compared the existing CP evaluation systems including guidelines for the whole industry, standards for textile industry and indicators for the dyeing and finishing sector by quantifying the differences of indicator score compositions. Comparisons analysis from six aspects suggested that all the evaluation systems had relevant indicators regarding "pollutant emissions". "Management", "process equipment and techniques" and "resource and energy consumption" have also been well concerned while "product characteristic" seemed to be overlooked at current stage. From the perspective of whole life cycle, the key of textile processing is the "printing and dyeing" (44.23 %) followed by "fabric manufacturing"(28.85 %) and setting (15.38 %). With regards to the environmental impacts, resources depletion gained the highest attention since their indicator scores reached up to 25.71 %, 18.47 % and 20.62 % for EMAS, ERG 2018 and HJ-1852006. Cleaner production awareness and social impact also played significant roles in ISO 14031:2021 and WMG. Subsequently, a set of new comprehensive CP evaluation indicator system was established, including 3 scopes and 7 goals. The newly-built indicator system incorporated with life cycle perspectives gave a powerful tool to measure the CP level in textile industry and of CP will benefit from water reuse and energy utilization with high efficiency.

Spatial distribution, isomer signature and air-soil exchange of legacy and emerging poly- and perfluoroalkyl substances.

Widespread occurrences of various poly- and perfluoroalkyl substances (PFAS) in terrestrial environment calls for the growing interest in their transport behaviors. However, limited studies detected PFAS with structural diversity in tree barks, which reflect the long-term contamination in atmosphere and play a vital role in air-soil exchange behaviors. In this study, 26 PFAS congeners and typical branched isomers were investigated in surface soils and tree barks at 28 sites along the Taihu Lake, Taipu River, and Huangpu River. Concentrations of total PFAS in soils and tree barks were 0.991-29.4 and 7.99-188 ng/g dw, with PFPeA and PFDoA were the largest contributors in the two matrices. The highest PFAS levels were found in the Taihu Lake watershed, where textile manufacturing and metal plating activities highly prosper. With regard to the congener and isomer signatures, short-chain homologs dominated in soils (65.5%), whereas long-chain PFAS showed a major proportion in barks (41.9%). The composition of linear isomers of PFOS, PFOA and PFHxS implied that precursor degradation might be an important source of PFAS in addition to the 3M electrochemical fluorination (ECF). Additionally, the distance from the emission source, total organic carbon (TOC), logKOA and logKOW were considered potential influencing factors in PFAS distributions. Based on the multi-media fugacity model, about 71% of the fugacity fraction (ffs) values of the PFAS were below 0.3, indicating the dominant deposition from the atmosphere to the soil. The average fluxes of air-soil exchange for PFAS were -0.700 ± 11.0 ng/(m2·h). Notably, the estimated daily exposure to PFAS ranged from 9.57 × 10-2 to 8.59 × 10-1 ng/kg·bw/day for children and 3.31 × 10-2 to 3.09 × 10-1 ng/kg·bw/day for adults, suggesting low risks from outdoor inhalation and dermal uptake. Overall, results from distribution with structural diversity, air-soil exchange and preliminary risk assessment. This study provided in-depth insight of PFAS in multi-medium environment and bridged gaps between field data and policy-making for pollution control.

Enhancement of peroxymonosulfate activation for 2,4-dichlorophenoxyacetic acid removal by MoSe2 induced Fe redox cycles.

The limited regeneration of Fe2+ in the Fe-catalyzed advanced oxidation processes (AOPs) constrained its application for the removal of organic pollutants. Herein, MoSe2 was introduced to promote the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) in the Fe2+/PMS system. Compared with Fe2+/PMS processes, the 2,4-D degradation efficiency and PMS decomposition rate respectively increased by 73.8% and 84.2% in the MoSe2/Fe2+/PMS system. DFT simulation results suggested that Se atoms acted smoothly as the bridge supporting the charge transfer from Mo to adjacent Fe atoms, which led to the reduction of Fe3+. The rapid regeneration of Fe2+ boosted the activation of PMS and the degradation of pollutants. Additionally, the electron paramagnetic resonance (EPR) and quenching experiments results indicated that SO4∙-, ∙OH, and 1O2 accounted for 2,4-D degradation, and SO4∙- and 1O2 predominated the reaction. The Mo based co-catalysts showed better co-catalytic effect than the W counterparts, and the moderate adsorption for PMS and lower electron transfer electron transfer resistance accounted for the more excellent co-catalytic performance of MoSe2 than that of WSe2. In addition, the degradation efficiency of 2,4-D was up to 95.5% after five cycles of MoSe2 in the co-catalytic system. The coexistent humic acid (HA) and Cl- showed ignorant negative effect on the degradation, while HCO3- would depress the oxidation reaction. The acidic etching wastewater can be applied as the Fe ions source in this co-catalytic process to remove 2,4-D effectively.

Phytotoxicity alleviation of imazethapyr to non-target plant wheat: active regulation between auxin and DIMBOA.

Effectively controlling target organisms while reducing the adverse effects of pesticides on non-target organisms is a crucial scientific inquiry and challenge in pesticide ecotoxicology research. Here, we studied the alleviation of herbicide (R)-imazethapyr [(R)-IM] to non-target plant wheat by active regulation between auxin and secondary metabolite 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazine-3(4H)-one (DIMBOA). We found (R)-IM reduced 32.4% auxin content in wheat leaves and induced 40.7% DIMBOA accumulation compared to the control group, which effortlessly disrupted the balance between wheat growth and defense. Transcriptomic results indicated that restoration of the auxin level in plants promoted the up-regulation of growth-related genes and the accumulation of DIMBOA up-regulated the expression of defense-related genes. Auxin and DIMBOA alleviated herbicide stress primarily through effects in the two directions of wheat growth and defense, respectively. Additionally, as a common precursor of auxin and DIMBOA, indole adopted a combined growth and defense strategy in response to (R)-IM toxicity, i.e., restoring growth development and enhancing the defense system. Future regulation of auxin and DIMBOA levels in plants may be possible through appropriate methods, thus regulating the plant growth-defense balance under herbicide stress. Our insight into the interference mechanism of herbicides to the plant growth-defense system will facilitate the design of improved strategies for herbicide detoxification.