Per- and polyfluoroalkyl substances (PFAS) have garnered increasing attention from regulatory authorities and the public because of their widespread presence in global water systems. However, data on PFAS in the aquatic environment of northwestern China, including Ningxia, are scarce. Surface water, sediment, and groundwater samples were analyzed to investigate the occurrence, spatiotemporal distribution, source apportionment, and human health risks associated with PFAS in the water environment of this region. In surface water, concentrations of the 19 PFAS ranged from 3.28 to 234.86 ng/L in the dry season and from 1.31 to 54.55 ng/L in the wet season. Eight PFAS were detected in the sediment and 17 in the groundwater. Their total concentrations ranged from Not Detected (ND) to 7.001 ng/g in sediment and from ND to 34.17 ng/L in groundwater. Positive Matrix Factorization analysis indicated that wastewater discharges from textile mills and other fluorine-containing manufacturers may be the primary source of PFAS in both surface and groundwater. The data from the human health risk assessment indicated that perfluorodecanoic acid, perfluorooctanoic acid, and perfluorooctane sulfonate have significant adverse effects on human health in Ningxia, according to the latest health advisory issued by the Environmental Protection Agency.

Arsenic (As) contamination in agricultural soils endangers environmental health and food security by inducing phytotoxicity, disrupting nutrient balance, and impairing essential physiological functions in crops. A good and long-lasting method of reducing the negative effects of arsenic on plants is to use biofertilizers, which are microbial combinations that aid in plant growth and nutrient movement. This work describes new developments in the use of microbial biofertilizers, namely nitrogen-fixing rhizobia and bacteria that solubilize phosphate, sulfur, and zinc, to remove arsenic (As) from agricultural environments. These methods rely on microbial enzymes, including glutathione S-transferases, catalase, arsenate reductase (ArsC), and arsenite oxidase (AioA). Utilizing biofertilizers in conjunction with organic transporters such as biochar increases the activity of soil enzymes (urease, dehydrogenase), increases the soil’s capacity to retain As (from 21.4 to 35.9 mg/g), and reduces the accumulated As in edible tissues by 10.8% to 55.5%. In addition to increasing the amount of chlorophyll and the activities of antioxidant enzymes (SOD, CAT), the use of plant growth-promoting rhizobacteria (PGPR) with inorganic nanoparticles (ZnO, Fe₃O₄) decreased the movement of As by up to 30.3% in important vegetable crops such as chili pepper (Capsicum annuum), ridge gourd (Luffa acutangula), and pumpkin (Cucurbita moschata). Beyond improving nutrient solubilization, these microbial–nanoparticle consortia also activate systemic resistance pathways, strengthen glutathione-mediated chelation, and remodel root architecture to further limit As uptake. Despite these promising outcomes, scalable field application remains challenged by strain-specific efficacy, formulation stability across variable soils, and a paucity of integrated multi-omics studies.

Rare Earth Metals (REMs) are vital for advanced technologies, yet they face increasing supply risks, emphasising the need for efficient recovery from secondary resources such as NdFeB magnet waste. The present work details the development and characterisation of magnetically responsive vermiculite-based nanocomposites, with and without alginate immobilisation, aimed at the selective recovery of neodymium (Nd(III)) and dysprosium (Dy(III)) ions from synthetic solutions and real NdFeB magnet leachate. The composites were synthesised by incorporating Fe₃O₄ nanoparticles into vermiculite, and, in some cases, the resulting material was encapsulated in alginate beads. X-ray diffraction was utilised to confirm the formation of magnetite, while the magnetic responsiveness of all sorbents was sufficient for straightforward separation. The presence of additional functional groups, including hydroxyl, carboxyl, and silicate, was shown to enhance sorption performance. Although alginate immobilization significantly reduced sorption kinetics, it led to higher sorption capacities and enhanced structural stability. Non-immobilised materials exhibited greater selectivity for Nd(III) over Dy(III), a critical challenge in the separation of REMs. Regeneration studies confirmed the efficient metals desorption when complexing agents were utilised. The high sorption performance of these low-cost and eco-friendly nanocomposites in real leachate systems demonstrates their applicability for sustainable REM recovery from e-waste streams.

The growing demand for biodegradable polymers as sustainable alternatives to conventional plastics underscores the need for effective tools to monitor their environmental dispersion. Detecting bioplastics through remote sensing techniques poses a challenge because, unlike conventional plastics, bioplastics can undergo environmental degradation, potentially altering their spectral signatures and limiting their detectability. A laboratory experiment was conducted to assess the applicability of spectroradiometric techniques for identifying and distinguishing these materials under natural conditions. Two commercial polylactic acid (PLA)-based materials were subjected to pseudo-marine degradation conditions, and their spectral signatures were recorded throughout the degradation period. Infrared (IR) characterisation highlighted differences in the polymeric structure of the two materials. These peculiarities were detected through spectroradiometric analyses that successfully distinguished and characterised the two commercial products after 6 months of exposure to degradation conditions. This study demonstrates that spectroradiometry provides a reliable, cost-effective method for monitoring and distinguishing between various plastic and bioplastic types, supporting waste management and environmental monitoring efforts.

This study developed a monolithic Co₃S₄/FeOOH nanoflower(NF)-like catalyst through impregnation-boiling and mild hydrothermal methods (120 °C, 3 h), overcoming the drawbacks of both conventional ex-situ loading techniques (uneven distribution) and powdered catalysts (difficult separation). The in-situ grown nanoflower-like Co₃S₄/FeOOH composite on NF demonstrated superior peroxymonosulfate (PMS) activation, achieving 87.74% norfloxacin (NOR) removal under optimized conditions (1 cm² catalyst loading with 0.2 g CoCl₂·6H₂O precursor, 0.3 g/L PMS dose, initial pH 6.3), representing around 11-fold and 1.8-fold higher degradation rates than single-component FeOOH/NF and Co₃S₄/NF, respectively. Mechanistic insights of such performance enhancement revealed by electrochemical analysis and Density functional theory (DFT) calculations. Quenching experiments and Electron paramagnetic resonance (EPR) analysis confirmed the coexistence of synergistic pathways involving radical species (SO₄^•−) and non-radical processes (¹O₂ and electron transfer). The Co₃S₄/FeOOH/NF & PMS system retains 84.73% NOR degradation after 3 cycles with stable morphology, while achieving broad-spectrum antibiotic removal (83.69%–99.88%). Fluorescence analysis confirms almost complete mineralization of recalcitrant humic substances from the real hospital wastewater within 40 min.

Ultrafine particles (UFPs), defined as aerosols smaller than 100 nm, are numerically dominant in the atmosphere and play a crucial role in the production of cloud condensation nuclei (CCN). They arise from both new particle formation (NPF) and subsequent growth, as well as from primary emissions such as combustion sources. Despite contributing negligibly to particulate mass, they have disproportionate effects on cloud microphysics and radiative forcing, making them important yet highly uncertain components of the climate system. Current knowledge of how UFPs influence climate points to two primary mechanisms: direct radiative effects, primarily through absorption by black carbon (BC)-containing UFPs, and indirect effects, through their contribution to CCN and subsequent modification of cloud properties. However, substantial knowledge gaps remain. Observations are limited by the low sensitivity of current instrumentation and satellite retrievals, leading to systematic underestimation of UFP abundance and uncertainties in constraining their optical properties. Moreover, large discrepancies persist between observations and model simulations of NPF survival and CCN activation, compounded by the coarse resolution and simplified parameterizations of global models. This perspective emphasizes the need for coordinated multiplatform observations, mechanistic process studies, and the development of cross-scale modeling frameworks. Addressing these challenges will advance the quantitative understanding of UFP-cloud-climate interactions and provide more robust assessments of their role in anthropogenic climate forcing.

Remediation of PAH-contaminated soils is often limited by oxygen delivery, highlighting the importance of organisms that maintain PAH degradation under anoxic conditions. We isolated three Pseudomonas/Stutzerimonas strains on pyrene with nitrate as electron acceptor and confirmed their rapid nitrate-reducing removal of phenanthrene (up to ~90% in 4 d) and benzo[a]pyrene (up to ~95% in 5 d), expanding pure-culture evidence for high-molecular-weight PAH degradation under nitrate respiration. Combined with six previously reported facultative anaerobic PAH-degrading Pseudomonas strains, we analyzed nine genomes representing the presently verifiable phenotype-defined subset. Comparative genomics showed an accessory-dominated pan-genome with a strict core (0.07% of 30101 orthogroups), coexistence of diverse aerobic ring-hydroxylation and anaerobic-associated activation (including carboxylation- and methylation- related) genes. Notably, stress resistance genes were present at significantly elevated copy numbers compared to other genes, reflecting adaptive genomic plasticity. The finding that Pseudomonas was the only genus consistently detected across all 17 petroleum-contaminated soils aligns well with the metabolic flexibility and stress-tolerance potential revealed by our phenotypic and genomic analyses. These findings provide a genomic and ecological framework for understanding facultative anaerobic PAH-degrading Pseudomonas strains and support their application in complex, contaminated environments.

Crustacean shell waste (CSW), generated annually at approximately 11.9 million tons, is predominantly managed through landfilling and incineration. This linear disposal imposes environmental burdens while undervaluing a renewable resource rich in chitin, proteins, and calcium carbonate. Current industrial chitin and chitosan production relies on energy- and chemical- intensive processes, suffers from inconsistent product quality, and recovers only a small fraction of the theoretical potential. This opinion advocates biological valorization, via microbial fermentation and enzymatic offers a technically feasible and environmentally superior alternative for sustainable chitin extraction and conversion. We analyze feasible biotransformation routes, key enabling technologies, and the bottlenecks limiting scale-up, and we highlight a paradigm shift from merely extracting chitin to using it as a fermentable, nitrogen-rich platform substrate for producing high-value chemicals. Integrating synthetic biology, bioprocess engineering, and lifecycle assessment could reposition CSW as a cornerstone feedstock of a sustainable bioeconomy. Such a transition not only addresses waste management challenges but also aligns marine byproduct utilization with circular economy principles and climate mitigation goals.

In order to clarify the health risk of volatile organic compounds (VOCs) emitted during the initial degradation of kitchen waste, a one-year-long sampling campaign was conducted followed by VOCs emission monitoring from kitchen waste bins in a residential area. A total of 40 VOCs with non-carcinogenic risk were identified and 16 of them also had carcinogenic risk. The annual cumulative hazard index was 8.69 ± 20.35 with a median of 2.18 and the annual cumulative carcinogenic risk was (3.91 ± 7.73) × 10^–5 with a median of 1.85 × 10^–5. The highest cumulative hazard index was observed in summer (30.6), significantly exceeding the safety threshold and much higher than that in the other three seasons. Daily variation revealed that, the peaks for both non-carcinogenic and carcinogenic risks appeared at the initial 6 h in summer and at 18–24 h in autumn and winter, but that in spring showed a different pattern. Combined with the detection frequencies of the substances, n-pentane was identified as the key non-carcinogenic risk compound and chloroform as the key carcinogenic risk species. The shortest time periods for the residents to reach the cumulative non-carcinogenic and carcinogenic risk thresholds were approximately 18 and 10 yr, respectively, indicating that the health risks of the VOCs from the kitchen waste bins were relatively low, but a proper attention should be paid to the crucial compounds. This study provides a theoretical basis for risk control and policy implementation in municipal solid waste management.

A numerical model is developed to simulate the photocatalytic degradation of trichloramine (NCl₃) in an annular reactor exposed to artificial or solar irradiation. The approach combines two complementary aspects: 1) a Monte Carlo-based radiative transfer simulation to calculate the angular distribution of irradiance absorbed by the catalyst, and 2) a kinetic framework taking into account mass transport and surface reaction mechanisms, with the reaction rate following Langmuir-Hinshelwood kinetics. The model is first compared with experimental results, obtained with artificial or natural light, and shows good agreement despite local deviations. It is then used to evaluate the spatial distribution of trichloramine decomposition in the reactor, highlighting the complex interaction between heterogeneity of illumination on the reactor and chemical kinetics. The simulation reveals that the boundary regime—controlled by either diffusion or kinetics—varies both radially and angularly, depending on the light available locally. This modeling also enables predictive analysis of operational parameters, including the effects of initial concentration, incident irradiance, and reflector configuration. It provides a basis for analyzing the behavior of photocatalytic reactors and for future optimization of operating conditions and reactor configurations. Beyond trichloramine, the methodology demonstrates the relevance of coupled light–reaction models to guide the development of efficient photocatalytic reactors for air treatment applications.

In this work, we aim at the successful development of a Z-scheme Bi₇O₉I₃/g-C₃N₄/ZnO ternary heterojunction. The synthesised heterojunction photocatalysts were found to be capable of degrading over 99.13% of methyl orange (MO) within 60 min of visible light exposure under optimized reaction parameters. Furthermore, the photocatalyst demonstrated significant stability and maintained its photocatalytic efficacy during four experimental cycles. This heterojunction made it easier for the photo-generated electrons to move and separate at the interfaces of the semiconductors. Bi₇O₉I₃/g-C₃N₄/ZnO heterojunctions outperformed Bi₇O₉I₃, ZnO, and g-C₃N₄ in terms of visible-region photocatalytic performance due to the formation of a Z-scheme heterojunction. Furthermore, the Bi₇O₉I₃/g-C₃N₄/ZnO exhibited an inhibition zone of 25 mm and 28 mm against Escherichia coli and Staphylococcus aureus. The minimum inhibitory concentration (MIC) of 15.62 and 62.5 μg/mL against E. coli and S. aureus. According to these findings, the Bi₇O₉I₃/g-C₃N₄/ZnO heterojunction is a great photocatalyst for organic pollutant degradation when exposed to visible light, and it also demonstrates the potential of antibacterial properties against S. aureus and E. coli.