Microplastics (MPs) in river ecosystems significantly affect sediment microbial communities and biogeochemical cycling. However, the specific microbial responses to distinct MPs and their subsequent effects on greenhouse gas (GHG) emissions remain poorly understood. In this study, the effects of conventional polyvinyl chloride (PVC) and biodegradable polylactic acid (PLA) on sediment microbial communities and GHG emissions were compared. Both PVC and PLA increased sediment total organic carbon (STOC) by 31.3% and 36.7%, respectively, leading to an increase in sediment bacterial abundance. Notably, compared with PLA, PVC reduced bacterial richness more significantly. Community composition and FAPROTAX function prediction analysis revealed that PVC-enriched taxa involved in nitrate reduction (e.g., Desulfuromonas, Hydrogenophage, Azospira) resulted in a significant decrease in NO₃⁻ contents. In contrast, PLA increased the abundance of microorganisms associated with organic matter degradation (Chitinophagaceae, Comamonadaceae, and Caulobacteraceae). Both PVC and PLA significantly reduced the relative abundance of the mcrA gene, leading to decreased CH₄ fluxes, likely due to competition from enriched acetate-utilizing bacteria (Desulfuromonas, Pseudomonas, and Azospira). Additionally, PLA significantly reduced the abundance of the nirK gene. This study systematically elucidates the differential effects of PVC and PLA on microbial community structure and GHG emissions, providing new insights into the ecological impacts of MPs.

This study investigates the use of struviterient-loaded magnesium-modified biochar beads (Ca/MgBC + NP) as a slow-release fertilizer and soil amendment, comparing its performance with commercially available slow-release fertilizers (SRF) in different soils and crop types. The results demonstrate that Ca/MgBC + NP exhibited satisfying swelling, water retention, and slow-release properties in all tested soils. In sandy soil, which showed the most significant differences (p < 0.05), Ca/MgBC + NP enhanced the growth of Brassica chinensis L. and Spinacia oleracea L. after 90 d, with shoot and root lengths, as well as fresh and dry weights, 1.25–2.84 times higher than those treated with SRF. The cation exchange capacity and organic carbon content of sandy soil were significantly improved (by 38.55% and 265.38%), overcoming its natural limitations in water and fertilizer retention. Principal Component Analysis (PCA) confirmed that soil properties played a crucial role in crop growth (52.67% variance explained). Spectroscopic analysis indicated that magnesium-related compounds, including struvite and Mg(PO₄)₃, contributed to the observed growth promotion. Furthermore, Ca/MgBC + NP effectively immobilized heavy metals, particularly Cr and Hg, with immobilization rates exceeding 80%. This study highlights the potential of Ca/MgBC + NP as a sustainable, low-cost fertilizer that not only enhances crop growth but also improves soil health and remediates heavy metal contamination, providing a promising alternative for green agriculture.

Anaerobic digestion (AD) is a commonly used technology for facilitating carbon fixation by converting complex organic matter into volatile fatty acids and CH₄; however, the issue of CO₂ emission remains unresolved in AD. The formation of amorphous carbon has been identified as a more direct method of carbon fixation in AD. This study aimed to elucidate how amorphous carbon can be formed from organic matter or CO₂ by anaerobic microorganisms. The results showed that amorphous carbon was produced in the anaerobic digestion of inorganic and mixed carbon sources, with yields of 0.38 and 3 µg/10⁵ cells, respectively. Its characteristics were analyzed using Raman microscopy. Isotope labeling revealed that CO₂ fixation into amorphous carbon primarily depends on the reversed oxidative tricarboxylic acid cycle (roTCA) and hydroxycaproate. Differential pulse voltammetry combined with gene abundance analysis indicated that flavin electron bifurcation (EB) is involved in electron transfer. The microbial isothermal calorimeter further measured the metabolic calorific value, demonstrating that anaerobic microorganisms can autotrophically fix CO₂ with energy provided by EB. Metagenomic analysis supported the large REDOX equivalents input from EB to sustain the roTCA cycle. This research contributes to understanding the mechanism of CO₂ fixation into solid carbon in anaerobic environments. Additionally, it provides new insights into the potential development of carbon-negative technologies in anaerobic biological treatment.

This study examined particulate matter with a diameter of 2.5 μm or less (PM_2.5) samples to investigate seasonal shifts in bacterial and fungal communities in Seoul, Republic of Korea. To assess these variations and the influence of environmental factors, DNA was extracted from PM_2.5 samples and subjected to sequencing analysis. The results showed distinct seasonal changes in microbial communities. Pseudarthrobacter dominated in winter, Arthrospira in spring, Rhodococcus in summer, and Pelomonas in autumn among the bacterial communities, while Candida in winter, Coprinopsis in spring, and Cutaneotrichosporon in both summer and autumn were prevalent in fungal communities. Bacterial richness peaked in spring, whereas fungal richness was highest in winter. These shifts were driven by environmental factors: air pollutants and chemical compositions had a greater influence in winter and spring, while meteorological conditions, such as temperature and humidity, were dominant in summer and autumn. Functional gene analysis revealed a prevalence of metabolic pathways essential for microbial survival, with fungi showing a higher proportion of saprotrophs, particularly in spring. This comprehensive analysis, considering a wide range of environmental factors including meteorological conditions, air pollutants, and atmospheric organic compounds such as polyaromatic hydrocarbons (PAHs) and dicarboxylic acids (DCAs), provides novel insights into the dynamic relationships between environmental factors and microbial communities in PM_2.5, highlighting the significant role of anthropogenic influences. This research advances our understanding of atmospheric microbial ecosystems and their seasonal dynamics.

The landfill leachate harbors a substantial volume of pollutants necessitating their eradication prior to environmental release. In this investigation, the electrochemical oxidation of Biologically Treated Landfill Leachate (BTLL), following treatment via Upflow Anaerobic Sludge Blanket (UASB). This investigation delved into and compared with the impact of various operational parameters within the electrochemical oxidation process for both Ti/SnO₂-Sb₂O₃ and Ti/PbO₂ anodes—namely, current density, duration of operation, sodium chloride concentration, and cathode—on the efficiency of pollutant removal. Additionally, it employed response surface methodology to discern the optimal operational conditions for electrochemical oxidation of landfill leachate. The final experimental results indicate that under a current density of 50 mA/cm² and an electrolysis time of 4 h, the COD removal rates for Ti/SnO₂-Sb₂O₃ anode and Ti/PbO₂ anode were 79.48% and 92.31%, respectively, while the TN removal rates were 57.99% and 57.17%, respectively. Additionally, NH₄⁺-N was completely removed for Ti/SnO₂-Sb₂O₃ anode and Ti/PbO₂ anode. Moreover, the former exhibited superior sewage treatment effectiveness when Ni was used as the cathode compared to Pt and steel. Response surface methodology (RSM) identified anode-specific optima: Ti/SnO₂-Sb₂O₃ (34 mA/cm², 7.3 g/L NaCl) and Ti/PbO₂ (38 mA/cm², 6.0 g/L NaCl), both at 4 h, yielding COD removals of 93.6% and 97.2% (experimentally validated), respectively. This study provides novel theoretical support for the combined treatment of landfill leachate using biotreatment and chemical oxidation processes.

Ammonia (NH₃) is a key precursor of fine particulate matter (PM_2.5) in the air; however, its emission sources at different heights remain poorly understood in the Pearl River Delta (PRD) region of China. In this study, we simultaneously collected PM_2.5 samples at three atmospheric heights (ground, 118 m, and 488 m) based on the atmospheric observatories of Canton Tower, the tallest structure in the PRD region. Our results showed that the average NH₄⁺ concentrations were 2.7 ± 1.4, 3.0 ± 1.8, and 2.6 ± 1.7 μg/m³ at the ground site, 118 m, and 488 m during the sampling campaign, with no significant difference (p > 0.05) among the three heights. However, the stable nitrogen isotope composition values in NH₄⁺ (δ¹⁵N-NH₄⁺) displayed a significant correlation with height (p < 0.05). We further calculated the initial δ¹⁵N-NH₃ values and performed source apportionments using the Bayesian Isotope Mixture Model. The results indicated that the mean contributions of agriculture, waste, vehicle, biomass burning, NH₃ slip, and coal combustion were 9.9% ± 4.4%, 8.3% ± 5.5%, 29% ± 8.0%, 16% ± 2.2%, 25% ± 6.0%, and 12% ± 3.4%, respectively, at the ground site during the sampling campaign. By contrast, the contributions of sources at 488 m remained relatively stable due to the limited influence of local activities. Overall, our study highlights the dominant role of combustion sources in NH₃ emissions in the PRD region, with their contribution being highly dependent on atmospheric height.

Highly persistent per- and polyfluorinated alkyl substances (PFAS) have been extensively used worldwide for decades and are now ubiquitous in the ecosystem. To combat problems related to PFAS accumulation in the environment and their intrusion into the human body, PFAS adsorption and subsequent breakdown of carbon and fluorine chains are under intense research. Activated carbon (AC) is a widely used adsorbent for PFAS removal from water or wastewater. However, some of its shortcomings include inefficiency in short-chain PFAS removal, a lack of selectivity, overall low adsorption performance, and concerns regarding economic sustainability. Herein, we reviewed the recent innovative carbon-based technologies that aim to address these challenges. In particular, we focus on AC’s topography engineering, defunctionalization (e.g., removing surface functional groups), hydrophobicity or surface charge modification, water-confining nanopores, and AC-nanobubbles synergy. The underlying mechanisms of these novel approaches and their effectiveness in PFAS adsorption are discussed, along with their advancements and limitations. Additionally, the PFAS adsorption and regeneration ability of high-performance ACs are presented and compared. Finally, we address current challenges and offer perspectives on advancing this technology.

Formed via the physical, chemical, and biodegradation of plastic products, Microplastics (MPs) are plastic fragments smaller than 5 mm. As a notable contributor to environmental pollution, MPs have gained significant attention owing to their wide application and potential toxicity. MPs have been reported to accumulate in mammalian reproductive organs, adversely affecting male sperm quality, and pose a serious threat to male fertility. Therefore, it is important to understand how MPs exposure impacts sperm and the male reproductive system. This manuscript reviews the research progress of MPs exposure on sperm toxicity from three aspects: the effect of MPs on spermatogenesis and sperm quality, the ‘Trojan horse effect’ and cross-generational effect of MPs. The findings indicated a significant correlation between MPs exposure and reduced sperm quality reduction as well as abnormal spermatogenesis. Additionally, the study highlights the ‘Trojan horse effect’ and cross-generation toxicity of MPs in mammals. This manuscript also reviews current treatment approaches for MPs exposure, providing a valuable theoretical foundation for future scientific research and clinical interventions. In summary, this review emphasizes that MPs can impair male reproductive health through mechanisms such as inflammatory responses, hormonal disruption, and sperm toxicity. By consolidating current evidence, this work lays a foundation for future research to further investigate the molecular pathways and long-term effects of MPs on male fertility.

The present study aimed to identify the major pollutants, contamination characteristics, spatial distributions, health risks, and remediation projects associated with pesticide sites and discuss challenges and countermeasures for remediation projects in the new era. Over 100 full-process environmental management reports were collected from 57 sites and analyzed. The results showed that heavy metals, BTEX, chlorinated hydrocarbons, and organochlorine pesticides were the main pollutants at pesticide industry sites in China, for instance, arsenic (PI_mean = 45.88), benzene (PI_mean = 3315.35), trichloroethylene (PI_mean = 7887.76), and hexachlorocyclohexane (PI_mean = 8087.04). Most (> 70%) sites contained soil and groundwater contaminated by a combination of multiple pollutants. Furthermore, heavily polluted sites were widely distributed in industrially developed eastern coastal areas and in the agriculturally developed Yellow River Basin, Yangtze River Basin, and North-east China. Arsenic, benzene, chloroform, and hexachlorocyclohexane were identified as the key pollutants contributing to health risks. For instance, the average carcinogenic risk of hexachlorocyclohexane can reach 2.00E-01, while the average non-carcinogenic risk of chloroform can reach 573.04. Notably, the use of off-site and one-site ex situ techniques is still common for soil remediation, whereas in situ remediation techniques are used for groundwater. However, restoration projects face challenges such as neighbor avoidance, sustainable development, and climate change in the new era, which can be addressed by optimizing management systems and improving technical systems. Overall, our findings provide a reference for pollution prevention and control of pesticide production enterprises, risk management of decommissioned enterprises, and research and development of targeted green and sustainable remediation technologies.

Direct membrane filtration (DMF) is a popular option for raw sewage pre-concentration for the subsequent organic resource recovery. It undergoes rapid and severe fouling. To achieve a fundamental understanding of the contributions of key foulants to DMF, principal component analysis (PCA) using Fourier transform infrared spectroscopy (FTIR) was applied to identify three stages of DMF. Variance partitioning analysis (VPA) and partial least squares (PLS) were used to quantitatively determine the contributions of key foulants. Humic acid (HA) achieved the highest intersection contribution (40.5%) to the total variance of the increase in resistance. Meanwhile, HA and protein (PN) explained 20.1% in the middle stage of DMF. The overall marginal effect of HA accounted for 42.5% of the variance, in conjunction with an overall individual effect of 11.0% (which was the highest in the initial stage: 15.1%). The variable importance in projection (VIP) of impact on the resistance increase of DMF were 1.16 (PN), 0.99 (HA), and 0.82 (polysaccharides, PS). HA&PN with a VIP value approaching or larger than one significantly influenced the resistance increase in DMF. Meanwhile, the VIP of impact on blocking model alteration were 1.03 (PS), 1.01 (PN), and 0.96 (HA). HA, PS, and PN were regarded as vital factors in the fouling mode alteration. PS drives the fouling mode in the initial stage, whereas HA&PN and PN play dominant roles in the middle and final stages. Measures targeting HA and PN removal can be adapted for the efficient and cost-effective fouling control of raw sewage DMF.

Sulfur autotrophic denitrification (SAD) is a promising biological nitrogen removal technology without CO₂ emissions. However, the impact of seasonal temperature variations on SAD performance, especially in the treatment of actual municipal secondary effluent, remains unclear. To address this issue, a composite substrate SAD reactor (i.e., SPSAD), where element S⁰ and pyrite (v:v/1:3) were uniformly mixed in hollow plastic balls that served as the filler, was developed in this paper. The performance of the SPSAD reactor was comprehensively evaluated under 190 d of seasonal variation. The results indicated that the nitrate removal loading (NRL), nitrate removal efficiency (NRE), and PO₄³⁻-P removal rate decreased from 0.060 kg NO₃⁻-N /(m³·d), 93.2% and 67.9% to 0.032 kg NO₃⁻-N /(m³·d), 49.9% and 30.2%, respectively, when the temperature decreased from 35 °C to 9 °C. The SPSAD reactor was effective at performing denitrification under temperature variations. Additionally, the ratio of ΔSO₄²⁻ to ΔNO₃⁻-N gradually decreased from 6.48 to 5.34 as the temperature decreased, revealing a shift in the predominant electron donor for denitrification from S⁰ to pyrite. Microbial analysis revealed that the average abundance of Proteobacteria was 53.11%, making it the dominant phylum in the reactor. Thiobacillus was significantly enriched as the predominant genus responsible for denitrification, with its abundance decreasing from 33.2% at Stage I (25–35 °C) to 26.4% at Stage III (9–11 °C). The feasibility and advantages of NO₃⁻-N and PO₄³⁻-P removal via the SPSAD reactor were discussed and demonstrated in practical applications. This study provides stakeholders with scientific support for the deep treatment of municipal secondary effluent in cold areas.

Arsenic (As) contamination in vegetables poses significant ecological and health risks, raising substantial public concern. While arsenic accumulation and transformation have been studied, the in-situ iodination effects and mechanisms under co-contamination with arsenic and phenolic pollutants (e.g., bisphenol F) remain unclear. This study addresses this gap by exposing Brassica chinensis L. to hydroponic solutions containing sodium hydrogen arsenate heptahydrate (As(V)) at concentrations of 0–100 μmol/L, BPF at 3 mg/L, and iodide ions at 40 μmol/L under environmentally relevant conditions. Results demonstrate that As(V) enhances the iodination of BPF by increasing levels of reactive oxygen species (H₂O₂ and •OH) and elevating peroxidase (POD) activity, as confirmed by transcriptomic analysis. As the concentration of As(V) increased from 0 to 100 μmol/L, the diversity and concentration of iodinated BPF products in the roots exhibited a dose-dependent increase, while the variety of iodinated products in the leaves also showed a corresponding rise. Gaussian calculations and mass spectrometry identified the specific substitution sites and the number of iodide atoms incorporated into BPF molecules. By combining toxicity predictions of iodinated BPF using the Toxicity Estimation Software Tool (T·E·S·T) and the Ecological Structure-Activity Relationships (ECOSAR) model with measurements of HepG2 cell viability and lactate dehydrogenase (LDH) activity in the cell culture medium, it was found that the toxicity of iodinated BPF products in plants increased following the addition of As(V). This study highlights the combined risks of arsenic and bisphenol contamination, revealing arsenic’s role in enhancing bisphenol iodination and toxicity in plants.

Wastewater and CO₂ generated and discharged in scattered sites from small-scale factories and workshops in underdeveloped industrial regions have posed a serious threat to global ecology and health for decades. Interestingly, it has been demonstrated that some industrial wastewater can absorb carbon dioxide from exhaust gas. This presents a cost-efficient solution to mitigate pollution from carbon emissions. This review introduces the innovative concept of large-scale mutual remediation of these two types of wastes. By closely examining existing research on the subject, the potential challenges of implementing such a remediation strategy are thoroughly evaluated. Specifically, the process of mutual remediation yields positive results for both air and water quality: 1) direct absorption of carbon dioxide from tail gas or air; 2) removal of aqueous alkalinity, calcium, and heavy metals from various types of industrial wastewater; 3) transformation of nitrogen, phosphorus, and organic pollutants found in industrial wastewater; and 4) generation of valuable byproducts such as carbonates and biomass. Barriers to the widespread adoption of this remediation method include high cost, insufficient treatment, and difficult collection and transportation of wastes, which can be overcome by increasing product value, integrating the method with other processes, and building small-scale low-carbon industrial parks, respectively. Finally, current research gaps and future work are highlighted to advance the development of mutual remediation of wastewater and carbon emissions in underdeveloped industrial areas and facilitate green industrial development.

This study investigates the accumulation characteristics and cost-benefit evaluation of the monoculture modes of Pteris vittata (MP) and Hylotelephium spectabile (MH), as well as their intercropping with peach (LP and LH) in arsenic (As)- or cadmium (Cd)-contaminated orchards. The intercropping modes exhibited remediation efficiencies comparable to those of their respective monocultures. Soil As/Cd concentrations were projected to fall below risk intervention values in the 21st, 22nd, 34th, and 30th years for MP, LP, MH, and LH, respectively. The gross ecosystem product (GEP) of the intercropping modes significantly exceeded that of the corresponding monoculture, with peach profits contributing 85.8%–97.0%. The net present values (NPV) were achieved in 7 and 2 years for LP and LH, respectively. Furthermore, the economic viability of intercropping was primarily influenced by the economic benefits of peach and accumulator cultivation costs. These findings suggest that intercropping with peach provides economic benefits over monoculture in the management of As- or Cd-contaminated orchards. However, further optimization of seedling cost, disposal technologies, and mechanization of accumulator cultivation is required to enhance the feasibility.