Zero-valent iron (ZVI) is among the most widely applied micro-nano materials for environmental remediation. Despite its high efficacy toward pollutant removal, the long-term performance of ZVI is often hindered by surface passivation, which diminishes reactivity and necessitates regeneration. Here, we present a redox oscillation strategy for regenerating inactivated ZVI via cyclic microbial reduction and ambient oxidation. The regenerated ZVI exhibited substantially enhanced surface electron-donating capacity (2.5 × 10–2 mmol e– g–1) compared to inactivated ZVI (5.3 × 10–3 mmol e– g–1), along with recovered electron transfer kinetics (4.0 × 10–3 s–1) compared to inactivated ZVI (6.2 × 10–4 s–1). Consequently, regenerated ZVI achieved a 7.2-fold higher Cr(VI) reduction efficiency, together with improved removal of nitrate and p-nitrophenol. Mechanistic analyses revealed that regeneration was driven by the synergistic disruption and transformation of the passivating oxide layer: physical alteration increased surface area and porosity, while chemical transformation yielded low-crystalline iron oxides with enhanced surface redox activity. These modifications created additional surface reactive sites, thereby facilitating pollutant sorption and transformation. This study demonstrates redox oscillation as a promising approach to sustain the reactivity and durability of ZVI in remediation applications.

Anaerobic ammonium oxidation (anammox) is a promising enormous energy- and resource-saving technology for nitrogen removal. Conventional anammox relies on nitrite (NO2––N) for the oxidation of ammonium (NH4+–N) to dinitrogen gas (N2). However, the current partial nitrification process for NO2––N production exhibits inherent instability and substantial energy demands, restricting its practical application. To address such limitations, an upflow dual-chamber electrocatalysis-driven anammox membrane bioreactor (UEA-MBR), by employing ruthenium–iridium-coated titanium alloy electrodes, was constructed to minimize NO2––N dependence while achieving high nitrogen elimination. The newly developed UEA-MBR showed excellent performance in nitrogen removal at a NO2––N concentration (NH4+–N/NO2––N = 1:0.4) even much lower than the theoretical. This UEA-MBR achieved a remarkable total nitrogen removal efficiency of 89.7% and maintained 60.8% even without NO2––N supply. Besides the conventional anammox, the electrocatalytic anammox process by directly oxidizing NH4+–N to N2 while delivering electrons was confirmed as well in the bioanode. Moreover, the generated electrons, after being transferred into the cathode, were utilized to further drive the anammox-generated NO3––N to NO2––N via partial denitrification, which provided the self-produced NO2––N for the anodic conventional anammox process via recirculation of effluent and ensured the high-nitrogen removal. This electrocatalytic system enriched the key functional genus electroactive Candidatus_Brocadia (23.5%) and norank_o_Fimbriimonadales (13.8%) and upregulated the genes of hzs, nirS, and nirB, establishing a robust nitrogen removal bioreactor. This integrated UEA-MBR shows great potential in breaking the barrier of conventional NO2––N-dependent anammox, offering a novel strategy toward sustainable and low-carbon wastewater treatment.

Wastewater treatment systems face increasing pressure to balance pollution reduction with carbon control under climate-driven environmental variability. This study proposes a novel evaluation framework that integrates temporal autocorrelation analysis with pollution–carbon coordination assessment to address critical methodological gaps in current static evaluation approaches. The framework comprises a coupling coordination degree (CCD) index combining gray water footprint reduction efficiency and carbon emission intensity, systematic incorporation of the autocorrelation coefficient to characterize persistent influent fluctuation patterns, and an integrated prediction methodology for stability evaluation. The framework was validated through a 1,461-day study across four full-scale wastewater treatment plants encompassing Oxidation Ditch (OD), Anaerobic/Anoxic/Oxic (A2/O), A2/O with Membrane Bioreactor (A2/O-MBR), and Cyclic Activated Sludge System (CASS). Advanced configurations achieved superior coordination, with CASS and A2/O-MBR showing mean CCD values of 0.645 and 0.641 versus 0.572 and 0.591 for OD and A2/O processes. CASS maintained 94% of values within the primary coordination range, while A2/O-MBR achieved 85% combined presence in primary and intermediate levels. Temporal autocorrelation emerged as the primary stability determinant, with optimal performance at ACC values between −0.1 and 0.2. Deviations to ACC = ±0.8 increased the coefficient of variation by 34–68% and reduced high-coordination days by up to 27%. Sensitivity rankings positioned A2/O-MBR as the highest, followed by OD, CASS, and A2/O. The framework offers transferable methodological tools for technology selection and optimization, supporting evidence-based design of resilient wastewater infrastructure that explicitly accounts for temporal dynamics in pollution–carbon management strategies.

Bioplastics have been developed as alternatives to petrochemical plastics. The microbial biodegradation process is driven by enzymes involved in microbial metabolism. Amorphous structures that enhance enzyme affinity and biodegradation rates often compromise mechanical and thermal properties. In contrast, although crystal domain-rich bioplastics may exhibit excellent physical characteristics, they typically suffer from insufficient biodegradability. In this study, we explored the balance between crystallinity, enzymatic stability, and biodegradability. Our model Bioplastic is a silk fibroin Bioplastic that demonstrates a high β-sheet crystal content and enzyme-resistance, which contrasts with the properties of conventional silk fibroin materials. When buried in microbially activated compost soil, this Bioplastic achieves a notable composting rate of 72.1% over 8 weeks. Soil microbiome analysis revealed that compost maturation increases species diversity within microbial communities, enriching silk-degrading enzymes that accelerate biodegradation. This finding was further validated in biodegradation tests using commercial nursery soils containing plant materials. Taken together, soil microbiome activity emerges as one of the principal factors in eliciting the biodegradability of crystal-rich, enzyme-resistant bioplastics. Our work will contribute to developing future bioplastics that combine superior physical properties and high biodegradability.

The presence of emerging contaminants (ECs) in water bodies poses a serious threat to the environment and human health, and hence their removal from the environmental matrices is of paramount importance. Among different treatment technologies, the electro-Fenton (EF) process has demonstrated notable efficiency in eliminating these ECs; however, the hefty catalyst cost hampers its upscale applications. Therefore, this research aimed to devise an efficient, highly stable, and cost-effective electrocatalyst to facilitate Fenton reaction for efficacious removal of an EC, Atenolol from water matrices. Hence, a dual-cathode EF system modified with nitrogen-doped iron-absorbed biocarbon (N-FeBC) was employed for targeted removal of Atenolol from different water matrices. Comprehensive material characterization validated the successful synthesis of N-FeBC, with a prominent X- ray diffraction peak of Fe4N, corresponding to a 2θ value of 57.92 and 75.67°. Furthermore, the integration of N in the carbon structure was affirmed by peaks of pyrrolic and oxidized N in the X-ray photoelectron microscopy spectra. Electrochemical characterization including cyclic voltammetry, electrochemical impedance spectroscopy (EIS), and electrochemical active surface area (EASA) demonstrated superior electrocatalytic properties of N-FeBC. Notably, the EIS revealed a 12.7-fold decrease in charge transfer resistance and a 41% increase in EASA upon N-FeBC coating. During the EF treatment, 10 mg/L Atenolol was degraded entirely (∼99.9%) within 45 min at neutral pH and at an applied cathodic potential of 1.4 V vs standard calomel electrode from different water matrices. This enhanced removal can be credited to the perpetual formation of hydroxyl radical (•OH), identified through electron paramagnetic resonance signals. Further, the N-FeBC-catalyzed EF system also displayed high operational stability with just 0.7% efficiency loss per cycle and effectively fragmented Atenolol into benign, nontoxic intermediates as confirmed through the Ecological Structural Activity Relationships tool. Overall, this investigation showcases the efficacy of N-FeBC electrocatalyst for Fenton-mediated oxidation of refractory Atenolol from wastewater, which is in line with the sustainable development goals (SDGs) focusing on good health and well-being (SDG3), clean water and sanitation (SDG6), and life below water (SDG14).

Soil heavy metals and metalloids (heavy metal[loid]s) are detrimental to human and ecosystem health. However, their concentrations are not regularly tested in many regions because of the dangerous and time-consuming pseudo extraction methods required for chemical analysis. In comparison, the identification of exchangeable heavy metal(loid) concentrations is advantageous regarding risk and costs. This study demonstrates that the total heavy metal(loid) concentration can be accurately predicted using the exchangeable concentration, elemental descriptors, and soil properties. A systematic modeling process was used to develop the ExtraTrees model, which was built on a global data set containing 9557 data points. ExtraTrees achieved a testing R2 of 0.9 for predicting the total concentrations. Multiple model interpretation tools revealed that the exchangeable concentration and magnetic moment of the element were the key drivers for estimating total concentration. The relative soil arsenic (As) threshold map suggested that stricter thresholds should be adopted in southeastern and north-central China considering their potential susceptibility to soil As contamination based on safe grain production. This study presents a rapid and efficient method for evaluating heavy metal(loid) concentrations that eliminates the need for dedicated instruments. These findings provide new insights into identifying heavy metal(loid) contamination while offering valuable guidance for developing evidence-based contamination policies, formulating effective remediation strategies, and implementing cleaner crop production practices.

Locally enhancedelectric field treatment (LEEFT) isan emergingtechnology that employs electric fields to inactivate bacteria inwater. Compared to traditional chlorine-based solutions, LEEFT allowsfor efficient water disinfection while preventing the formation ofharmful disinfection byproducts. When combined with copper (Cu), amaterial recognized for its antimicrobial properties, LEEFT-Cu hasdemonstrated increased bacteria inactivation efficiency. In this study,LEEFT-Cu is tested for its disinfection performance against 8 differentbacteria (4 Gram-negative (G−) and 4 Gram-positive (G+)), eachgrown in both stable and exponential phases. The primary focus ison the effectiveness of LEEFT-Cu against both gram structures. Itis concluded that LEEFT-Cu can achieve >3 log removal for mostbacteriaspecies (7/8) using <0.7 mg/L Cu. Additionally, the calculateddegree of improvement using LEEFT-Cu in comparison to Cu ions aloneindicates >20 times increase in disinfection performance. The degreeof improvement also leads to the conclusion that G+ bacteria are upto 3 times more vulnerable to the impacts of EFT (i.e., increasedmembrane permeability) than G–. Future work should focus ontesting the current bench-scale prototype with more complex watermatrices to further advance LEEFT-Cu for practical applications inwater disinfection.

Drinking water distributionsystems contain chlorine and metalsthat can promote antibiotic resistance. Corrosion inhibitors are requiredto prevent the leaching of metals into drinking water. While utilitieshave a choice of which corrosion inhibitor they employ, the impactof corrosion inhibitor type when combined with chlorine on antibioticresistance is unknown. The objective of this research was to understandthe impacts of zinc orthophosphate, sodium orthophosphate, and sodiumsilicate, three commonly used corrosion inhibitors, on antibioticresistance when mixed with chlorine. Culture-based plating was pairedwith metagenomics analysis on lab-scale microcosms. The addition ofall three corrosion inhibitors resulted in a significantly higherabsolute abundance of antibiotic resistant bacteria with resistanceto rifampicin, sulfamethoxazole, and vancomycin, while the additionof phosphate-based inhibitors (sodium orthophosphate and zinc orthophosphate)at 1 mg/L also resulted in significantly higher absolute abundanceof ampicillin-resistant bacteria. Exposure to all three types of corrosioninhibitors and free chlorine led to significantly higher abundancesof ARGs conferring resistance to the target antibiotics used in thephenotypic assessment. Observed changes in the resistomes comparedto the controls were influenced by an enrichment in ARGs responsiblefor multidrug resistance and resistance to peptide antibiotics. Ingeneral, most of the ARGs were associated with chromosomes, but asignificant increase in the number of ARGs colocated with plasmidand integron sequences was observed. In contrast, the abundance ofviral-associated ARGs decreased in the treatments compared to thecontrols. These results highlight the importance of corrosion inhibitorselection and the potential impacts on antibiotic resistance in potablewater systems.