Heavy metals contamination in coastal sediments poses potential ecological and human health risks due to their persistence, bioaccumulation, and remobilization under changing environmental conditions. In this study, eight heavy metals (Cu, Mn, Zn, V, Cr, Ba, Be, and Ti) were analyzed in 118 sediment samples collected from five representative bays along the northern South China Sea. The concentrations of heavy metals were determined using inductively coupled plasma-optical emission spectrometry (ICP-OES). Multivariate statistical analyses, including correlation analysis, principal component analysis (PCA), and positive matrix factorization (PMF), were applied to elucidate spatial distribution patterns and source contributions. Sediment quality and potential toxicity were assessed using multiple indices-the geoaccumulation index (Igeo), sediment toxicity degree (STd), and toxic equivalent concentration (TEQ). The results indicated that heavy metals contaminations were generally at low to moderate levels, exhibiting significant spatial heterogeneity among bays. Zn, Cu, and Mn were identified as dominant contributors to potential ecological risks, mainly linked to industrial and port-related activities. Human health risk assessment revealed negligible non-carcinogenic risks (hazard index, HI < 1) for both adults and children, although children showed higher cumulative susceptibility. Overall, this study provides an integrated ecological and health risk evaluation of heavy metals in coastal sediments of the northern South China Sea, offering valuable insights for regional pollution control and sustainable coastal management.

The rapid expansion of China's agro-livestock sector has intensified the challenges of lignocellulosic waste management owing to the recalcitrant structures of these materials during conventional composting. This study evaluated synergistic pretreatment strategies combining high-temperature (110 degrees C) with acid/alkali treatment (0.1 mol/L H2SO4 or Ca(OH)2) to enhance the composting efficiency of cherry wood. Results showed that pretreatment disrupted the lignocellulose structure and functional groups of cherry wood. In addition, combined treatments markedly reduced lignin content (AcHTW: 140.24 mg/g; AlHTW: 161.03 mg/g) than that of single pretreatments (AcYTW: 225.87 mg/g; AlYTW: 221.20 mg/g). Acid-high-temperature (AcHTW) and alkali-high-temperature (AlHTW) pretreatments promoted lignocellulose depolymerization, reducing hemicellulose to 70.62 mg/g (AcHTW) and cellulose to 118.25 mg/g (AlHTW) and 138.90 mg/g (AcHTW), respectively. The high-temperature-based synergistic pretreatments demonstrated superior humification performance, elevating humic acid (HA) content to 225.61-253.84 mg/g with corresponding humification indices (HIX) of 0.732-0.780, representing 6.2-13.2 % enhancement over untreated controls (HIX: 0.689). Microbial analysis identified Acinetobacter, Comamonas, Psychrobacter, and Pusillimonas as the dominant genera associated with humification, while Gimesia and Ferrovibrio were positively correlated with lignin degradation. Random forest and PLS-PM modeling indicated that bacterial diversity directly promoted lignocellulose decomposition (path coefficient: 0.274*) and humus formation (0.236*), whereas lignocellulose exerted a strong inhibitory effect on humus accumulation (0.770***). These processes were primarily driven by carbohydrate metabolism (15.68 %) and the synergistic action of laccase and cellulase. Overall, acid/alkali-high-temperature pretreatment alleviated microbial inhibition and enriched functional taxa, providing mechanistic insight into lignocellulose valorization during composting.

Insulin and insulin-like growth factor 1 (IGF1) play key roles in fetal growth and development. However, their roles in the association between fetal growth and perfluoroalkyl and polyfluoroalkyl substance (PFAS) exposure remain unclear. In this study, the levels of 34 PFAS, IGF1, and insulin were measured in 258 paired mother-infant serum samples collected from a nested case-control study in Maoming city. Isomeric perfluorooctanesulfonate (PFOS) exposure significantly increased the preterm birth or low birth weight (PTB/LBW) risk, and the odds ratios for ∑2m, 3+4+5m, iso, and branched PFOS were 1.50, 1.72, 1.61, and 1.77, respectively. Cord IGF1 could explain 15.4, 13.4, 9.7, and 11.9% of these associations, respectively. Additionally, cord IGF1 mediated 12.3 to 44.6% of the associations between PFOS isomers, perfluorooctanoate acid (PFOA), and its alternative (perfluorobutanoic acid: PFBA) with a fetal growth index. For instance, cord IGF1 contributed 42.0% (95% Cl: 0.8, 140.0%), 42.7% (95% Cl: 13.0, 110.0%), and 43.0% (95% Cl: 8.4, 130.0%) to the associations between z-scores of birth weight and branched PFOS, PFOA, and PFBA, respectively. These findings suggest that cord IGF1 plays a mediating role in the associations between PFAS exposure and fetal growth.

The remediation of heavy metal-contaminated soils via biochar involves both adsorption and microbial community regulation, yet the impact of environmental aging on this synergistic mechanism remains unclear. This study analyzed the aforementioned mechanisms through biochar-soil co-cultivation, batch adsorption experiments and 16S rRNA gene sequencing. The results revealed that the initial introduction of biochar did not significantly enhance heavy metal immobilization. After one year of natural aging, however, the efficacy of biochar in immobilizing heavy metals was closely associated with their initial residual fractions. When the inherent residual fraction was high e.g., Cu (> 94 %), biochar amendment induced negligible change in metal speciation. In contrast, in soils with low residual fractions, a 5 % biochar addition promoted the transformation of heavy metals into residual forms, resulting in maximum increases of 3.2 % for Pb and 7.2 % for Cd. Moreover, the stable fractions of heavy metals in biochar-remediated soils increased slightly with extended incubation time. After natural aging for one year, the content of mineral-related fractions increased significantly, substantially enhancing the adsorption (e.g., Kd increased to 499, 607 and 2114 mg/kg for Cu2 +, Cd2+ and Pb2+ with 5 % biochar addition after 1-year incubation) of heavy metals on biochar-remediated soil. Additionally, after natural aging, biochar amendment enriched key metal-immobilizing microbial genera (e.g., Gemmatimonas, Sphingomonas, and Acidiferrimicrobium), while reducing the abundance of metal-mobilizing Kouleothrix, which exhibited dose-dependent. This study demonstrated environmental aging enhanced the ability of biochar to remediate heavy metal-contaminated soil through combined adsorption and microbial community regulation.

Decabromodiphenyl ethane (DBDPE), a chemical compound widely detected in aquatic ecosystems, has shown a range of toxicological effects in zebrafish (Danio rerio). However, its effects on zebrafish reproduction remain underexplored. In this study. Adult zebrafish were exposed to 0, 1, 10, and 100 μg/L of DBDPE for 21 days. DBDPE accumulated in the gonads, leading to a marked decrease in both cumulative spawning and gonadosomatic index in female zebrafish. To investigate the mechanisms underlying reproductive abnormalities induced by DBDPE, we measured serum hormone levels, oocyte development, and gene expression in the hypothalamic–pituitary–gonadal (HPG) axis. Our results showed that exposure to DBDPE significantly reduced estradiol (E2) levels in female zebrafish, along with abnormal oocyte development and disrupted gene expression in the HPG axis. Further metabolomic and lipidomic analyses revealed considerable changes in taurine and hypotaurine metabolism, glutathione metabolism, and the FoxO signaling pathway, along with significant disturbances in lipid metabolism. These disruptions in metabolic pathways may be an important underlying cause of delayed oocyte development. Our findings show that exposure to DBDPE delays oocyte development by altering lipid metabolism, reducing sex hormone levels, and impairing HPG axis regulation, ultimately leading to reduced fecundity in female zebrafish. This study highlights the repercussions of DBDPE exposure on the reproductive health of zebrafish, emphasizing the need for stricter regulation of its production and use, a well as a comprehensive reassessment of the risks it poses to fish.

Understanding contaminant transformation during wastewater treatment is essential for pollution reduction and environmental risk mitigation. However, the highly diverse molecular composition of wastewater, arising from various emission sources, presents a major challenge to deciphering the underlying biochemical reactions. Herein, nontargeted analysis and paired mass distance (PMD) analysis were conducted in paired influent-effluent samples from 11 wastewater treatment plants to elucidate contaminant diversity and transformation reactions across different treatment processes. In total, 418 structural subclasses of contaminants were classified, among which amino acids, peptides, and analogues (AAPAs) were the most common. Although the total number of features, subclasses, and overall abundance decreased in effluent samples, chemical diversity did not show a consistent reduction. This finding was primarily due to the removal of contaminants such as AAPAs and the persistence of aromatic compounds such as benzenoids. Transformation reactions were highly conserved across biological processes, with methylation and demethylation occurring the most frequently. High-frequency PMDs were strongly associated with carbon-related transformations, which substantially altered the polarity of transformation products. Furthermore, transformation reactions were characterized by small mass shifts and intrastructural reactions, indicating that most contaminants did not undergo extensive structural transformations. This study provides insight into common patterns of contaminant removal across wastewater treatment processes, benefiting transformation product prediction and wastewater treatment process optimization.

The widespread adoption of alternative plasticizers (APs) has raised global concerns over their environmental and health impacts. An alternative assessment is required to evaluate the safety of potential alternatives for hazardous chemicals. This study reports a comprehensive multicriteria alternative assessment (MCAA) framework that integrates 15 hazard end points across human health hazards, ecotoxicity, and environmental fate. By utilizing a hierarchical protocol to harmonize multitiered data from authoritative global sources, the MCAA assigns definitive safety ratings from Level 1 (safer) to Level 4 (more hazardous). Using this MCAA framework, we evaluated 522 currently used plasticizers, including 296 APs. The results revealed that the plasticizer percentages in Levels 1, 2, 3, and 4 were 4.60%, 12.07%, 38.12%, and 45.21%, respectively. Time-trend analysis of newly registered plasticizers (2000-2024) revealed a progressive shift toward safer alternatives, with the proportion of Levels 1 and 2 compounds increasing from 0% to 66.67%. Mobility and aquatic toxicities were identified as the key end points with the highest contributions to the overall hazard, highlighting that the ecological impacts were historically overlooked compared with the human health. The MCAA framework provides a scientifically rigorous protocol to support the environmental and health risk management of APs.

The health risks of organophosphate esters (OPEs) have attracted increasing attention, yet information on their occurrence, transformation, and interactions with microorganisms remains limited. In this study, dust samples from various indoor microenvironments were collected and analyzed for 17 tri-OPEs and 9 transformation products (TPs), alongside characterization of bacterial communities. Both tri-OPEs and TPs were ubiquitous, with higher concentrations in public places than in residences. TPs may originate from both the degradation of parent tri-OPEs and direct commercial applications. Proteobacteria, Actinobacteriota, and Firmicutes dominated the bacterial community, with Staphylococcus as the predominant genus and numerous potential pathogenic taxa identified. Indoor OPE exposure was significantly associated with bacterial community composition (PERMANOVA, p < 0.001), with markedly stronger genus-compound associations in residences than in public microenvironments. Functional gene predictions revealed phosphatase-mediated pathways potentially involved in OPE biotransformation. Predicted pathogenic potential indices were higher in public environments and positively correlated with OPE and TP levels (p < 0.01). Although overall hazard quotients (HQs) indicated low non-carcinogenic risks, several TPs showed HQs and predicted receptor-binding affinities comparable to those of tri-OPEs. A ToxPi-based multi-dimensional assessment, incorporating HQs, receptor binding, physicochemical properties, and microbial associations, prioritized aryl tri-OPEs as the most concerning group, while several TPs also ranked highly, warranting further regulatory attention. This study highlights the critical role of linking chemical contamination in indoor dust with microbial characteristics for health risk assessment.

Microplastics (MPs) are known to induce diverse toxic effects across biological systems; however, how environmentally photoaged MPs influence organismal aging and the underlying mechanisms remain poorly understood. Here, virgin polystyrene (PS-0) and 45-day photoaged polystyrene (PS-45) were evaluated at environmentally relevant concentrations (0-100 μg/L) to assess aging-related effects and molecular pathways in Caenorhabditis elegans. Photoaging markedly altered PS physicochemical properties, including surface morphology, crystallinity, and functional groups. Exposure to 100 μg/L PS-0 or PS-45 significantly shortened lifespan, impaired physiological behaviors, and increased lipofuscin accumulation, whereas PS-45 at 10-100 μg/L elicited substantially stronger pro-aging effects. These enhanced toxicities were driven by particle-associated processes, particularly elevated environmentally persistent free radical generation and increased particle accumulation in nematodes. Mechanistically, PS-45 inhibited DAF-16 nuclear translocation and dysregulated insulin/IGF-1 signaling genes (daf-2, age-1, pdk-1, akt-1, and daf-16). Concurrently, PS-45 induced ferroptosis, as evidenced by increased Fe2+ and malondialdehyde levels, glutathione depletion, and suppression of ftn-1; these effects were alleviated by the ferroptosis inhibitor ferrostatin-1. Mutations in daf-2, age-1, pdk-1, akt-1, daf-16, and ftn-1 significantly altered PS-45-induced aging phenotypes and ferroptotic stress, identifying the DAF-2-AGE-1-PDK-1-AKT-DAF-16-FTN-1 axis as a central regulatory pathway. Collectively, this study reveals a mechanistic link between insulin signaling and ferroptosis in MPs-induced aging and highlights the elevated environmental health risks posed by photoaged MPs.

With the ongoing degradation of aquatic ecosystems, the identification of environmental stressors presents a significant scientific challenge, constrained by methodological limitations. This study proposes an integrative strategy combining ecotoxicoproteomics, in vitro/in vivo bioassays, and advanced chemical analyses to identify stressors and assess their hazards through biomarker discovery and adverse outcome (AO) validation. When applied in the Yellow River Estuary, this approach revealed key findings: Ecotoxicoproteomic analysis of sentinel species, crucian carp (Carassius auratus), identified membrane receptor integrin αvβ3 as a key biomarker linked to neurotoxicity-related AOs. An in vitro competitive binding assay revealed higher integrin αvβ3 binding activity in mainstream versus tributary samples. Comprehensive chemical analysis identified triethyl phosphate (TEP) as the primary causative toxicant, accounting for over 46% of integrin αvβ3 binding activity. In vivo studies confirmed that TEP induced dose-dependent neurodevelopmental toxicity and locomotor dysfunction in crucian carp, with a benchmark dose lower confidence limit of 120 ng/L, aligning with environmental concentrations of 87.52-328.84 ng/L in the mainstream. This study substantiates TEP as an emerging stressor that induces locomotor dysfunction in fish within the study area. By establishing a novel identification strategy for environmental stressors, it provides a scientific foundation for mitigating aquatic ecosystem degradation in the Yellow River Estuary.

Transport of per and polyfluoroalkyl substances (PFAS) to the Yangtze River is a growing concern because the river provides drinking water for over 400 million people. However, tributary PFAS inputs to the Yangtze River remain poorly characterized, and the potential risks in numerous tributaries are largely unknown. In this study, 29 legacy and emerging PFAS were quantified in water (13.3–316 ng/L), suspended particulate matter (SPM) (0.67–40.2 ng/L), and sediment (0.52–387 ng/g) collected from the Three Gorges Reservoir (TGR) region of the Yangtze River and its tributaries. Perfluorobutyric acid (PFBA) was the most abundant individual PFAS in water, whereas perfluorooctanoic acid (PFOA) and 6:2 fluorotelomer sulfonic acid (6:2 FTS) were the predominant compounds in SPM and sediment, respectively. Our analysis reveals that PFAS discharge from tributaries is a dominant contributor to PFAS accumulation in receiving waters. While larger tributaries in the TGR region generally exhibit lower aqueous PFAS concentrations than smaller tributaries, they account for the majority of the total PFAS flux entering the Yangtze River. Our results demonstrate that PFAS alternatives, including PFBA, perfluorohexanoic acid (PFHxA) and 6:2 FTS, are growing in relative prominence as replacement compounds for legacy PFAS. PFBA and PFOA were found to pose potential ecological and human health risks in tributary water, highlighting the need for future regulatory measures concerning these PFAS compounds in the tributaries of the TGR region.

Benzo[a]pyrene (BaP) is a persistent combustion-derived polycyclic aromatic hydrocarbon (PAH) that causes widespread human exposure. BaP has been classified as a Group I carcinogen by the International Agency for Research on Cancer (IARC), with sufficient evidence supporting its carcinogenicity in multiple target organs, primarily through metabolic activation-mediated genotoxicity. Increasing evidence indicates that BaP and its metabolites also contribute to tumor promotion and progression by regulating cellular survival, metabolic adaptation, malignant transformation, intercellular communication, and immune microenvironmental remodeling. In addition, BaP may interact with co-occurring environmental chemicals to produce synergistic or antagonistic carcinogenic effects, yet the mechanisms underlying these interactions remain insufficiently defined. Existing reviews have mainly focused on specific mechanisms or exposure settings, limiting a multidimensional understanding of BaP carcinogenicity under complex environmental exposure scenarios. Here, we synthesize classical evidence and recent advances in BaP-induced carcinogenicity across four interconnected dimensions: cancer occurrence in different tissues, the role of BaP in cancer initiation, promotion, and progression, key molecular mechanisms, and co-carcinogenic interactions with other chemicals. This review highlights that BaP carcinogenicity extends beyond genotoxic initiation and involves stage-dependent, tissue-specific, and interaction-driven processes. We further propose future priorities, including gaining a deeper understanding of tissue-specific regulatory networks, applying omics-based approaches to define carcinogenic signatures, and elucidating interaction mechanisms under realistic chemical co-exposure scenarios. This synthesis provides a framework for more mechanism-informed assessment of BaP-related environmental health risks and mixture carcinogenicity.

Personal-care-product-derived microbeads are an important source of primary microplastics (MPs), yet their environmental transformation and toxicity remain unclear. Here, facial scrub (FS) microbeads were subjected to simulated photoaging and evaluated in zebrafish larvae at an environmentally relevant concentration. Photoaging promoted the formation of environmentally persistent free radicals (EPFRs), altered FS physicochemical properties, and enhanced the release of organic additives and heavy metals. Compared to virgin FS, photoaged FS (FS-60) induced stronger neurobehavioral impairment, including reduced tail coiling, swimming activity, and inner zone duration, mainly driven by leachates and EPFR-associated reactivity. Transcriptomic and biological analyses revealed disrupted mitochondrial function and neuronal signaling. FS-60 impaired central nervous system and motor neuron development, altered neurotransmitter levels (acetylcholine, serotonin, and γ-aminobutyric acid), and downregulated neurodevelopment-related genes. Moreover, FS-60 induced mitochondrial dysfunction, as supported by TEM-observed mitochondrial structural damage, elevated reactive oxygen species (ROS) and cytochrome c release, reduced ATP production and NAD+/NADH ratios, and suppressed electron-transport-chain-related genes. Mitoquinone mesylate (MitoQ) significantly alleviated locomotor deficits and ROS accumulation, confirming mitochondrial dysfunction as a key driver of FS-induced neurotoxicity. This study demonstrates that photoaging amplifies the neurotoxicity of cosmetic microbeads and should be considered in ecological risk assessment.

Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants widely distributed in the environment and linked to adverse health effects. Yet integrated assessments across multiple media, exposure pathways, and environmental scenarios remain limited. Here, we applied a multi-media, multi-pathway framework to estimate population exposure to PAHs and associated carcinogenic risks in China. PAH concentrations in air, water, soil, dust, and food were compiled from studies published between 2010 and 2024. Average daily doses (ADDs) were calculated for dietary intake, inhalation, oral ingestion, and dermal contact pathways, while carcinogenic risks were quantified using benzo[a]pyrene equivalents (BaPeq) and incremental lifetime cancer risk (ILCR). PAH levels differed markedly by medium and scenario: industrial areas showed higher concentrations in air and water, while urban areas were characterized by elevated dust and soil burdens; rural areas were generally lower. In the primary assessment, dietary intake contributed substantially to both total PAH exposure and carcinogenic risk. A percentile-based dietary scenario analysis showed that the industrial-urban-rural risk ranking remained stable within each age group, although absolute total ILCR values and some age-group comparisons were sensitive to dietary-pathway uncertainty. Monte Carlo and sensitivity analyses further indicated that pathway-specific ILCR variability was most strongly associated with medium-specific BaPeq concentrations.

Microplastics (MPs) are pervasive vectors for hydrophobic organic contaminants in soil ecosystems, yet their ecological impacts under environmentally relevant conditions remain insufficiently characterized. This study investigated effects of ultraviolet aging on polyethylene (PE) and polyvinyl chloride (PVC) MPs, focusing on changes in their physico- chemical properties, the associated effect on adsorption of Tetrabromobisphenol A (TBBPA) and tetrabromobisphenol S (TBBPS), and bioaccumulation of TBBPA/S in earthworms. Aging increased the surface roughness and abundance of oxygen-containing surface functional groups on PE MPs, and significantly increased the adsorption of TBBPA (24.9%) and TBBPS (10.6%). In contrast, only limited enhancement in TBBPA/S adsorption was observed for PVC MPs, while the time to reach adsorption equilibrium for TBBPA was shortened significantly due to the optimized pore connectivity brought by aging. The bioaccumulation of TBBPA/S in earthworms was strongly influenced by the type of MPs, aging status, and exposure conditions. Results of biokinetic modeling show that the inherent polymer properties of MPs play a dominant role in the uptake of TBBPA/S by earthworms. With high free volume, PE MPs mainly promoted TBBPA/S bioaccumulation through MP intake (up to 97%), while bioaccumulation of TBBPA/S mainly occurred through skin adsorption in the presence of the rigid-chained PVC MPs (up to 99.8%). The pollutant's hydrophobicity also impact its bioaccumulation pathways, with the MP-affiliated uptake playing a more important role in the case of pollutant with higher Kow. These findings help better understand the ecological and toxicological implications of combined microplastic and organic pollutant contamination in soil systems.

Halogenated phenols and bisphenols are metabolic-disrupting chemicals related to electronic waste (e-waste) dismantling activities. However, their adverse effects on lipid metabolism and the underlying mechanisms remain insufficiently understood. Based on a cross-sectional study of 227 e-waste workers and residents from an e-waste recycling area in China, we measured 11 urinary halogenated phenols and bisphenols, quantified four serum lipid parameters, and performed untargeted serum metabolomics. Dyslipidemia and its subtypes (hypercholesterolemia, hypertriglyceridemia, and hyper low-density lipoprotein cholesterol) were defined according to clinical criteria. After covariate adjustment, six phenolic compounds (PCs) and their mixture were associated with increased odds of dyslipidemia and its subtypes, with 3,5-dichlorophenol contributing most to dyslipidemia, hyper low-density lipoprotein cholesterol, and hypertriglyceridemia, whereas 3,4-dichlorophenol contributed most to hypercholesterolemia. Stronger associations were observed in males, normal-weight individuals, and those aged <60 years. Mediation analysis identified nine metabolites that significantly mediated these associations (proportions mediated: 14.8%-63.7%), annotated to amino acid, energy, and retinol metabolism pathways. Hierarchical partitioning revealed that PC exposure alone explained 4.28% of the variance in lipid metabolism, indicating a meaningful contribution. These findings provide potential mechanistic insights into the associations of halogenated phenol and bisphenol exposure with lipid homeostasis and highlight the need to reduce exposure to these chemicals among e-waste workers and nearby residents.

Escalating global electronic waste (e-waste) generation contrasts with <20% formal recycling rates. Policy gaps and inadequate enforcement exacerbate pollution transfer to under-regulated regions, causing substantial environmental and health problems. To address this, we investigated chronic exposure hazards and developed rapid pollution identification technologies. We recruited 2028 participants from e-waste recycling sites and other industrial parks, profiling their urinary organic pollutant exposome (>200 chemicals), oxidative damage, and metabolome by integrating nontargeted and targeted screening methods. Results showed that exposure to pollutant mixtures was significantly associated with increased oxidative damage to nucleic acids and cholesterol. Moreover, these pollutant mixtures collectively explained 46.2% of the variance in urinary metabolome alterations among e-waste workers. The affected metabolites were primarily associated with inflammatory diseases, metabolic disorders, neurological conditions, and cancers. By identifying e-waste exposure characteristic pollutants, we further developed accurate e-waste exposure prediction models (AUC > 0.986; ACC > 0.938) and derived simplified prediction functions and diagnostic indexes with comparable efficacy, which performed well across populations and industrial settings. Overall, this study underscores the significant health risks of e-waste exposure in occupational workers and offers rapid screening tools for e-waste pollution in informal settings, advancing the repurposing of large-scale national exposure monitoring databases for pollution tracking.

The effective monitoring and selective removal of hexavalent chromium (Cr(vi)) are critical for aquatic environmental remediation and human health protection. Herein, a series of binary and ternary covalent organic frameworks (COFs) containing donor-acceptor linkages or hydroxyl nanotraps were synthesized via a molecular engineering strategy for simultaneous detection, selective adsorption, and photocatalytic reduction of Cr(vi). The optimized ternary COF (BTD-OH-COF) outperformed binary COFs containing only adsorptive or photocatalytic groups, exhibiting enhanced fluorescence properties, a rapid response to Cr(vi), and a limit of detection of 68 nmol L-1. Moreover, with its dual adsorption and photocatalytic functionalities, the BTD-OH-COF achieves a Cr(vi) removal efficiency of 99.9% under simulated sunlight irradiation without the use of sacrificial agents. Its removal efficiency was approximately 1.50 times higher than those of binary COFs, respectively. Theoretical and experimental results confirm that constructing hydroxyl adsorption sites with donor-acceptor photoactive units synergistically enhances adsorption capacity while significantly reducing the energy gaps, thereby facilitating electron-hole separation and boosting photocatalytic activity. This study provides novel design principles for bifunctional monitoring/photocatalytic materials and offers an innovative approach for remediating heavy metal pollution in water.

Mangrove ecosystems, located at the land-sea interface, are especially susceptible to land-based runoff carrying persistent environmental pollutants such as per- and polyfluoroalkyl substances (PFAS). Despite their ecological importance, the dynamics of PFAS contamination in China's mangroves remain poorly understood. We systematically assessed 15 mangrove wetlands across four southern provinces, revealing significant spatial variation in PFAS contamination. Mangrove sediments from Fujian exhibited significantly higher levels of PFOA and ΣPFAS compared to the other three provinces, while Guangdong showed notably higher concentrations of FOSA and N-EtFOSAA. PFOS levels were also significantly higher in Fujian and Guangdong than in Guangxi and Hainan, whereas PFPeA, PFTeDA, PFHxS or 6:2 FTS showed no significant differences. Sediment PFAS profiles across the four provinces showed some overlap, particularly for C5 − C7 PFCAs, C4 and C6 PFSAs, N-EtFOSAA and NaDONA. In contrast, surface seawater from Beihai and Guangzhou displayed distinct PFAS compositions: Beihai was dominated by PFBA, while Guangzhou had higher ratios of PFBS, C6 − C8 PFCAs, and 6:2 FTS. Both log KD and log KOC values exhibited significant positive correlations with carbon-chain length, with emerging PFAS exhibiting comparable or higher log KOC values than long-chain PFAAs. Socioeconomic indicators, including population size, GDP, and urbanization rate, were positively correlated with long-chain PFAAs, and negatively correlated with short-chain PFAAs, suggesting that urbanization and industrialization are potential factors associated with PFAS contamination patterns in mangrove sediments, and contributed to elevated PFOS risk in parts of Fujian and Guangdong.

Developing environmental functional materials for efficient aquatic antibiotics remediation remains a critical challenge. Herein, an iron-polyphenol coordination nanocluster (Fe-EA NC) consisting of iron and ellagic acid (EA) possessing unique electronic structures was synthesized and applied for effective ofloxacin (OFL) degradation. Notably, the abundant active sites and electron delocalization properties of Fe-EA NC enabled it to efficiently activate peroxydisulfate (PDS) generating diverse reactive oxygen species (ROS) and facilitating the non-radical pathways, achieving 95.9% OFL removal (initial concentration of 25 mg L-1) within 2 h, at low catalyst dosage of 0.125 g L-1. Single-factor experiments were conducted to confirm the robust catalytic degradation performance of Fe-EA NC under various environmental conditions with OFL degradation rate remaining over 90% in most cases, including variation of temperature and initial pH, and coexisting interferents. Furthermore, Fe-EA NC exhibited a favorable reusability (over 80% degradation after 5 consecutive cycles). Comprehensive analytics identified the catalytic sites, electron transfer, ROS, and alleviation of overall toxicity to a certain extent. Sufficient theoretical calculations elucidated reaction sites of OFL and catalyst structure-induced electron transfer at the molecular level. This work provides a rational design strategy for high-performance environmental catalytic materials by systematically investigating the molecular characteristics of the EA-based iron coordination complex with prominent electron delocalization properties caused by polyphenolic structure of EA, and the various PDS activation pathways resulting therefrom. Key findings include the formation of multiple efficient catalytic sites via intramolecular charge transfer and electron delocalization, and enhanced OFL electron extraction through intermolecular electron transfer.