Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025010402
Vegetable consumption is a well-established pathway for human exposure to per- and polyfluoroalkyl substances (PFAS). These contaminants are absorbed by vegetables through uptake from soil and irrigation water, leading to bioaccumulation within plant tissues and posing potential risks to human health. Therefore, monitoring PFAS concentrations in vegetables is critical for assessing dietary exposure and associated health risks. In this study, a solid-phase extraction (SPE) followed by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the determination of 24 PFAS compounds in leafy vegetables, including Shanghai Bok Choy, Cabbage, and Water Spinach. The analytical method, incorporating organic solvent extraction followed by SPE cleanup, was optimized with respect to both extraction solvent and SPE sorbent. Alkaline methanol was used as the extraction solvent, and PFAS in vegetables were extracted via vortex-assisted extraction. Tandem mass spectrometry was used for detection in multiple reaction monitoring mode, and quantification was performed by internal standard method. Under optimized conditions, at a spiking level of 2 ng, recoveries ranged from 50.0% to 120.8% with relative standard deviations (RSD) between 1.0% and 26%. Calibration curves showed good linearity with correlation coefficients (r) greater than 0.99. Limits of detection (LOD, S/N=3) were between 0.002 and 0.103 ng·g−1, and limits of quantification (LOQ, S/N=10) were between 0.007 and 0.343 ng·g−1. The method was applied to real samples, detecting 20 PFAS, with 10 compounds showing 100% detection frequency. Total PFAS concentrations ranged from 2.92 to 6.83 ng·g−1 dry weight (dw). Perfluorobutanoic acid (PFBA) was the dominant contaminant, with concentrations from 1.18 to 3.74 ng·g−1 dw. The method demonstrates good sensitivity and accuracy, effectively identifying and quantifying multiple PFAS, thus providing reliable technical support for monitoring PFAS in vegetables.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025010608
This study investigated the occurrence and distribution of 27 per- and polyfluoroalkyl substances (PFAS) in surface water and sediment of the Fuchun River, a tributary of the Qiantang River Basin. Surface water samples were analyzed using ultra-performance liquid chromatography coupled with high-resolution mass spectrometry. Total PFAS concentrations (∑PFAS) in surface water ranged from 30.04 to 105.26 ng/L, with mean and median values of 59.64 ng/L and 51.43 ng/L, respectively. The dominant compounds were perfluorooctanoic acid (PFOA), hexafluoropropylene oxide dimer acid (GenX), and perfluorobutanoic acid (PFBA). Concentrations generally decreased from upstream to downstream, consistent with previous studies. Notably, GenX levels were significantly elevated compared to earlier reports. In sediment, ∑PFAS concentrations ranged from not detected (ND) to 0.59 ng/g dry weight, with mean and median values of 0.14 ng/g and 0.11 ng/g, respectively. PFOA and perfluorooctanesulfonic acid (PFOS) were the primary sediment contaminants. Source apportionment indicated that industrial wastewater discharge and sewage treatment plant effluents were the main sources of PFAS in the river. Risk assessment using risk quotients suggested low ecological risks to aquatic organisms for most detected PFAS. However, the presence of short-chain and novel PFAS warrants further investigation due to potential unknown risks.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025112603
The cycloaddition of carbon dioxide (CO2) to epoxides (CCE) is a 100% atom-economical transformation yielding cyclic carbonates, which are valuable chemical products. This reaction valorizes CO2 as a carbon feedstock, mitigating the greenhouse effect and aligning with carbon neutrality goals. Conventional covalent organic framework (COF) catalysts often require co-catalysts to achieve high efficiency. To address this, we designed and prepared a series of ionic COFs, denoted EB-BT(nOH), that simultaneously incorporate acid (hydroxyl), base (nitrogen), and nucleophilic bromide (Br−) functionalities. These materials efficiently catalyze the CCE reaction without any co-catalyst. Among them, EB-BT(OH) exhibited the highest catalytic activity, achieving a 99% yield of the target product at 120 °C and 2.0 MPa CO2 pressure. By systematically varying the hydroxyl content in the COF backbone, we investigated the critical role of hydrogen bond donors (HBDs) in the CCE reaction. This work provides new design principles for COF-based catalysts for CCE, eliminating the need for co-catalysts and enhancing process sustainability.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025030302
A novel core-shell composite adsorbent, C18-SiO2@C, was synthesized for the determination of five phthalates in food samples. The adsorbent was prepared by assembling hexamethylcyclotrisiloxane (D3) into γ-cyclodextrin (γ-CD) cavities via saturated solution method, followed by hydrothermal oxidation to form SiO2@C, and subsequent C18 modification on the inner SiO2 core. The outer hydrophilic amorphous carbon shell enables effective extraction, while the inner C18 layer provides hydrophobic interactions. Using tip-based solid-phase microextraction (SPME), the adsorbent (10 mg) efficiently enriched phthalates from water, milk, and cola. Under optimized conditions (pH, eluent type/volume, sample volume, salt concentration), the method coupled with GC/MS exhibited linearity in the range of 0.5–10 ng·mL−1 (R² > 0.99), limits of detection (S/N ≥ 3) of 0.04–0.15 μg·L−1, and spiked recoveries of 74%–100% (RSD 1.32%–3.49%). For real samples, recoveries were 84.6%–102.3% for tap water, 80.7%–104.6% for cola, and 80.2%–101.4% for milk. The method offers simplicity, rapidity, low sample consumption, high enrichment efficiency, and strong matrix interference resistance, demonstrating significant potential for trace phthalate monitoring in foods.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025021401
This study investigated the occurrence, distribution, sources, and ecological risks of 19 organophosphate triesters (OPEs) and 8 diesters (di-OPEs) in surface water and sediments from the Hangzhou section of the Qiantang River. Samples were analyzed using liquid chromatography-high resolution mass spectrometry. Concentrations of ΣOPEs in water ranged from 31.5 to 98.9 ng/L, and in sediments from 10.8 to 341 ng/g dry weight (dw). Σdi-OPEs ranged from 2.19 to 104 ng/L in water and 0.437 to 106 ng/g dw in sediments, indicating moderate to low contamination. TCIPP and TCEP dominated OPEs in water, while TEHP was the predominant OPE in sediments. DBP was the major di-OPE in water, and DPHP in sediments. Source apportionment via correlation and principal component analysis identified industrial production and human activities, including household, tire, plastic manufacturing, and agricultural practices, as primary sources. Ecological risk assessment revealed negligible risks for most OPEs in water, but notable risks in sediments: TEHP and EHDPP posed risks to crustaceans, and TPHP to algae. Moreover, combined toxicity at multiple sediment sampling sites raised concern, warranting further attention.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025030404
The photoelectrocatalytic degradation of seven sulfonamide antibiotics—sulfathiazole (STZ), sulfadiazine (SDZ), sulfisoxazole (SIA), sulfamethoxazole (SMZ), sulfapyridine (SPD), sulfadimidine (SMT), and sulfaguanidine (SG)—was investigated using a bismuth vanadate-loaded titanium dioxide array (BiVO4/TiO2) as the anode under visible light irradiation. Systematic evaluation of BiVO4 loading, solution pH, current density, electrolyte type, and electrolyte concentration revealed optimal conditions of 50 mmol·L−1 Na2SO4, a current density of 1.67 mA·cm−2, and pH 2. Under these conditions, STZ removal and total organic carbon (TOC) removal reached 95.7% and 76.7%, respectively. Removal efficiencies for SDZ, SIA, SMZ, SPD, SMT, and SG were 94.9%, 80.9%, 79.1%, 57.7%, 52.3%, and 52.0%, with TOC removal ranging from 50% to 76.7%. Quenching experiments and electron paramagnetic resonance (EPR) identified hydroxyl radicals (·OH), singlet oxygen (1O2), and sulfate radicals (SO4−·) as dominant reactive species. The BiVO4/TiO2 composite exhibited a valence band edge at EVB = 2.775 V vs. RHE, enabling oxidation of H2O, OH−, and SO4^2− to generate these radicals. The heterostructure narrowed the bandgap to 2.12 eV and enhanced visible light response, facilitating efficient charge separation and transfer. Degradation pathways involved oxidation of aniline moieties to nitro groups, followed by hydroxylation and cleavage of S–N, N–C, or S–C bonds, ultimately mineralizing to CO2, H2O, SO4^2−, and NO3−. The system demonstrated high stability and catalytic efficiency across acidic and alkaline conditions, offering a promising approach for antibiotic removal from environmental waters.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025031302
Trifluoropropylmethylsiloxanes (D3F and D4F) are emerging contaminants whose environmental behavior remains poorly understood. This study investigated their occurrence, bioaccumulation, and elimination in sediments and mollusks collected from 60 sites across 12 coastal cities along Bohai Bay, China. Concentrations in sediments ranged from <LOD to 17.1 ng/g dry weight (dw) with a detection frequency of 30% and a mean of 5.6 ng/g dw. In mollusks, concentrations ranged from <LOD to 20.2 ng/g wet weight (ww) with a detection frequency of 21.7% and a mean of 4.1 ng/g ww. Compared with cyclic dimethylsiloxanes (D4, D5, D6), trifluoropropylmethylsiloxanes exhibited 1–2 orders of magnitude lower concentrations and 1.4–2.2 times lower biota-sediment accumulation factors (BSAF: 0.67 for D3F, 0.61 for D4F). However, from 2017 to 2023, trifluoropropylmethylsiloxanes showed higher annual accumulation rates in sediments (21.5%) and mollusks (32.8%) than dimethylsiloxanes (10.2% and 6.7%, respectively). This discrepancy is attributed to their higher usage growth, stronger sorption (lg KOC: 6.77 for D3F, 8.81 for D4F vs. 4.22–5.99 for D4–D6), and slower elimination in mollusks (half-lives: 11.1 d for D3F, 20.1 d for trans-D4Fa vs. 5.4–8.6 d for D4–D6). The primary degradation product, methyl(3,3,3-trifluoropropyl)silanediol, was detected in sediments (mean 15.7 ng/g dw, detection frequency 33.3%) and mollusks (mean 31.2 ng/g ww, detection frequency 33.3%). Its accumulation rate in mollusks was 1.4 times faster than in sediments, suggesting its potential as an exposure indicator. These findings highlight distinct environmental behaviors of trifluoropropylmethylsiloxanes, necessitating further monitoring and risk assessment.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025042101
Chloropyridine compounds, widely used as pesticide intermediates in China, pose significant risks to aquatic ecosystems and human health due to their high toxicity, persistence, and frequent detection in water bodies. This study addresses the removal of 3,4,5,6-tetrachloropyridine-2-carboxylic acid (TCPA), a representative chloropyridine contaminant, using a novel composite material. Biochar-supported zero-valent iron/iron carbide composites (SL-FeC2O4-800 °C) were synthesized via a high-temperature carbothermal process, employing activated sludge as the carbon source and ferrous oxalate (FeC2O4) as the iron precursor. The composite exhibited rapid and efficient TCPA degradation across a wide pH range (3–9), achieving 98% removal within 2 minutes. Mechanistic studies using scavenging experiments revealed that TCPA removal proceeds through synergistic pathways: adsorption onto biochar, direct reduction by zero-valent iron, and oxidation by reactive oxygen species (ROS) generated via oxygen activation. Surface-bound iron species were identified as critical for ROS formation. The material demonstrated reusability over five cycles, with degradation efficiencies decreasing from 98.54% to 40.36%, indicating gradual deactivation due to iron consumption and surface passivation. This work not only provides an efficient and environmentally sustainable method for removing persistent and highly toxic pollutants like TCPA but also offers a novel strategy for sludge resource utilization. The low-cost raw materials, simple preparation, and high activity position this composite as a promising candidate for industrial wastewater treatment, particularly in pesticide manufacturing effluents.