Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025091203
The persistence of tetracycline (TC) in aquatic environments poses significant ecological risks. This study developed a homogeneous reaction system based on carboxylated Fe2+ enhanced peroxymonosulfate (PMS) activation, using citric acid (CA) as a ligand. Carboxylation improved Fe2+ stability and catalytic activity, while solid PMS served as the oxidant, circumventing issues of traditional Fenton processes such as H2O2 instability, complex heterogeneous catalyst preparation, high disposal costs, and toxic metal leaching. The acidic pretreatment enabled by CA inhibited Fe2+ oxidation and promoted sustained PMS activation without external energy input. Under optimized conditions (TC 5 mg·L−1, Fe2+ 0.02 mmol·L−1, CA 0.001 mmol·L−1, PMS 2 mmol·L−1), 88.80% TC degradation was achieved within 60 min. Mechanistic studies revealed that CA protected Fe2+ active sites via carboxyl coordination, facilitating continuous generation of reactive species, including singlet oxygen (1O2) and sulfate radicals (SO4•−). 1O2 was the dominant species (50.5% contribution), followed by SO4•− (35.7%), synergistically driving efficient TC degradation while significantly reducing iron sludge production. Phytotoxicity assays confirmed that treated water exhibited no significant toxicity to wheat seedlings (P > 0.05), indicating effective ecological risk elimination. This work provides a low-energy, operationally simple, and environmentally friendly technology for antibiotic-contaminated water treatment, with promising practical application potential.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202604016
River and lake health assessment is an important technical means to evaluate the health status of rivers and lakes, scientifically analyze river and lake problems, and strengthen the implementation of the river and lake head system. Based on the Guidelines for River and Lake Health Assessment (Trial) and the characteristics and actual basin conditions of the lower Yellow River in Henan, this study determined the river health evaluation index system for this reach. Through collection of basic data and special investigations and monitoring, the health status in 2020 was evaluated from four criteria layers: 'basin', 'water', biology, and social service function. The overall score was 83.4, corresponding to a 'healthy' grade. The four criteria layer scores were 73.7, 95.0, 62.1, and 95.5, respectively. The evaluation identified main problems including low aquatic biodiversity, suboptimal shoreline conditions, and pressure on water supply security. Corresponding governance and protection measures were proposed, such as strengthening ecological protection, improving river regulation works, enhancing shoreline management, and upgrading water diversion facilities. The results provide scientific basis for river health management and the implementation of the river chief system in the lower Yellow River.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2026020207
Although the production and use of hexabromocyclododecanes (HBCDs) have been completely banned in China since December 2021, historical production activities may still leave high-concentration residual contamination in localized areas. This study investigated a typical legacy site of historical HBCDs production in eastern China. Surface and core soil samples were systematically collected both inside and outside the former plant area to characterize the occurrence, spatial distribution, and environmental burden of HBCDs, and to evaluate associated human health risks. Results showed that HBCD concentrations in soils outside the plant area ranged from below detection limit to 6.90×10² ng·g⁻¹ dw, while those inside the plant area were substantially higher, reaching up to 1.18×10⁶ ng·g⁻¹ dw. γ-HBCD was the dominant isomer; however, its relative abundance was lower than that reported in commercial HBCD mixtures and in previous studies conducted near production facilities. Outside the plant, HBCDs concentrations in soil generally decreased with increasing distance from the site, yet remained detectable at a distance of approximately 10 km (15.2 ng·g⁻¹ dw). Within the plant area, HBCDs concentrations in soil cores decreased with depth, declining from 1.08×10⁴–1.18×10⁶ ng·g⁻¹ dw in surface soils to 1.05–93.5 ng·g⁻¹ dw at depths of about 4 m. Analysis of the relative cumulative environmental burden indicated that although HBCDs loads were highest in the near-source area, they gradually accumulated over a broader spatial scale. Approximately 23.7%, 40.1%, 60.0%, and 87.1% of the total estimated burden accumulated within 2 km, 2.81 km, 4 km, and 6 km from the site, respectively. Health risk assessment indicated that oral ingestion of soil was the primary exposure pathway for different populations. Localized high-contamination zones within the plant area contributed significantly to non-carcinogenic risks, while overall risks for children outside the plant area were at acceptable levels.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4109-2
The fabrication of high-efficiency organic solar cells (OSCs) under ambient conditions remains a formidable challenge due to the sensitivity of active layer morphology to environmental factors. We propose an innovative approach for air-processed devices that combines spontaneous water-spreading film formation with layer-by-layer (LBL) deposition. This method enables the fabrication of donor- and acceptor-dominant bulk heterojunction blend films near the anode and cathode interfacial layers, respectively, optimizing vertical phase separation and enhancing charge transfer efficiency. In the D18:L8-BO system, the device achieves a power conversion efficiency (PCE) of 19.02% with an exceptionally narrow efficiency distribution. Even for devices with an area of 1 cm2, a PCE of 16.56% is attained. After a 1000-hour decay test, the efficiency retains 84.1%. This novel method offers a promising pathway for advancing the industrial application of large-area, highly stable devices with narrow efficiency distribution under ambient conditions.