环境科学与技术最新文献

Here, we present a novel micro Total Analysis System (μTAS) for the measurement of poly cyclic aromatic hydrocarbon (PAH) and other aromatic hydrocarbons (AHs) in water at ng/L levels in situ and in real time (IMiRO). The μTAS is based on in-line membrane extraction followed by detection of extracted aromatic substances with fluorescence. An offshore field demonstration of the method was conducted close to produced water (PW) discharged in the North Sea. PW was monitored with the IMiRO μTAS and compared to results from a simultaneously conducted independent tracer release experiment, where fluorescein was added to the PW as a tracer. The μTAS monitoring and fluorescein tracer experiment showed similar ability to track the dispersion of the PW plume in space, depth, and time. Moreover, the method detected the sum of phenanthrenes and the sum of heavier PAHs with limits of detection down to 6 ng/L, with a response time of 6 min. The novel μTAS system opens up for in situ real-time discharge monitoring of both permitted and accidental oil or PW releases from oil platforms as well as other sources. Such monitoring can also be used to test and verify dispersion models used for environmental risk assessment.

Advanced oxidation processes (AOPs) based on peracetic acid (PAA) offer a promising strategy to address antibiotic wastewater pollution. In this study, Fe-doped graphitic carbon nitride (g-C₃N₄) nanomaterials were used to construct Fe-N_x sites, and the electronic structure was tuned by boron nitride quantum dots (BNQDs), thereby optimizing PAA activation for the degradation of antibiotics. The BNQDs-modified Fe-doped g-C₃N₄ catalyst (BNQDs-FCN) achieved an excellent reaction rate constant of 0.0843 min^-1, marking a 21.6-fold improvement over the carbon nitride (CN)-based PAA system. DFT calculations further corroborate the superior adsorption capacity of the Fe-N_x sites for PAA, facilitating its activation. Charge transfer mechanisms, with PAA serving as an electron acceptor, were identified as the source of high-valent iron-oxo species. Moreover, the BNQDs-FCN system preferentially targets oxygen-containing functional groups in antibiotic structures, elucidating the selective attack patterns of these highly electrophilic species. This research not only elucidates the pivotal role of high-valent iron-oxo species in pollutant degradation within the PAA-AOPs framework but also pioneers a wastewater treatment system characterized by excellent degradation efficiency coupled with low ecological risk, thereby laying the groundwork for applications in wastewater management and beyond.

Biomass burning organic aerosol (BBOA) is a major contributor to organic aerosol in the atmosphere. The impacts of BBOA on climate and health depend strongly upon their physicochemical properties, including viscosity and phase behavior (number and types of phases); these properties are not yet fully characterized. We collected BBOA field samples during the 2021 British Columbia wildfire season to constrain the viscosity and phase behavior at a range of relative humidities and compared them to previous studies on BBOA. Particles from all samples exhibited two-phased behavior with a polar hydrophilic phase and a nonpolar hydrophobic phase. We used the poke-flow viscosity technique to estimate the viscosity of the particles. Both phases of the BBOA had viscosities of >10⁸ Pa s at relative humidities up to 50%. Such high viscosities correspond to mixing times within 200 nm BBOA particles of >5 h. Two phases and high viscosity have implications for how BBOA should be treated in atmospheric models.

Disinfection byproducts (DBPs) in swimming pool water are a significant public health concern. The formation of aromatic halogenated DBPs in swimming pool water has not been clarified previously. In this study, the occurrence of aromatic halogenated DBPs in swimming pool water was examined, and it was found that halohydroxybenzoic acids (HBAs) and halobenzoquinones (HBQs) were the most dominant aromatic halogenated DBPs in swimming pool water that were continuously formed. Thus, the formation of HBAs and HBQs in swimming pool water from different organic precursors, including natural organic matter (NOM), pharmaceuticals and personal care products (PPCPs), during chlorination was examined. The results demonstrate that the formation of HBAs and HBQs from the PPCPs was relatively high compared with that from NOM, suggesting that the PPCPs from human inputs might be important organic precursors of aromatic halogenated DBPs in swimming pool water. The formation mechanisms of HBAs and HBQs from three typical PPCPs (benzophenone-3 (BP-3), methyl p-hydroxybenzoate (MeP) and carbamazepine) were further explored. The results show that the PPCPs containing phenolic groups with higher degradation rates (BP-3 and MeP) possessed higher formation of HBAs and HBQs. The three organic precursors underwent a series of substitution, hydrolysis, oxidation, rearrangement, and intramolecular cyclization reactions to form HBAs and HBQs, while the phenolic groups and ring structures may significantly affect the reactions. The chlorine dose, bromide/iodide concentration, and temperature significantly affected the formation of HBAs and HBQs from MeP during chlorination.