Environmental Science & Technology Letters Environ.最新文献

Differences in height-dependent near-ground air pollutant concentrations have not received sufficient attention in air quality monitoring and exposure measurement, of which the ignore could introduce significant bias in exposure assessment for people with different heights. Here, a modified passive air sampler was developed and used to characterize vertical profiles of typical hazardous polycyclic aromatic compounds (PACs) in near-ground microenvironments. Field measurements demonstrated significant vertical changes for most target air pollutants within the 2–150 cm height range, with the relative difference ranging from 1.1 to 40.0. The concentration of total PACs generally showed an increasing trend with height; however, the intensity of this vertical variation was closely linked to season, pollution levels, and photochemical activity, and it also varies among individual compounds. Children’s exposure to total BaP_eq would be significantly overestimated, particularly during summer, with the overestimation ranging from 13% to 79%. This vertical heterogeneity implies that exposure assessment should not overlook the height-dependent variability of near-ground air pollution levels, and the sampling strategy employed in this study can be used to evaluate the vertical variation of air pollutants across different microenvironments.

The high regeneration energy consumption of amine-based carbon capture represents a critical bottleneck hindering the large-scale implementation of CCUS technologies. To overcome the proton transfer limitations inherent in conventional thermal regeneration, which relies on elevated temperatures, this study proposes a novel homogeneous catalytic system utilizing proton shuttles. By replacement of heterogeneous solid acid catalysts with small organic molecules (e.g., ethanol), this system enables efficient proton transfer while circumventing solid–liquid interfacial diffusion resistance. The dynamic proton exchange capability of these shuttles, operating BH/B^– cycling, accelerates the deprotonation of RNHCOO^– species and significantly reduces the reaction energy barrier. Experimental results demonstrate that ethanol, because its pK_a value balances proton donation and acceptance capabilities, reduces regeneration energy consumption by 35%, with isotope-labeled mass spectrometry confirming the proton transfer pathway. This homogeneous catalytic mechanism, through molecular-level optimization of proton transfer dynamics, provides a new pathway for developing efficient and stable CO₂ desorption processes, potentially accelerating the economic advancement of carbon capture technologies toward achieving carbon neutrality goals.

N-Nitrosodimethylamine (NDMA) is a probable human carcinogen that has attracted increasing concern, owing to its occurrence in various consumer products. We aimed to determine the amount of NDMA contained in various types of rubber gloves and its behavior. It was found that rubber gloves contained NDMA exceeding 2 mg/kg, which volatilizes into the air during storage, causing air contamination and easily dissolving in water when used. Thus, the exposure risks of NDMA contained in rubber products may be underestimated. A temperature-dependent leaching experiment demonstrated that NDMA leaches more rapidly from gloves at higher temperatures. Furthermore, exposure to ambient air decreased NDMA content over time, indicating loss by volatilization. These findings suggest that NDMA levels in gloves may be highest at the time of manufacture and can fluctuate depending on storage conditions, thus highlighting the potential for underestimated health risks. Our results provide important new insights into the safety assessment of disposable rubber gloves and underscore the need for further evaluation and regulation of NDMA in these products.

Microbial electrolysis cells (MECs) offer a novel alternative to conventional biological ammonium (NH₄⁺) removal by using electrodes rather than oxygen as electron acceptors. However, NH₄⁺ oxidation at bioanodes can result in substantial nitrous oxide (N₂O) emissions─a potent greenhouse gas with significant climate impact. We investigated the potential of hydrogenotrophic denitrification within the anodic compartment to mitigate N₂O emissions during NH₄⁺ removal. In situ hydrogen (H₂) addition effectively reduced N₂O concentrations to below 0.01 mg of N/L, without nitrate or nitrite accumulation. Batch experiments demonstrated that the suspended biomass exhibited a high capacity for N₂O reduction, which was strongly dependent on H₂ availability and linked to denitrification activities. Integrating hydrogenotrophic denitrification with NH₄⁺ oxidation in MECs presents a promising approach for sustainable nitrogen management with near-zero N₂O emission.

Reducing global methane emissions is vital in combating climate change. Satellite-based instruments provide a way to independently monitor methane emissions from various sources at different scales, helping to assess the progress toward emission reduction targets. In this paper, we apply several data-driven methods to estimate methane emissions from the Secunda CTL (coal-to-liquids) synthetic fuel plant in South Africa, utilizing satellite observations from the TROPOspheric Monitoring Instrument (TROPOMI) aboard the Sentinel-5 Precursor (S5P) satellite and the GHGSat fleet of high-resolution commercial satellites. We find annual mean emissions of about 13–22 t/h based on S5P/TROPOMI observations. These results are consistent with estimates from an automated TROPOMI methane plume detection and quantification method. Estimates based on GHGSat observations from individual sources within the plant sum to about 6 t/h, on average. For comparison, Sasol, the operator of the Secunda CTL facility, reported methane emissions of 11.5 t/h for the period July 2023–June 2024, a value that falls between the TROPOMI- and GHGSat-based estimates. Our results highlight the value of satellite observations as a useful audit complementing reported emissions and demonstrate the importance of combining coarse- and fine-resolution data to monitor methane emissions at the plant and intrafacility level in complex sources.

Plastic pollution is rising, widespread, and a threat to biodiversity. Understanding the drivers of plastic ingestion is the key to developing a risk assessment. Although plastic availability, plastic–prey resemblance, degree of food selectivity, and the nutritional state of organisms have been identified as the four main drivers of plastic ingestion, we are still building an evidence base to support these drivers. To strengthen our knowledge of the drivers of plastic ingestion, we used two approaches: a systematic literature review and controlled experiments. Both approaches corroborated these factors as drivers of plastic ingestion, but despite these advances, studies are still needed that address holistic questions applicable to broader scenarios rather than focusing solely on taxon-specific traits or plastic characteristics in isolation from their ecological context. Additionally, a new driver has emerged─the social environment─which adds further complexity to how group formation may affect plastic ingestion across species.

The Tamarack ultramafic intrusion in Minnesota, USA, may be suited to host concurrent CO₂ injection and critical mineral recovery. These dual capabilities are vital to manage emissions and supply metals (e.g., nickel) necessary for rapidly upscaling energy and data technologies. To understand subsurface carbonation reaction pathways and assess mineralization potential in the Tamarack Intrusive Complex (TIC), we reacted a suite of Tamarack Bowl intrusion olivine (BIO) samples with aqueous-dissolved and liquid or supercritical CO₂ (scCO₂) at 90 bar and 21–90 °C. Samples were characterized pre- and postreaction with multiple geochemical and mineralogical techniques, and results indicate mineral dissolution followed by magnesite precipitation. Pseudo in situ Identical Location Transmission Electron Microscopy (IL-TEM) experiments revealed that a carbonation reaction of TIC BIO peridotite with water-saturated scCO₂ formed aragonite nanocrystals on an altered plagioclase surface and induced dissolution of nickel-bearing forsteritic olivine. The presence of nanoscale-resolved carbonation products identified by IL-TEM, coupled with carbonate transformation rates quantified in batch reactions, suggests that the TIC BIO resource can conservatively store 320–1,070 million metric tonnes (MMT) of CO₂ via mineralization while mobilizing 0.9–3.1 MMT of nickel if only 5% of the TIC rock volume is accessed.

Chloronitramide anion (Cl–N–NO₂^–) is a recently discovered inorganic chloramine decomposition product, with prior quantitation by hydrophilic interaction liquid chromatography–ultrahigh-resolution mass spectrometry (HILIC–UHRMS). Here, Cl–N–NO₂^– quantitation was evaluated by ion chromatography (IC) separation with electrical conductivity (EC) and ultraviolet absorbance at 243 nm (UV₂₄₃) detection. Using a 5 mL injection loop and a 14.4 mM Na₂CO₃ eluent, the Cl–N–NO₂^– method detection limit was 9.3 μg L^–1 by IC-EC and 6.2 μg L^–1 by IC-UV₂₄₃. Matrix testing with Cl–N–NO₂^– spiked at 15, 25, 50, and 100 μg L^–1 into 12 waters in triplicate matched the expected Cl–N–NO₂^– for IC-EC (R² = 0.994) and IC-UV₂₄₃ (R² = 0.993). Cl–N–NO₂^– was found by HILIC–UHRMS in all tested tap waters disinfected with chloramines (n = 8) at 22–314 μg L^–1 and free chlorine (n = 3) at 2–7 μg L^–1, and strongly correlated with IC-EC (R² = 0.991; average residual, $\overline{r_i}$ = +3.2 μg L^–1) and IC-UV₂₄₃ (R² = 0.997; $\overline{r_i}$ = 0.0 μg L^–1). This is the first report of Cl–N–NO₂^– in free chlorine systems and concentrations ≳200 μg L^–1 in chloramine systems. These IC methods enable widescale collection of Cl–N–NO₂^– occurrence data, with IC-UV₂₄₃ subject to lesser measurement bias.

The removal of heavy-metal complexes (HMCs) from industrial wastewater remains challenging due to their stability and resistance to conventional methods. Here we reveal the critical yet overlooked roles of the adsorbent/adsorbate interfacial dynamics and nanoconfinement effects in governing HMC removal. Using UiO-66(Zr), a zirconium-based metal–organic framework (MOF), we demonstrate that interfacial proton transfer induces rapid acidification, decomplexing Cu(II)–carboxyl species into free copper ions and ligands. Nanoconfinement within UiO-66(Zr) octahedral cavities promotes ligand deprotonation and selective adsorption, while further released copper ions are precipitated via alkali treatment. This synergy achieves over 99.95% Cu removal, surpassing standalone methods. Fixed-bed column experiments validated its practicality, producing 1828 bed volumes of compliant water (<0.3 mg Cu/L) and enabling Cu recovery, outperforming individual components by 6–208-fold. Density functional theory calculations confirm stronger MOF interactions with deprotonated ligands than complexes, driven by electrostatic and Lewis acid–base interactions. This work highlights the mechanistic understanding of HMC removal by bridging dynamic interfacial processes and nanoconfinement-driven reaction pathways, offering a cost-effective, scalable solution for metal recovery as well.

To address knowledge gaps in microplastic (MP) fates within connected ecosystems, this study analyzes divergence and convergence across interconnected seagrass and coral habitats. Convergence was limited: Only 16% of MP categories were shared (notably black fibrous PET), and high-density MPs consistently accumulated in sediments in both ecosystems. However, divergence was pronounced. Seagrass meadows acted as selective filters that facilitated sedimentation of larger MPs, leaving smaller fractions to dominate transport to reefs, where they accumulated on coral surfaces and tissues. Notably, biological selectivity altered this pattern internally: while small MPs were prevalent, coral tissues disproportionately accumulated large (1–2 mm), high-density transparent fibers, likely triggered by physical entanglement and prey-mimicking optical cues. Seagrass leaves intercepted high-density MPs on surfaces, whereas corals were highly susceptible to internal accumulation within tissues and skeletons. Furthermore, coral skeletons served as long-term archives sequestering diverse, predominantly high-density MPs, while seagrass leaves acted as short-term dynamic traps with significantly higher surface abundance. Specifically, surface accumulation was morphologically driven, whereas internal incorporation in corals was biologically regulated and decoupled from surface loads. Mechanistically, these patterns suggest that intrinsic biological modulation is the primary driver of MP heterogeneity between ecosystems. These findings highlight the need for habitat-specific risk assessments.