ACS Environmental Au最新文献

This study focuses on the development of environmentally friendly double enzyme catalysts for the degradation of organic pollutants in water, addressing key environmental concerns. The hybrid tandem system of xanthine oxidase (XO) with horseradish peroxidase (HRP) is designed for sustainable water treatment by using a natural and eco-friendly silicate substrate, perlite, as a support for the enzyme cascade reaction. The catalytic process was optimized for environmental applications. XO-generated hydrogen peroxide through the oxidation of hypoxanthine, which then activated HRP to break down a variety of harmful pollutants, including industrial dyes, pharmaceuticals, and phenolic compounds. The system demonstrated high pollutant removal efficiency, reaching up to 100% in some cases, while maintaining catalytic stability across a range of temperatures and pH values. Importantly, the biocatalytic system addressed secondary pollution─a common issue in conventional treatments. Thus, uric acid, a potential byproduct of the XO catalytic action, was degraded by HRP, preventing the accumulation of harmful byproducts in purified water. This research highlights the potential of the tandem XO-HRP enzyme cascade as a green, efficient, and sustainable solution for water purification, offering an environmentally responsible alternative to traditional methods that often contribute to further contamination.

Disposal of food waste (FW) in landfills remains an unsustainable practice for organic waste management. Simultaneously, pulp and paper mills produce significant amounts of recalcitrant organic waste that is difficult to decompose due to its high lignocellulosic content. In this study, we developed an innovative approach to improve the digestion of pulp and paper mill sludge (PPMS) by amending FW to produce a low chemical oxygen demand (COD) sludge while recovering methane in the process. This codigestion process was evaluated through lab-scale biogas production experiments coupled with a comprehensive economic and environmental sustainability assessment. Biomethane production results revealed that the FW-PPMS codigestion methane yield was 36% higher on average than the PPMS monodigestion. Additionally, metagenomic analysis revealed that microbial communities for both systems transitioned from highly heterogeneous to more adapted uniform communities after digestion. Improved microbial communities contributed to higher COD removal (92%) in the FW-PPMS system compared to monodigestion (80% removal). The sustainability analysis revealed that the codigestion of FW-PPMS had median costs of 236.64 USD·tonne^–1·day^–1 and emissions of 228.30 kg CO₂ eq·tonne^–1·day^–1, a significant reduction compared to directly disposing the FW in landfills (median costs of 405.13 USD·tonne^–1·day^–1 and emissions of 556.27 kg CO₂ eq·tonne^–1·day^–1). A nationwide contextual analysis revealed that out of six regions, the US Northeast had the lowest median costs and emissions, while the Mountain Plains region had the highest, highlighting the importance of geographical and infrastructural factors in implementation. Overall, codigesting FW with PPMS is revealed to be a sustainable waste management option to decrease landfill disposal of valuable organic waste.

Reactions between skin oil and ozone are a substantial source of volatile organic compounds (VOCs) emitted from the human body, yet factors influencing these reactions and emissions have only recently begun to be investigated. In this study, we conducted single-person chamber experiments involving three volunteers to systematically assess the influence of various factors, including temperature, relative humidity (RH), personal hygiene (bathing frequency and clothing soiling), and clothing coverage. We found that chamber air temperature and RH, within the range of 22–31 °C and 40–70% respectively, had negligible effects on ozone-driven VOC emissions, likely due to the body’s regulation of its surface temperature and humidity. This finding contrasts with the pronounced RH dependence reported for ozone reaction with skin oil constituents or skin-oil-soiled materials in the absence of such surface regulation. Refraining from changing clothes for 3 days increased the total emissions of key products by ∼25%, while refraining from showering for 3 days showed minimal effect, likely because skin oil on body surfaces rapidly re-equilibrates. In addition, compared with wearing freshly laundered t-shirts and shorts, wearing clothing that covered more of the body decreased the summed surface yield by nearly 50%. These findings provide new insights into skin oil chemistry adjacent to the body, highlighting the body’s role in regulating the surface environment where exogenous chemistry occurs. The results suggest that a simple model that does not account for variations in bathing frequency, indoor air temperature, and humidity, might be sufficient to describe ozone-dependent dermal emission of VOCs.

This study investigated the feasibility of foam-enhanced air sparging (FEAS) for remediating trichloroethylene (TCE) dense nonaqueous phase liquid (DNAPL) in water. Various surfactants, including polyoxyethylene (20) sorbitan monooleate (TW80), sodium dodecyl sulfate (SDS), sodium α-olefin sulfonate (AOS), and TW80/SDS and TW80/AOS combinations, were used to generate foam, which were evaluated for foam stability and quality. AOS (32 mM) exhibited the highest foam stability (∼345 min) and quality (∼99.6%) under controlled conditions. Phase contrast microscopy analysis showed foam sizes of 290–400 μm with thin film thicknesses of 6–9 μm. FEAS was tested with and without sodium persulfate (SPS) oxidant (oxidative foam) to treat approximately 10 g of TCE DNAPL in 1 L of water. Injecting AOS foam (32 mM) or oxidative foam AOS (32 mM)/SPS (50 or 1700 mM) for 2 h dissolved 60–82% of TCE, compared to only 4–7% with N₂ injection. The surfactant-stabilized interface in foam facilitated TCE adsorption, increasing its partitioning into bubbles, leading to enhanced volatilization. In the lamella region, surfactant layers promoted TCE dissolution, while SPS aided its mineralization. With oxidative foam at a higher SPS concentration (1700 mM) and an extended reaction time (240 h), TCE mineralization increased to 40–74% across different foam injection rates. These results highlight oxidative FEAS as a promising improvement over conventional air sparging, significantly enhancing TCE dissolution, volatilization, and oxidation.

Double-stranded RNA (dsRNA)-based biopesticides represent promising tools for target-oriented pest and pathogen control. However, their compatibility with beneficial organisms used in biological control programs is not clear. In this study, the potential interactions between two dsRNA formulations─naked and minicell-encapsulated (ME-dsRNA)─and different commercialized bacterial, fungal, and insect biocontrol agents (BCAs) were examined. There was no toxicity of either of the two dsRNA formulations toward Bacillus amyloliquefaciens, Trichoderma harzianum, or Ulocladium oudemansii, based on growth assays. ME-dsRNA significantly enhanced fungal BCA growth, likely due to improved uptake or protection. Coapplication trials on strawberry fruit and foliage showed that coapplication of dsRNA and BCAs was efficacious with no evidence of synergistic or antagonistic effects. Insect bioassays demonstrated that dsRNA sprays had no adverse effects on predatory mite populations (Amblyseius swirskii and Phytoseiulus persimilis). Additionally, in silico off-target analysis detected minimal potential matches in T. harzianum and Tetranychus urticae, none of which corresponded to in vivo toxicity. Markedly, greenhouse and in vitro assays confirmed that neither dsRNA formulation interfered with the biocontrol efficacy of BCAs on Botrytis cinerea in strawberry. Overall, this study provides strong evidence that dsRNA-based products, including ME-dsRNA, are compatible with key BCAs and pose minimal ecological risk.