Environmental science. Advances最新文献

Many per- and polyfluoroalkyl substances (PFAS) are known to be persistent in the environment and are associated with adverse health effects including kidney and liver disease and developmental toxicity. While PFAS are also known to have high bioaccumulation potential, whether these compounds can be detected in biological tissue using nuclear magnetic resonance (NMR) has not been established. In this study, we used ¹⁹F solid-state magic angle spinning (MAS) NMR to investigate the accumulation of a legacy PFAS, perfluorooctanoic acid (PFOA), in murine tissue samples including the adult brain, intestine, kidney, liver, uterus, adipose tissue, placenta and fetal brain. Healthy pregnant (n = 4) and non-pregnant (n = 5) female CD-1 mice were exposed to 50 ppm of PFOA through their drinking water for 17 days. PFOA was detected above the limit of detection (10 μg g⁻¹) in all of the liver samples (n = 9/9), 25% (n = 2/8) of the adipose tissue samples, 33.3% (n = 4/12) of the male placenta samples, and 16.7% (n = 2/12) of the female placenta samples. The detection of PFOA in adipose tissue challenges the current understanding about the behaviour of PFAS in the human body. These results demonstrate that ¹⁹F solid-state MAS NMR is a promising tool for detection and quantification of PFAS in tissue samples and motivate further work to evaluate accumulation of unregulated, emerging PFAS that have different chain lengths and head groups.

Correction for ‘Microbial degradation of bioplastic (PHBV) is limited by nutrient availability at high microplastic loadings’ by Michaela K. Reay et al., Environ. Sci.: Adv., 2025, 4, 133–146, https://doi.org/10.1039/D4VA00311J.

Indium phosphide (InP) quantum dots (QDs) offer a sustainable, low-toxicity alternative to heavy-metal-based nanomaterials for environmental detoxification. This critical review evaluates their potential as green photocatalysts, focusing on their ability to degrade organic pollutants, including dyes, pesticides, and polycyclic aromatic hydrocarbons (PAHs), under visible-light irradiation. Innovations in ligand functionalization, core/shell architectures, and eco-friendly synthesis enhance colloidal stability, photostability, and charge separation, surpassing traditional photocatalysts such as CdSe/ZnS and TiO₂ in efficiency and safety. By elucidating structure–property relationships, this work provides a novel framework for designing scalable, biocompatible nanomaterials, paving the way for advanced nanoremediation technologies to address global pollution challenges.

Tropical dry forests (TDFs) are critical carbon reservoirs, yet their carbon storage dynamics remain poorly understood, particularly across seasons, forest subtypes, and species′ contributions. This study examined carbon pools—soil organic carbon (SOC), aboveground biomass carbon (CAGB), and litterfall carbon (C-litterfall)—across three TDF subtypes along the Ecuadorian coast. Twelve 100 m² plots were monitored semi-annually during rainy and dry seasons, with extrapolations made to assess total forest patch carbon stocks. SOC was the dominant carbon pool across all subtypes and seasons, with rainy periods contributing to greater SOC stability (LSF, 75.51 Mg ha⁻¹; LDF, 70.01 Mg ha⁻¹; SPF, 69.27 Mg ha⁻¹) compared to dry periods (LDF, 54.70 Mg ha⁻¹; LSF, 53.35 Mg ha⁻¹; SPF, 39.39 Mg ha⁻¹). CAGB and C-litterfall displayed significant seasonal variation, with litterfall peaking in the dry season, particularly in LSF (0.4 Mg ha⁻¹). Across subtypes, total carbon densities averaged 94.0 Mg ha⁻¹ in LSF, 67.4 Mg ha⁻¹ in SPF, and 99.9 Mg ha⁻¹ in LDF. Plant species significantly influenced CAGB. In LSF, T. integerrima contributed the most to CAGB (6.4–6.7 Mg ha⁻¹), while C. eggersii dominated in SPF (4.5–4.4 Mg ha⁻¹). In LDF, C. lutea was the leading contributor, storing 13.8–13.9 Mg ha⁻¹ of biomass carbon. Extrapolation to forest patches revealed substantial spatial differences, with LDF sequestering the most carbon (526 133.3 Mg), followed by SPF (463 133.0 Mg) and LSF (3113.3 Mg). These findings underscore the critical roles of species composition, climatic variability, and forest structure in carbon sequestration, emphasizing the need for tailored conservation strategies to mitigate climate change impacts.

Per- and polyfluoroalkyl substances (PFAS) have become ubiquitous surfactants in the environment with long lifetimes, and emerging toxic effects. Capture and removal of PFAS from aqueous media is an important step in the treatment train along with the concentration and destruction of PFAS. Particularly PFAS with shorter alkyl chain lengths have proven to be difficult to remove from water. As a result of partial degradation from longer PFAS's as well as their enhanced mobility in the environment, short-chain PFAS are very prolific making them a high-target focus for PFAS removal research. Using molecular dynamics simulations of functionalized graphene oxide pores, we have shown that the selectivity and capacity of adsorption media for differing tail lengths of linear PFAS are impacted by the size of the material's nanoporosity. The relationship between PFAS transport and pore size is not monotonic and different PFAS have different critical pore diameters with a minimum in transport resistance enabling an effective mechanism for PFAS specificity. More pragmatically, we have identified critical pore diameters that impact the thermodynamics and kinetics of PFAS binding and transport. For example, selectivity towards PFBA is highest in pores of 9 Å diameter. These results imply design parameters with which to tune adsorption media to different partitioning, transport, and selectivity towards different PFAS.

Over the past few decades, technical advances have been made in the destruction of chemical warfare agents (CWAs) due to an enhanced understanding of reaction chemistries. This review focuses on summarizing the deactivation of the following CWAs: sulfur mustard (HD), sarin (GB), and nerve agent X (VX). This review includes multiple aspects of the agents, including chemical and physical properties, lethal doses, and common surrogates. However, the primary focus of the review is on various thermophysical approaches to deactivate these harmful chemical agents. Conventional deactivation technologies, including incineration and neutralization, are discussed along with advanced approaches, such as wet air oxidation, catalytic, and metal–organic frameworks (MOF) treatments. The review indicates that all three agents can be destroyed to nearly 100% Destruction and Removal Efficiency (DRE) with incineration, but at a high cost and with a significant energy demand, and only at secure, established facilities. Several countries have used incineration to reduce large volumes of CWA stockpiles. Other neutralization, wet air oxidation, and supercritical oxidation technologies are demonstrated at lab and pilot-scale levels to achieve 98–100% DRE depending on the operating conditions. Other relatively new technologies, such as catalytic deactivation and treatment using MOF, can achieve 70–100% efficiency but are still in the embryonic or laboratory development stage. Deactivation of CWAs with MOFs exhibit high degradation potential, reaching 100% DRE, but it may not be suitable for large volumes. Catalyst and MOF treatment may be ideal for deactivating small-volume CWA. However, further development and demonstrations are required.

Per- and polyfluoroalkyl substances (PFAS) are a large class of industrial chemicals whose diversity, spread, and environmental/health impacts have recently become a major concern for environmental and health policy makers. This concern is further exacerbated by their pervasiveness and chemical resilience, which complicates their removal from watersheds and other contaminated environments. Due to the chemical stability of the carbon–fluoride bonds, they are difficult to degrade. Instead, an alternative presents itself in the form of adsorption, concentration, and then removal of PFAS from contaminated sites. Both metal organic frameworks (MOFs) and covalent organic frameworks (COFs) have recently come under significant investigation as possible adsorption media which could be adapted for the removal of PFAS from contaminated sites. To gain greater insight into the adsorption capabilities of COFs for the removal of PFAS from waterways, we have studied the adsorption of PFAS molecules in COFs of differing pores sizes using molecular dynamics simulations. We examine the absorption of aqueous PFBA, PFOA, and PFOS into Covalent Triazine-Based Frameworks (CTF) of different pore sizes. This mechanistic adsorption data shows that a goldilocks zone occurs in pores with diameters of around 8 Å where the PFAS thread through the pores smoothly. Kinetic factors from diffusion into these nanopores favors the adsorption of short chain PFAS even though larger PFAS are thermodynamically favored. Each pore tends to initially adsorb only one PFAS, occupying the mouth of the pore, until the local COF surface is saturated and then multiple occupancy per pore can occur. Discussion on the impacts of PFAS concentration and interaction with the pores will inform design principles for enhanced selectivity and capacity for PFAS adsorbent material.

Microplastic pollution poses a significant global threat to ecosystems and human health, yet limited research exists in underdeveloped regions such as Bangladesh. This study investigates microplastic contamination in the Buriganga River, Dhaka, focusing on the impact of the nearby plastic recycling industry. Five different sites on the bank were selected to collect water and sediment samples. The microplastic particles from these samples were separated by density separation and filtration. The particles were photographed under a microscope to obtain length and surface area data by analyzing the microscope images. Shapes were obtained from the microscope images dividing all the particles into three types of shapes: fragment, filament, and fiber, with fragments being the most plentiful. Raman spectroscopy was used to identify the microplastic particles, and polystyrene was found to be abundant. Quantification of these particles showed the intense effect of the recycling industry, with particle counts thousands of times higher than those at the other sites. Most of the particles (53.6% in water and 68.7% in sediment) identified were 1–5 mm in size. The most abundant shape of particles was fragment in both water (67.9%) and sediment samples (85.8%), followed by fiber in water (19.6%) and filament in sediment (13.9%). Polypropylene (48%) and polystyrene (68%) were the most abundant types of plastics in water and sediment, respectively. Polyethylene was also identified in both water (24.5%) and sediment (10.2%). Downstream sites exhibit elevated microplastic levels, likely influenced by the recycling zone, while upstream sites, despite having less external activity, still show substantial microplastic contamination, indicating a complex interplay of factors contributing to river pollution. This study highlights the urgent need for improved waste management and targeted regulatory interventions on unregulated plastic recycling industries to mitigate microplastic pollution in urban rivers.

As the global energy crisis intensifies, there is an urgent need for sustainable alternatives to fossil fuels. Algae, with their high growth rates and ability to sequester carbon, present a promising solution for renewable energy and carbon capture. This study investigates the potential of various algal species for carbon capture through a comprehensive analysis of bubble column photobioreactors (BC-PBRs). By reviewing 102 relevant studies over the past 15 years, a total of 24 articles were identified, providing 650 data points on biomass yield in relation to design parameters such as aeration rate, column height, diameter, volume, and carbon dioxide concentration. The analysis revealed a positive correlation between biomass yield and column height (R = 0.48; range: 20–200 cm), total volume (R = 0.48; range: 1–70 L), and cultivation time (R = 0.47; range: 2–22 days). In contrast, a negative correlation was observed with carbon dioxide concentration (R = −0.12; range: 0.03–20%) and column diameter (R = −0.21; range: 2–24 cm). Notably, Chlorella spinulatus emerged as the most promising species among those studied, with the highest biomass yield (mean of 3.03 ± 1.12 g L⁻¹). This research highlights critical design considerations for optimizing BC-PBRs to enhance algal growth and biomass production.

Chromium is a heavy element that is extremely hazardous to both humans and the environment and is present in industrial waste. In this work, novel ZIF-8 MOFs doped with various molar ratios of cesium were prepared for the first time. Cs-2@ZIF-8 MOF was employed as an adsorbent material for removing Cr(VI) ions from wastewater. Several methods, like XRD, SEM/EDX, FT-IR, TEM, TGA, PL, BET, and XPS, were employed to characterize the physico-chemical and structural characteristics of the produced MOFs. The specific surface area of the ZIF-8 MOF was significantly enhanced from 1019.57 to 1204.95 m² g⁻¹ when doped with Cs ions. SEM images revealed that the Cs-2@ZIF-8 MOF particles had a flower-like morphology. TEM images of the Cs-2@ZIF-8 MOF revealed a rhombic dodecahedron structure, with crystallite diameters between 20 to 30 nm. TGA investigation revealed that the thermal stability of the ZIF-8 MOF increased significantly after doping with cesium. The impact of key experimental factors on the removal of Cr(VI) ions using Cs-2@ZIF-8 was studied in a batch mode. The Cs-2@ZIF-8 MOF had an adsorption capacity of 61.05 mg g⁻¹ for Cr(VI) adsorption, and even after four cycles, it maintained its removal ability. The Cr(VI) adsorption process employing the Cs-2@ZIF-8 MOF was exothermic and spontaneous, and it was in good agreement with the Freundlich isotherm and pseudo-second-order kinetics. The high recovery rate of Cr(VI) from actual water samples highlighted the excellent efficiency of the Cs-2@ZIF-8 MOF in wastewater remediation.