Environmental science. Advances最新文献

This study presents an investigation of a novel fouling-resistant mixed matrix membrane (MMM) composed of ultrafiltration PVC incorporating silica nanoparticles modified with sodium dodecyl sulfate (SiO₂-SDS) for carwash wastewater treatment. The hydrophilic SiO₂-SDS was synthesized by modifying SDS molecules onto the surfaces of silica nanoparticles (SiO₂ NPs). Later, SiO₂-SDS NPs were incorporated into a PVC polymeric matrix at an optimized ratio. The prepared virgin membrane and MMMs were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy-energy dispersive X-ray (SEM-EDX) spectroscopy, and atomic force microscopy (AFM). The results revealed that MMMs prepared with 0.15 wt% SiO₂-SDS NPs exhibited optimum characteristics and performance, where the highest thickness of 118.71 ± 0.42 μm and maximum porosity of 81.40 ± 0.23% were obtained. The pure water flux of this membrane reached 127.75 ± 1.72 L m⁻² h⁻¹, which is better than that of other modified membranes. This membrane achieved high removal of total suspended solids and chemical oxygen demand of 93% and 78%, respectively, when used with real carwash wastewater. Additionally, the 0.15 wt% SiO₂-SDS NPs exhibited stable performance during prolonged operation, resulting in the best flux recovery ratio of 80% among other tested membranes, signifying its superior fouling resistance bestowed by the hydrophilic nature of the incorporated SiO₂-SDS NPs.

Microplastic pollution constitutes a pressing global environmental issue impacting nearly every facet of human activity. This specific environmental challenge exerts profound yet still poorly understood influences on health, social dynamics, and industrial practices. A major obstacle for further investigation and mitigation of microplastics lies in their heterogeneity in size and composition. Additionally, the multitude of sources contributing to microplastic emissions further complicates their study. To enhance current detection and analytical methodologies for microplastics, this study exploits a novel approach for the easy and specific identification of microplastics within diverse environmental samples (including air, soil, lake water, rain, snow, and marine sediment) collected from various geographical locations across Canada. This method relies on fluorescent conjugated polymer nanoparticles that can be used to identify microplastics after minimal preparation. In all examined samples, originating from diverse sources and environments, microplastics were consistently present in the form of fragments and/or fibers, with polyethylene terephthalate (PET) emerging as the most abundant type, as confirmed via Raman spectroscopy either before or after labeling. This approach significantly streamlines the microplastic identification process, reducing the time needed for extraction and isolation. Our findings corroborate the efficacy of nanoparticle labeling for microplastic detection, offering promising avenues for their facile, specific, and reliable identification. Ultimately, this novel procedure holds potential to enhance remediation efforts targeting microplastics in the environment, thereby advancing our understanding of their global impact.

Microplastics (MPs), discharged from wastewater treatment plants (WWTPs), are found abundantly in freshwater systems. Along with MPs, various microorganisms that evade WWTP disinfection may colonize these particles, leading to biofouling. This study assessed the performance of six bacterial strains isolated from wastewater and the factors influencing biofilm formation using synthetic freshwater and polyethylene (PE) microplastics as a model. The effect of two PE microplastic sizes (180–200 μm and 3–4 mm) and three flow velocities (0.238, 0.11, and 0.077 m s⁻¹) were tested on the isolated strains' microbial growth and biofilm formation. Smaller MPs notably enhanced the growth rate. The treatment with small PE microplastics and a low flow velocity promoted the biofilm formation compared to a higher flow velocity where rapid microbial growth was observed but showed a lower biofilm formation after seven days of cultivation. These findings reveal how MP size and flow velocities influence biofilm development, advancing the understanding of MP-microbial interactions in freshwater aquatic environments.

The use of treated effluent/wastewater (TWW) for crop irrigation is gaining prominence globally due to growing freshwater scarcity. However, there are still questions about the safety of such a practice. This study sought to investigate and evaluate the health risks associated with the use of TWW for crop irrigation by assessing the potential risks arising from pathogens, heavy metals/potentially toxic elements (PTEs), micropollutants or pharmaceuticals and antibiotic resistance genes (ARGs), using tomato, carrot and cabbage as test crops. The levels of copper bioaccumulated in TWW irrigated crops were 25 mg kg⁻¹ for tomato, 30 mg kg⁻¹ for carrot and 20 mg kg⁻¹ for cabbage, while those of the control (tap water) were 30 mg kg⁻¹ for tomato, 40 mg kg⁻¹ for carrot and 65 mg kg⁻¹ for cabbage, respectively. Arsenic, cadmium and lead levels were below the detection limit for all treatments. The hazard quotient (HQ) and hazard index (HI) of copper and zinc were below 1 (adults) for TWW irrigated crops. Escherichia coli, Clostridium perfringens, coliform and thermotolerant bacteria were not detected on the fruits of tomato plants irrigated with TWW. All analysed pharmaceuticals were below the limit of detection except gabapentin, which was 3 μg kg⁻¹ in TWW irrigated tomatoes. tetA, ermB, bla_TEM, sul2, sul3 and qnrS genes were found in the metagenomic DNA extracted from TWW- and tap-irrigated cabbage. The results indicate no potential non-carcinogenic health risk for adult consumers and no microbial contamination of the tomato fruits under TWW irrigation. No difference was observed in the presence and distribution of the ARGs between TWW- and tap-irrigated crops, suggesting no contribution to the diffusion of different ARGs due to irrigation. Altogether, these findings highlight that health risk assessment of TWW for crop irrigation should focus on the quality of the TWW and on soil characteristics, which may contribute to risk exposure of different types of contaminants.

Harmful algal blooms (HABs) are a threat to aquatic ecosystems worldwide. New information is needed about the environmental conditions associated with the aerosolization and transport of HAB cells and their associated toxins. This information is critical to help inform our understanding of potential exposures. We used a ground-based sensor package to monitor weather, measure airborne particles, and collect air samples on the shore of a freshwater HAB (bloom of predominantly Rhaphidiopsis, Lake Anna, Virginia) and a marine HAB (bloom of Karenia brevis, Gulf Coast, Florida). Each sensor package contained a sonic anemometer, impinger, and optical particle counter. A drone was used to measure vertical profiles of windspeed and wind direction at the shore and above the freshwater HAB. At the Florida sites, airborne particle number concentrations (cm⁻³) increased throughout the day and the wind direction (offshore versus onshore) was strongly associated with these particle number concentrations (cm⁻³). Offshore wind sources had particle number concentrations (cm⁻³) 3 to 4 times higher than those of onshore wind sources. A predictive model, trained on a random set of weather and particle number concentrations (cm⁻³) collected over the same time period, was able to predict airborne particle number concentrations (cm⁻³) with an R squared value of 0.581 for the freshwater HAB in Virginia and an R squared value of 0.804 for the marine HAB in Florida. The drone-based vertical profiles of the wind velocity showed differences in wind speed and direction at different altitudes, highlighting the need for wind measurements at multiple heights to capture environmental conditions driving the atmospheric transport of aerosolized HAB toxins. A surface flux equation was used to determine the rate of aerosol production at the beach sites based on the measured particle number concentrations (cm⁻³) and weather conditions. Additional work is needed to better understand the short-term fate and transport of aerosolized cyanobacterial cells and toxins and how this is influenced by local weather conditions.

Access to clean water is under threat due to population growth, climate change, and pollution, emphasizing the need for effective wastewater treatment. Wastewater pollutants pose risks to public health and ecosystems, necessitating proper treatment methods. This paper outlines both conventional and emerging technologies for wastewater treatment. Established techniques, such as activated sludge processing, chlorination, and constructed wetlands, are discussed alongside newer methods, such as advanced oxidation, ultraviolet disinfection, membrane bioreactors, reverse osmosis, artificial intelligence optimization, and nanofiltration, which enhance contaminant removal but may incur high costs and energy demands. Integration of renewable energy sources, such as solar, wind, and biomass, into treatment facilities improves efficiency and reduces emissions. The process efficiency can be possibly enhanced through real-time monitoring and automation, while a sustainable and resource-efficient method involves integrating bio-electrochemical systems with constructed wetlands. There are still challenges in sludge handling, land requirements, and long-term system maintenance. Balancing technological solutions, environmental protection, and economic feasibility is essential for sustainable wastewater management, which can ensure continuous access to clean water in the face of increasing demand for this vital resource.

In January 2022, gaseous elemental Hg (GEM) concentrations were continuously monitored at Syowa Station on East Ongul Island, located ∼4 km from the continent on the eastern coast of Lützow-Holm Bay, to examine atmospheric Hg concentrations during the summer in the southeastern Antarctic region. Atmospheric GEM ranged from 0.36 to 1.83 ng m⁻³ average value: 1.01 ± 0.21 ng m⁻³ and increased during the day and decreased at night. While maintaining these diurnal variations, GEM concentrations increased to 1.99 and 1.55 ng m⁻³ on January 2–3 and 17–20, 2022, respectively. During both events, the low-pressure system approached the Syowa Station, and the 72 hours backward trajectory analysis revealed that the air mass originated from open water surfaces, implying that Hg evasion from the sea surface increased the atmospheric GEM concentration. To investigate the causes of diurnal variation causes—excluding these two events mentioned—Hg concentrations in the soil [n = 102, 2.61 ± 3.16 (0.14–19.0) ng g⁻¹], snow, glacier, and ice sheet around Syowa Station (n = 19, 0.45–5.60 ng L⁻¹), as well as in the atmosphere on the fast ice around the station (0.54–1.10 ng m⁻³), were measured. The results revealed that sources such as ornithogenic soil from the penguin rookery around the station, open water surfaces, and the gaseous oxidized Hg transported inland by katabatic winds did not contribute to the daytime GEM concentration increases. The cause of the summer diurnal variation at Syowa Station was unidentified and warrants further investigation.

Microplastic pollution is a growing environmental problem. Consequently, an emerging area of research is the analysis of these micro-particles, to identify the distribution and impacts of plastic in the environment. This paper details the development and application of a pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) method for the quantification of microplastic pollution in terrestrial samples. Initial analysis of plastic standards using Py-GC-MS revealed diagnostic pyrolytic products, which were utilised alongside internal standards and linear regression to create calibrations for each studied synthetic plastic. A microplastic extraction protocol for soils and sediments was developed, namely an overnight density separation with wet peroxide digestion, and its efficacy confirmed through spiking and recovery experiments. Matrix effects were observed for PE, PS and PVC, highlighting the need to use multiple diagnostic compounds per plastic, where possible. Overall, these findings demonstrate that Py-GC-MS can be successfully applied for the determination of microplastic concentrations in terrestrial samples, with a view to establishing effective mitigation strategies.

The transition to a low-carbon and resource-efficient circular economy is a political pillar of the EU and a priority for space agencies. Indeed, the space industry is pursuing sustainable development practices to reduce the environmental impacts. Life Cycle Assessment (LCA) is internationally recognized as the most appropriate methodology to estimate the environmental impacts of products, processes, and services and to evaluate the effectiveness of sustainability strategies related to reducing these negative externalities. To support the European Space Agency (ESA) in the process of planning more sustainable eco-design solutions, the objective of this paper is the development of a cradle-to-grave screening LCA study to assess the environmental impacts concerning the ESA's ground-based satellite tracking system based in New Norcia (AU) along its entire life cycle, including the tracking antenna and the photovoltaic panels. This scenario has been compared with 2 other scenarios to verify whether the use of photovoltaic panels has a benefit in terms of environmental impact (scenario A) and to understand the consequences in changing the location of the station, from New Norcia to Cebreros (E) by considering the change in the national energy mix from the Australian to the Spanish (scenario B). This study is one of the first attempts to apply the LCA methodology to the space sector, and its results, conducted according to ISO 14040/44 2021 guidelines and by means of the ReCiPe calculation method (2016), will be exploited by the ESA to plan a more sustainable eco-design for the construction of future space tracking stations.

The global burden of chronic kidney disease (CKD) in terms of mortality and disability-adjusted life years has increased, and this trend is expected to worsen over the next few decades. The primary cause of CKD is known to be due to hypertension and diabetes, however, over the last three decades, a form of CKD has been described in people without any known risk factors. These cases can be described as chronic kidney disease of an unknown etiology (CKDu). Cases of CKDu are rising primarily among rural agricultural communities in affected regions and occur mostly among young male farmers. There is no agreement on whether CKDu in these emerging clusters represents a single disease or a group of different diseases. As such, hypothesized causes of CKDu development include chronic occupational heat stress and dehydration, as well as exposure to environmental contaminants and agrochemicals, such as heavy metals and pesticides. The purpose of this critical review is to bring together the current literature on proposed CKDu etiologies, specifically those related to work in the agricultural sector. This review examines what is known about these occupational and environmental factors and their potential impact on the widespread epidemics of CKDu.