| 1. |
- Abad, Esteban, et al.
(författare)
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Air monitoring with passive samplers for dioxin-like persistent organic pollutants in developing countries (2017-2019)
- 2021
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Ingår i: Chemosphere. - : Pergamon Press. - 0045-6535 .- 1879-1298. ; 287:Pt 1
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Tidskriftsartikel (refereegranskat)abstract
- As part of the global monitoring plan on persistent organic pollutants (GMP) under the Stockholm Convention passive air samplers equipped with polyurethane foam disks (PUFs) were applied to monitor dioxin-like POPs. For sampling, toluene-pretreated PUFs were exposed for three months during two years. Chemical analysis was performed in one accredited expert laboratory using internationally accepted methods; for comparison, all results were normalized to one PUF and 3 month exposure. Total TEQs, using WHO2005-TEFs, were lowest in the Pacific Islands countries (PAC) and had similar mean values in Africa (16.8 pg TEQ/PUF), Asia (16.9 pg TEQ/PUF), and Latin American and Caribbean countries (GRULAC, 13.3 pg TEQ/PUF). Using median values, Asia (13.4 pg TEQ/PUF) and GRULAC (13.1 pg TEQ/PUF) had higher amounts than Africa (6.1 pg TEQ/PUF) and PAC (2.1 pg TEQ/PUF). The contribution of PCDD/PCDF to the total TEQ was 2-3-times higher than from the dl-PCB. Mono-ortho PCB did not play a role in any of the samples. The previous 40 samples during 2010/2011 and the present 195 samples from 2017/2018 did not show a statistical difference (p value = 0.3), only for GRULAC, a downward trend was identified. It is recommended combining 4 PUFs to ‘annual’ samples.
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| 2. |
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| 3. |
- Aggarwal, Rahul, 1994, et al.
(författare)
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Freshwater ecotoxicity characterization factors for PMT/vPvM substances
- 2024
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Ingår i: Chemosphere. - 0045-6535 .- 1879-1298. ; 360
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Tidskriftsartikel (refereegranskat)abstract
- This study addresses the gap in freshwater ecotoxicological characterization factors (CFs) for Persistent, Mobile, and Toxic (PMT) and Very Persistent and Very Mobile (vPvM) substances. These CFs are vital for integrating the ecotoxicity impacts of these chemicals into life cycle assessments. Our goals are twofold: first, to calculate experimental freshwater CFs for PMT/vPvM substances listed by the German Environment Agency (UBA); second, to compare these CFs with those from the USEtox database. The expanded UBA list includes 343 PMT/vPvM substances, each representing a unique chemical structure, and linked to 474 REACH-registered substances. This study successfully computed CFs for 244 substances, with 107 overlapping the USEtox database and 137 being new. However, ecotoxicity data limitations prevented CF determination for 97 substances. This research enhances our understanding of freshwater CFs for PMT/vPvM substances, covering 72% of UBA's 343 PMT/vPvM substances. Data scarcity remains a significant challenge, which invariably impedes CF calculations. Notably, the disparities observed between CF values in the USEtox database and those derived in this research largely stem from variations in ecotoxicity data. Consequently, this research underscores the dynamic nature of CFs for substances, emphasizing the need for regular updates to ensure their accuracy and relevance.
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| 4. |
- Aggarwal, Ruchi, et al.
(författare)
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Sunlight promoted removal of toxic hexavalent chromium by cellulose derived photoactive carbon dots
- 2022
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 287
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Tidskriftsartikel (refereegranskat)abstract
- A scalable synthetic procedure for fabricating photoactive carbon dots (CD) from microcrystalline cellulose (MCC) is presented. The MCC was transformed into a photoactive nanosized CD by a one-step acid-assisted thermal-carbonization (~90 °C for 30 min). The efficiency of the obtained CD was determined by photo-removal of toxic hexavalent chromium (Cr(VI)) ions from wastewater. CD obtained from cellulose completely removed 20 ppm of Cr(VI) wastewater within ∼120 min under sunlight illumination. No Cr(VI) removal was observed in dark conditions and with control cellulose material as reference samples. The Cr(VI) removal follows pseudo-first-order kinetics along with a half-life of ∼26 min. Furthermore, the Cr(VI) removal from wastewater was supported via cyclic voltammetry analysis. Using a low-cost, naturally available cellulose material and sulfuric acid, the world's most-used chemical, creates techno-economic prerequisites for a scalable process of photoactive carbon dots.
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| 5. |
- Ahrens, Lutz, et al.
(författare)
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Environmental distribution of per- and polyfluoroalkyl substances (PFAS) on Svalbard: Local sources and long-range transport to the Arctic
- 2023
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Ingår i: Chemosphere. - 0045-6535 .- 1879-1298. ; 345
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Tidskriftsartikel (refereegranskat)abstract
- The environmental distribution of per- and polyfluoroalkyl substances (PFAS) in water, snow, sediment and soil samples taken along the west coast of Spitsbergen in the Svalbard archipelago, Norwegian Arctic, was determined. The contribution of potential local primary sources (wastewater, firefighting training site at Svalbard airport, landfill) to PFAS concentrations and long-range transport (atmosphere, ocean currents) were then compared, based on measured PFAS levels and composition profiles. In remote coastal and inland areas of Spitsbergen, meltwater had the highest mean ΣPFAS concentration (6.5 ± 1.3 ng L−1), followed by surface snow (2.5 ± 1.7 ng L−1), freshwater (2.3 ± 1.1 ng L−1), seawater (1.05 ± 0.64 ng L−1), lake sediments (0.084 ± 0.038 ng g−1 dry weight (dw)) and marine sediments (−1 dw, median 0.015 ng g−1 dw). Perfluoroalkyl sulfonates (PFSA) and 6:2 fluorotelomer sulfonate (FTSA) were predominant in water and soil samples influenced by local sources, while perfluoroalkyl carboxylates (PFCA) were predominant in water and sediment from remote coastal and inland areas of Svalbard. The PFAS composition profiles observed in remote areas indicated that atmospheric transport and oxidation of volatile precursors is an important source of PFCA on Svalbard. Shorter-chain PFAS such as perfluorobutanoate (PFBA) were the predominant PFAS in freshwater, reflecting replacement of C8-chained PFAS with shorter-chained compounds. The comparatively high PFAS (especially PFBA) concentration in meltwater indicated that melting of snow and ice during the Arctic spring is an important diffuse local PFAS source. This source may become even more important with climate warming-induced melting of Arctic glaciers and ice sheets. Further studies of mobilisation and transport of PFAS in the Arctic region are needed to confirm this trend.
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| 6. |
- Ahrens, Lutz, et al.
(författare)
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The relevant role of ion mobility separation in LC-HRMS based screening strategies for contaminants of emerging concern in the aquatic environment
- 2021
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 280
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Tidskriftsartikel (refereegranskat)abstract
- Ion mobility separation (IMS) coupled to high resolution mass spectrometry (IMS-HRMS) is a promising technique for (non-)target/suspect analysis of micropollutants in complex matrices. IMS separates ionized compounds based on their charge, shape and size facilitating the removal of co-eluting isomeric/isobaric species. Additionally, IMS data can be translated into collision cross-section (CCS) values, which can be used to increase the identification reliability. However, IMS-HRMS for the screening of contaminants of emerging concern (CECs) have been scarcely explored. In this study, the role of IMS-HRMS for the identification of CECs in complex matrices is highlighted, with emphasis on when and with which purpose is of use. The utilization of IMS can result in much cleaner mass spectra, which considerably facilitates data interpretation and the obtaining of reliable identifications. Furthermore, the robustness of IMS measurements across matrices permits the use of CCS as an additional relevant parameter during the identification step even when reference standards are not available. Moreover, an effect on the number of true and false identifications could be demonstrated by including IMS restrictions within the identification workflow. Data shown in this work is of special interest for environmental researchers dealing with the detection of CECs with state-of-the-art IMS-HRMS instruments.
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| 7. |
- Al-Hazmi, Hussein E., et al.
(författare)
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Polysaccharide nanocomposites in wastewater treatment : A review
- 2024
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Ingår i: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 347
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Forskningsöversikt (refereegranskat)abstract
- In modern times, wastewater treatment is vital due to increased water contamination arising from pollutants such as nutrients, pathogens, heavy metals, and pharmaceutical residues. Polysaccharides (PSAs) are natural, renewable, and non-toxic biopolymers used in wastewater treatment in the field of gas separation, liquid filtration, adsorption processes, pervaporation, and proton exchange membranes. Since addition of nanoparticles to PSAs improves their sustainability and strength, nanocomposite PSAs has gained significant attention for wastewater treatment in the past decade. This review presents a comprehensive analysis of PSA-based nanocomposites used for efficient wastewater treatment, focusing on adsorption, photocatalysis, and membrane-based methods. It also discusses potential future applications, challenges, and opportunities in adsorption, filtration, and photocatalysis. Recently, PSAs have shown promise as adsorbents in biological-based systems, effectively removing heavy metals that could hinder microbial activity. Cellulose-mediated adsorbents have successfully removed various pollutants from wastewater, including heavy metals, dyes, oil, organic solvents, pesticides, and pharmaceutical residues. Thus, PSA nanocomposites would support biological processes in wastewater treatment plants. A major concern is the discharge of antibiotic wastes from pharmaceutical industries, posing significant environmental and health risks. PSA-mediated bio-adsorbents, like clay polymeric nanocomposite hydrogel beads, efficiently remove antibiotics from wastewater, ensuring water quality and ecosystem balance. The successful use of PSA-mediated bio-adsorbents in wastewater treatment depends on ongoing research to optimize their application and evaluate their potential environmental impacts. Implementing these eco-friendly adsorbents on a large scale holds great promise in significantly reducing water pollution, safeguarding ecosystems, and protecting human health.
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| 8. |
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| 9. |
- Araújo, Mário J, et al.
(författare)
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Proteomics reveals multiple effects of titanium dioxide and silver nanoparticles in the metabolism of turbot, Scophthalmus maximus
- 2022
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Ingår i: Chemosphere. - : Pergamon-Elsevier Science Ltd. - 0045-6535 .- 1879-1298. ; 308
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Tidskriftsartikel (refereegranskat)abstract
- Titanium dioxide (TiO2) and silver (Ag) NPs are among the most used engineered inorganic nanoparticles (NPs); however, their potential effects to marine demersal fish species, are not fully understood. Therefore, this study aimed to assess the proteomic alterations induced by sub-lethal concentrations citrate-coated 25 nm ("P25") TiO2 or polyvinylpyrrolidone (PVP) coated 15 nm Ag NPs to turbot, Scophthalmus maximus. Juvenile fish were exposed to the NPs through daily feeding for 14 days. The tested concentrations were 0, 0.75 or 1.5 mg of each NPs per kg of fish per day. The determination of NPs, Titanium and Ag levels (sp-ICP-MS/ICP-MS) and histological alterations (Transmission Electron Microscopy) supported proteomic analysis performed in the liver and kidney. Proteomic sample preparation procedure (SP3) was followed by LC-MS/MS. Label-free MS quantification methods were employed to assess differences in protein expression. Functional analysis was performed using STRING web-tool. KEGG Gene Ontology suggested terms were discussed and potential biomarkers of exposure were proposed. Overall, data shows that liver accumulated more elements than kidney, presented more histological alterations (lipid droplets counts and size) and proteomic alterations. The Differentially Expressed Proteins (DEPs) were higher in Ag NPs trial. The functional analysis revealed that both NPs caused enrichment of proteins related to generic processes (metabolic pathways). Ag NPs also affected protein synthesis and nucleic acid transcription, among other processes. Proteins related to thyroid hormone transport (Serpina7) and calcium ion binding (FAT2) were suggested as biomarkers of TiO2 NPs in liver. For Ag NPs, in kidney (and at a lower degree in liver) proteins related with metabolic activity, metabolism of exogenous substances and oxidative stress (e.g.: NADH dehydrogenase and Cytochrome P450) were suggested as potential biomarkers. Data suggests adverse effects in turbot after medium/long-term exposures and the need for additional studies to validate specific biological applications of these NPs.
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| 10. |
- Ardalani, Hamidreza, et al.
(författare)
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Dietary quercetin impacts the concentration of pesticides in honey bees
- 2021
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 262
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Tidskriftsartikel (refereegranskat)abstract
- Honey bees are important pollinators and are subject to numerous stressors, such as changing floral resources, parasites, and agrochemical exposure. Pesticide exposure has been linked to the decline in the global honey bee population. We have limited knowledge of the metabolic pathways and synergistic effects of xenobiotics in bees. Quercetin is one of the most abundant phytochemicals in plants and is therefore abundant in the honey bee diet. Quercetin can upregulate the detoxification system in honey bees; however, it is still unknown to what extent quercetin ingestion can reduce the content of absorbed pesticides. In this study, we investigated the effect of dietary quercetin on the contents of three pesticides in honey bees: imidacloprid (insecticide), tebuconazole (fungicide), and tau-fluvalinate (insecticide and acaricide). Bees were divided into two main groups and fed either quercetin-sucrose paste or only sucrose for 72 h. Thereafter, they were orally exposed to ∼10 ng/bee imidacloprid or contact-exposed to ∼0.9 μg/bee tau-fluvalinate or ∼5.2 μg/bee tebuconazole. After 1 h of oral exposure or 24 h of contact exposure, the bees were anaesthetised with CO2, sacrificed by freezing, and extracted with a validated QuEChERS method. Subsequently, the concentrations of the three pesticides and quercetin in the bees were determined with a triple quadrupole tandem mass spectrometer coupled to an HPLC system. No significant effect on the concentration of tebuconazole or tau-fluvalinate was observed in bees fed quercetin. Intake of quercetin led to a reduction in the concentration of imidacloprid in honey bees. Quercetin-rich plants may be exploited in future beekeeping.
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