Chemosphere最新文献

Perfluorooctane sulfonate (PFOS), a widely distributed and persistent organic pollutant, is known to cause immune dysfunction. In a previous study, we reported that PFOS modestly increases mast cell activation. However, its effects on FcεRI (a high-affinity IgE receptor)-mediated mast cell activation, a pivotal process in inflammatory allergic reactions and innate immunity, have not been clearly demonstrated. In this study, we investigated the effects of PFOS on IgE/Ag (antigen)-stimulated mast cell activation and the underlying mechanisms using bone marrow-derived mast cells (BMMCs) and a passive cutaneous anaphylaxis (PCA) mouse model. Oral administration of PFOS attenuated IgE/Ag-stimulated PCA responses. In the BMMCs model, PFOS reduced IgE/Ag-stimulated degranulation, intracellular Ca²⁺ levels, eicosanoid synthesis, and mRNA expression of pro-inflammatory cytokines. Consistently, PFOS decreased the phosphorylation of Syk and Lck, central tyrosine kinases in IgE/Ag-stimulated mast cell activation, along with their downstream signaling molecules (PLCγ1, AKT, and MAPKs), through the activation of tyrosine phosphatase Src homology region 2 domain-containing phosphatase-1. Additionally, PFOS reduced the phosphorylation of FcεRI-associated tyrosine kinases Fyn and Lyn. Fluorine-19 nuclear magnetic resonance spectroscopy revealed reduced fluorine signals of PFOS upon interaction with the plasma membrane, suggesting that PFOS accumulates in plasma membranes and interferes with FcεRI signaling by acting upstream, close to the membrane. Moreover, PFOS attenuated lipopolysaccharide-stimulated mRNA expression of TNFα and IL-6. In conclusion, PFOS exposure disrupts FcεRI-mediated allergic responses and modulates innate immune responses.

Liquid CO₂ (L-CO₂) has emerged as a safe and sustainable alternative to conventional organic solvents in dry cleaning owing to its non-toxic, non-flammable, and environmentally friendly nature. However, the compounds that can be removed from the fabrics by L-CO₂ are unknown. In this study, we optimized the temperature, flow rate, and co-solvent for L-CO₂ dry cleaning and identified the compounds that can be removed by this method using gas chromatography-time-of-flight mass spectrometry. A 7:3 (v/v) isopropanol(IPA)/water mixture was the optimal co-solvent mixture. Our L-CO₂+IPA/H₂O dry cleaning method exhibited high efficacy in removing a diverse range of substances, such as cholesterols, fatty acids, N-compounds, sugars, and sugar derivatives. In particular, 100% of the cholesterols were removed from the stained fabric.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). < This article has been retracted at the request of the Editors-in-Chief. A journal-wide investigation by Elsevier's Research Integrity & Publishing Ethics team identified violations of the journal's policies on authorship and conflict of interest related to the submission and review of this paper. An authorship change was made during the revision of this paper; the author Kathirvel Brindhadevi was added to the revised paper without validation or authorisation and credited with preparing the original draft. Review of this submission was handled by Guest Editor Thamaraiselvi Kaliannan despite an extensive record of collaboration, including co-publication, with one of the paper co-authors (Arivalagan Pugazhendhi). Acceptance of the article was partly based upon the positive advice of reviewers who were closely linked to one of the authors (Pugazhendhi). This compromised the editorial process and breached the journal's policies. The authors disagree with this retraction and dispute the grounds for it.>.

Gravity-driven membrane (GDM) systems are increasingly recognized as sustainable and energy-efficient solutions for decentralized water treatment. However, membrane fouling, particularly by organic matter, remains a significant operational challenge, necessitating regular chemical cleaning to maintain performance. The present study was undertaken to investigate the cleaning efficiency of sodium dichloroisocyanurate (NaDCC) tablets, a novel solid-state alternative to conventional liquid cleaning agents such as sodium hypochlorite (NaOCl), sodium lauryl sulfate (SLS), acetic acid, and citric acid. NaDCC tablets, originally developed for drinking water disinfection, offer advantages in terms of transport, storage, and safety compared with conventional liquid formulations. A comparative evaluation of cleaning agents was conducted on hollow fiber membranes used in GDM systems, with the concentration and contact times optimized for each chemical. NaOCl demonstrated the highest permeability recovery, reaching 48.29% at 500 mg L^-1 after 12 h, followed closely by NaDCC, with a recovery of 46.55% under similar conditions. Conversely, SLS, acetic acid, and citric acid presented significantly lower recovery rates, with maximum flux restorations of 14.57%, 14.90%, and 16.73%, respectively. These results highlight the comparable performance of NaDCC and NaOCl in addressing organic fouling while offering practical advantages such as greater stability and reduced chemical handling risks. This study highlights the efficacy of NaDCC as a viable detergent for GDM systems, and also provides a comprehensive comparative analysis of the water permeability performances of commercial detergents such as NaOCl, which cause various ecotoxicities, and suggests the feasibility of NaDCC as a chemical detergent in practical membrane processes. Our findings contribute to the development of more sustainable and cost-effective membrane-cleaning protocols that enhance long-term operational efficiency and minimize environmental impacts.

The increasing use of lithium (Li) in modern technology and medicine has raised up concerns in the scientific community due to the potential impact of this metal on the aquatic environment. Although several effects have been reported in different organisms, there is still scarce information concerning the mechanisms and chronic effects of Li toxicity in marine life. Our main objective is to determine biological effects of sub-lethal concentrations in Mytilus galloprovincialis at different biological organization levels using the biomarker approach. Mussels were exposed to environmental Li concentrations: 0.1, 1 and 10 mg/L. Samples of gills, muscle and digestive gland were taken at days 1, 7 and 21 for the assessment of biochemical, histochemical and histological endpoints. Results showed that exposure to Li caused greater impacts in a dose and time-dependent manner at different biological organization levels. Changes in acetylcholinesterase (AChE) activity were detected at day 1 (induction) and day 21 (inhibition) in accordance with increasing Li levels, indicating possible neurotoxic effects, while catalase (CAT) inhibition, and subsequent induction, was detected at day 1 in proportion to Li concentrations. Lysosomal biomarkers demonstrated a decreasing lysosomal membrane stability with higher Li doses after 21 days of exposure, whereas 10 mg Li/L provoked lysosomal size reduction from day 1. Finally, the integration of these biological responses into an IBR index indicated a clear effect of exposure after 21 days in a dose-dependent way, leading to cellular and tissue damage as consequence. Moreover, a time-course response was observed with an enhanced oxidative stress at day 1, and a neurotoxic effect, lysosomal membrane destabilization and histopathological alterations after 7 and 21 days of exposure to medium and high Li concentrations. Consequently, these findings provide valuable insights into Li's effects on marine life, emphasizing the need for further long-term studies across different biological organization levels.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). .

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). .

The Air Quality Health Index (AQHI) has long been introduced as an environmental health risk communication tool. Based on an epidemiological approach, it considers the combined effects of many air pollutants. However, comprehensive AQHI development for Thailand remains. This study aimed to develop the national AQHI in Thailand and determine whether sex- and age-specific AQHIs should be developed. The AQHI was constructed by examining the mortality risk associated with short-term exposure to multiple air pollutants using a time-stratified case-crossover design with the conditional Poisson regression model. This analysis utilized data from 31 provinces in Thailand from 2017 to 2020. The mortality risk associated with five criteria air pollutants-particulate matter with either 10 μm (PM₁₀) or 2.5 μm (PM_2.5) in aerodynamic diameter, as well as nitrogen dioxide (NO₂), sulfur dioxide (SO₂), ground-level ozone (O₃), and carbon monoxide (CO)-was calculated to construct the national AQHI and scaled it to a range from 0 to 10. The AQHIs were developed separately for age and sex, and the mortality risk associated with this established AQHI was explored and compared with that associated with the Air Quality Index (AQI). We found that the total AQHI and sex- and age-specific AQHIs were highly correlated with a similar association with mortality. The effects of AQHI on mortality were slightly more potent than AQI's, but their model fit statistics were comparable. In conclusion, developing specific AQHIs is unnecessary because their distributions and effects are similar to total AQHIs. The AQHI seems to be the better tool for communicating health risks related to air pollution, as the mortality risk associated with AQHI was more pronounced than that associated with AQI.

The formation of U(VI) intrinsic colloids has a non-negligible impact on the dissemination of actinides in the environment. It is therefore essential to better identify their nature, formation conditions, and stability domains. These specific points are especially important since the behavior of these elements in environment is generally estimated by geochemical transport modeling. This modeling relies on the accurate prediction of their speciation in various situations based on thermodynamic databases that have to be continuously updated. In this work, we identified and characterized the U(VI) intrinsic colloids that grow in model solutions having simplified composition that consists of NaCl and NaCl with Na₂SiO₃ electrolytes at pH comprised between 7 and 10. Using a simple, reliable and systematic method based on geochemical simulations, elemental analyses by ICP-AES and in situ Small and Wide Angle X-ray Scattering characterizations, several characteristics of U(VI) colloids such as their sizes, volumes, concentration and formula were determined and used to calculate the distribution ratio of U(VI) between intrinsic colloids and solution. This distribution ratio is crucial to enhance predictive geochemical calculation, especially to predict the fraction of U(VI) present as colloids that may migrate into natural waters.