39 research outputs found

    Räumliche, zeitliche und quellenbedingte Variation Feinstaub induzierter Hydroxylradikalgenerierung

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    Die Fähigkeit von Partikeln Reaktive Sauerstoffspezies (ROS) zu bilden - als Metrik „ROS“ bezeichnet - gilt heutzutage als eine mögliche neue bzw. zusätzliche Beurteilungsmetrik hinsichtlich gesundheitsschädigender Effekte ausgelöst durch Partikel. Eine Erfassung dieser partikelbedingten Radikal¬bildung oder genauer des Wasserstoffperoxid abhängigen Hydroxylradikal(OH∙)-Bildungspotentials erfolgte in dieser Arbeit, unter Berücksichtigung der Aspekte Methodenentwicklung / -standardisierung und mögliche Gesundheitsrelevanz, mittels spin trap (5,5-dimethyl-1-pyrrolin-N-oxid, DMPO) basierter Elektronenspinresonanz Spektroskopie (ESR). Hierzu wurde eine von der etablierten Methodik abgewandelte Methodik erarbeitet und getestet, welche das ROS- Bildungspotential von PM Proben, gesammelt auf Quarzfaserfilter, erfasst. Des Weiteren wurde zwecks inter- und intralaboratorialen Vergleichs eine mögliche Standardisierung der spin trap basierten ESR-Methodik anhand von Metalllösungen und einem zertifiziertem Referenzmaterial untersucht. Basierend auf der abgewandelten Methodik (Nutzung von Quarzfaserfilter) und der etablierten Methodik (Nutzung von Teflonfilter) wurde zudem das PM induzierte, intrinsische OH∙-Bildungspotential von Filterproben, aus verschiedenen früheren durchgeführten Studien untersucht. Das OH∙-Bildungspotential dieser Proben wurde dabei u. a. hinsichtlich möglicher Standortabhängigkeiten, Quellen, chemischer Inhaltsstoffe und Gesundheitsrelevanz hin ausgewertet. Es zeigte sich dabei grundlegend ein Unterschied in der PM10 und PM1 induzierten OH•-Bildungsintensität, zwischen urbanen und ländlichen Räumen, mit höheren Werten für den urbanen und niedrigeren Werten für den ländlichen Raum. Zu erwartende detaillierte Standortabhängigkeiten (z. B. Verkehr, Wohngebiet) sowie saisonale Unterschiede sind lediglich andeutungsweise festgestellt worden. Des Weiteren konnte gezeigt werden, daß eine Quellenidentifizierung der OH•-Bildungsintensität in Kombination über die Erfassung der Luftmassenherkunft und einer Positiven Matrix Faktorisierung (PMF) möglich ist. Nach Anwendung eines Rückwärts-Trajektorienmodells und PMF ergaben sich demnach die größten zu erwartenden Quelleiträge für eine erhöhte OH•-Bildungsintensität durch Industrieemissionen und die Nutzung fossiler Brennstoffe. Ebenso wurde für PM2.5 Proben gezeigt, dass eine Ermittlung personenspezifischer Exposition mittels Landflächennutzungsregressionsmodell und mit personengetragener Sammeltechnik für die Partikel induzierte, intrinsische OH•-Bildungsintensität möglich ist. Dabei erwies sich der Innenraum aufgrund der hohen Aufenthaltsdauer von Personen als eine gegenüber dem Außenbereich nicht zu vernachlässigende Quelle möglicher partikelinduzierter OH∙-Bildung. In Bezug auf induzierte Gesundheitseffekte wurde erstmals eine eventuelle Verknüpfung des partikelbedingten OH∙-Bildungspotentials und dem Auftreten von Diabetes Typ II untersucht. Hierbei zeigte sich ein möglicherweise bestehender Zusammenhang, welcher jedoch zunächst weitergehend zu untersuchen ist bevor tiefergehende Rückschlüsse gezogen werden sollten. Zusammengefasst verdeutlichen die Ergebnisse dieser Arbeit das mögliche Anwendungspotential einer ESR basierten OH∙-Erfassung und deren Einsatz hinsichtlich verschiedener Fragestellungen in der Forschung

    Multiparametric in vitro genotoxicity assessment of different variants of amorphous silica nanomaterials in rat alveolar epithelial cells

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    The hazard posed to human health by inhaled amorphous silica nanomaterials (aSiO2 NM) remains uncertain. Herein, we assessed the cyto- and genotoxicity of aSiO2 NM variants covering different sizes (7, 15, and 40 nm) and surface modifications (unmodified, phosphonate-, amino- and trimethylsilyl-modified) on rat alveolar epithelial (RLE-6TN) cells. Cytotoxicity was evaluated at 24 h after exposure to the aSiO2 NM variants by the lactate dehydrogenase (LDH) release and WST-1 reduction assays, while genotoxicity was assessed using different endpoints: DNA damage (single- and double-strand breaks [SSB and DSB]) by the comet assay for all aSiO2 NM variants; cell cycle progression and γ-H2AX levels (DSB) by flow cytometry for those variants that presented higher cytotoxic and DNA damaging potential. The variants with higher surface area demonstrated a higher cytotoxic potential (SiO2_7, SiO2_15_Unmod, SiO2_15_Amino, and SiO2_15_Phospho). SiO2_40 was the only variant that induced significant DNA damage on RLE-6TN cells. On the other hand, all tested variants (SiO2_7, SiO2_15_Unmod, SiO2_15_Amino, and SiO2_40) significantly increased total γ-H2AX levels. At high concentrations (28 µg/cm2), a decrease in G0/G1 subpopulation was accompanied by a significant increase in S and G2/M sub-populations after exposure to all tested materials except for SiO2_40 which did not affect cell cycle progression. Based on the obtained data, the tested variants can be ranked for its genotoxic DNA damage potential as follows: SiO2_7 = SiO2_40 = SiO2_15_Unmod > SiO2_15_Amino. Our study supports the usefulness of multiparametric approaches to improve the understanding on NM mechanisms of action and hazard prediction.This work was supported by the Portuguese Foundation for Science and Technology (FCT) through ERA-NET SIINN project NanoToxClass (SIINN/0001/2013). This work was also supported by the NanoBioBarriers project (POCI-01-0145-FEDER-031162), co-financed by the Operational Program for Competitiveness and Internationalization (POCI) through European Regional Development Funds (FEDER/FNR); and by the Spanish Ministry of Science and Innovation: MCIN/AEI/10.13039/501100011033 (Grant PID2020-114908GA-I00); and the Ministry of Education, Culture and Sport BEAGAL18/00142 to V. Valdiglesias. F. Brandão (SFRH/BD/101060/2014) and M.J. Bessa (SFRH/BD/12046/2016) are recipients of FCT PhD scholarships. The Doctoral Program in Biomedical Sciences of the ICBAS – University of Porto offered additional funds. S. Fraga thanks FCT for funding through program DL 57/2016 – Norma transitória (Ref. DL-57/INSA-06/2018). Thanks are also due to FCT/MCTES for the financial support to EPIUnit (UIDB/04750/2020) and ITR (LA/P/0064/2020).info:eu-repo/semantics/publishedVersio

    Fine and ultrafine particles from indoor sources – Effects on healthy humans in a controlled exposure study and on lung epithelial cells in vitro

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    In recent years increasing concern has been expressed about the potential adverse health effects of particles from indoor sources. The aims of the EPIA project were: (1) to characterize potentially relevant indoor sources of (ultra)fine particles with respect to their emission levels and composition and (2) to investigate their adverse health effects. We investigated the effects of emissions from candle burning (CB), toasting of bread (TB) and sausage frying (FS) in a randomized, cross-over sham-controlled exposure study in healthy adults as well as in vitro in A549 human lung epithelial cells. Participants were exposed for 2 h to each of these sources at two different exposure levels, and examined before, during and after the exposures at defined time-intervals. We found transient associations between exposures and several respiratory and cardiovascular effects as well as inflammatory changes (e.g. lung function, blood pressure, arterial stiffness, interleukin-8 in nasal lavage/blood). Specific effects were found to depend strongly on the emission source and the selected exposure metric (e.g. size-specific particle mass concentration, size-specific particle number concentration, lung deposited surface area concentration). Evaluation of PM2.5 samples in the A549 cells, revealed an increased interleukin-8 release and DNA strand breakage induction for toasting, whereas candle burning only resulted in DNA damage. The results from our project demonstrate that elevated concentrations from certain indoor emission sources may lead to changes in the lung and cardiovascular systems as well as possibly induce inflammation

    Управління загрозами фінансовій безпеці підприємства

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    Розроблено блок-схему алгоритму управління загрозами фінансовій безпеці підприємства; виділено основні етапи здійснення цього процесу: оцінювання, аналіз та управління. Визначено сутність, зміст, переваги та недоліки застосування методів оцінювання загроз фінансовій безпеці в системі фінансового менеджменту підприємства. Ключові слова: підприємство, фінансова безпека, загрози, оцінювання, аналіз, управління.Составлена блок-схема алгоритма управления угрозами финансовой безопасности предприятия. Выделены основные этапы осуществления данного процесса: оценивание, анализ и управление. Определены сущность, содержание, преимущества и недостатки методов оценивания угроз финансовой безопасности в системе финансового менеджмента предприятия. Ключевые слова: предприятие, финансовая безопасность, угрозы, оценивание, анализ, управление.Enterprise financial security threats management main terms essence and contents were defined on the basis of financial and economic literature analysis and generalization: enterprise financial security threats management is a multistage process, which includes evaluation, management and analysis of enterprise financial security threats management; evaluation of enterprise financial security threats is a process of identification of threats influence on enterprise financial security; analysis of enterprise financial security threats is a process of threats identification, which influence on enterprise financial security. It is established that the majority of modern domestic and foreign scientists consider two groups of enterprise financial security threats estimation: qualitative or subjective (expert, probabilistic (concerning loss, favorable possibilities), consequences analysis) and quantitative or objective (statistical, analytical, rating, expense expediency, analogues, decision tree, normative). Comparative analysis of qualitative and quantitative enterprise financial security threats estimation enables to detect that use either of them has its own advantages and disadvantages. Some methods require using the considerable mass data and at the same time leave out of the account the time factor; others are insufficiently developed for using in the domestic economic conditions. Therefore the choice of the method is made only owing to the purpose of the enterprise financial security threats estimation. It is proved that the methods of the enterprise financial security threats management could be divided into three groups: reduction, maintenance and transmission. Reduction of enterprise financial security threats level provides preventive management and logistical measures implementation as to unfavorable events in financial and economic activities prevention or negative consequences liquidation. As measures, implemented for enterprise financial security threats level maintaining, could be referred the following: getting loans on compensation for losses, which enterprise got as a result of unforeseen, unfavorable events in its financial and economic activities, resumption of output production (goods, works, services) with the help of finance and credit establishments activities, government grants etc. Keywords: enterprise, financial security, threats, evaluation, analysis, management

    Evaluation of modelled versus observed NMVOC compounds at EMEP sites in Europe

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    •Atmospheric volatile organic compounds (VOC) constitute a wide range of species, acting as precursors to ozone and aerosol formation. Atmospheric chemistry and transport models (CTMs) are crucial to understanding the emissions, distribution, and impacts of VOCs. Given the uncertainties in VOC emissions, lack of evaluation studies, and recent changes in emissions, this work adapts the European Monitoring and Evaluation Programme Meteorological Synthesizing Centre – West (EMEP MSC-W) CTM to evaluate emission inventories in Europe. Here we undertake the first intensive model-measurement comparison of VOCs in two decades. The modelled surface concentrations are evaluated both spatially and temporally, using measurements from the regular EMEP monitoring network in 2018 and 2019, and a 2022 campaign. To achieve this, we utilised the UK National Atmospheric Emission Inventory to derive explicit emission profiles for individual species and employed a `tracer' method to produce pure concentrations that are directly comparable to observations. Model simulations for 2018 compare the use of two European inventories, CAMS and CEIP, and of two chemical mechanisms, CRIv2R5Em and EmChem19rc; those for 2019 and 2022 use CAMS and CRIv2R5Em only. •The degree to which the modelled and measured VOCs agree varies depending on the specific species. The model successfully captures the overall spatial and temporal variations of major alkanes (e.g., ethane, n-butane) and unsaturated species (e.g., ethene, benzene), but less though for propane, i-butane, and ethyne. This discrepancy underscores potential issues in the boundary conditions for these latter species and in their primary emissions from in particular the solvent and road transport sectors. Specifically, potential missing propane emissions and issues with its boundary conditions are highlighted by large model underestimations and smaller propane to ethane ratios compared to the measurement. Meanwhile, both the model and measurement show strong linear correlations among butane isomers and among pentane isomers, indicating common sources for these pairs of isomers. However, modelled ratios of i- to n-butane and i- to n-pentane are approximately one-third of the measured ratios, which is largely driven by significant emissions of n-butane and n-pentane from the solvent sector. This suggests issues with the speciation profile of the solvent sector, or underrepresented contributions from transport and fuel evaporation sectors in current inventories, or both. Furthermore, the modelled ethene-to-ethyne and benzene-to-ethyne ratios differ significantly from measured ratios. The different model performance strongly points to shortcomings in the spatial and temporal patterns and magnitudes of ethyne emissions, especially during winter. For OVOCs, modelled and measured methanal and methylglyoxal display a good agreement, which demonstrates that the model captures the overall photo-oxidation processes reasonably well. However, the insufficiency of suitable measurements limits the evaluation of other OVOCs. Finally, the model exhibits very similar performance across simulations using different inventories, which suggests that the emission profiles are likely to exert a more significant impact on the agreement between modelled and measured data than the total emissions reported for each sector. Therefore, the future focus may need to shift towards refining these speciation profiles through for example new emission measurement campaigns to improve the model accuracy

    Evaluation of modelled versus observed non-methane volatile organic compounds at European Monitoring and Evaluation Programme sites in Europe

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    Atmospheric volatile organic compounds (VOCs) constitute a wide range of species, acting as precursors to ozone and aerosol formation. Atmospheric chemistry and transport models (CTMs) are crucial to understanding the emissions, distribution, and impacts of VOCs. Given the uncertainties in VOC emissions, lack of evaluation studies, and recent changes in emissions, this work adapts the European Monitoring and Evaluation Programme Meteorological Synthesizing Centre – West (EMEP MSC-W) CTM to evaluate emission inventories in Europe. Here we undertake the first intensive model–measurement comparison of VOCs in 2 decades. The modelled surface concentrations are evaluated both spatially and temporally, using measurements from the regular EMEP monitoring network in 2018 and 2019, as well as a 2022 campaign. To achieve this, we utilised the UK National Atmospheric Emissions Inventory to derive explicit emission profiles for individual species and employed a tracer method to produce pure concentrations that are directly comparable to observations. The degree to which the modelled and measured VOCs agree varies depending on the specific species. The model successfully captures the overall spatial and temporal variations of major alkanes (e.g. ethane, n-butane) and unsaturated species (e.g. ethene, benzene) but less so for propane, i-butane, and ethyne. This discrepancy underscores potential issues in the boundary conditions for the latter species and in their primary emissions from, in particular, the solvent and road transport sectors. Specifically, potential missing propane emissions and issues with its boundary conditions are highlighted by large model underestimations and smaller propane-to-ethane ratios compared to the measurement. Meanwhile, both the model and measurements show strong linear correlations among butane isomers and among pentane isomers, indicating common sources for these pairs of isomers. However, modelled ratios of i-butane to n-butane and i-pentane to n-pentane are approximately one-third of the measured ratios, which is largely driven by significant emissions of n-butane and n-pentane from the solvent sector. This suggests issues with the speciation profile of the solvent sector, underrepresented contributions from transport and fuel evaporation sectors in current inventories, or both. Furthermore, the modelled ethene-to-ethyne and benzene-to-ethyne ratios differ significantly from measured ratios. The different model performance strongly points to shortcomings in the spatial and temporal patterns and magnitudes of ethyne emissions, especially during winter. For OVOCs, the modelled and measured concentrations of methanal and methylglyoxal show a good agreement, despite a moderate underestimation by the model in summer. This discrepancy could be attributed to an underestimation of contributions from biogenic sources or possibly a model overestimation of their photolytic loss in summer. However, the insufficiency of suitable measurements limits the evaluation of other OVOCs. Finally, model simulations employing the CAMS inventory show slightly better agreements with measurements than those using the Centre on Emission Inventories and Projections (CEIP) inventory. This enhancement is likely due to the CAMS inventory's detailed segmentation of the road transport sector, including its associated sub-sector-specific emission profiles. Given this improvement, alongside the previously mentioned concerns about the model's biased estimations of various VOC ratios, future efforts should focus on a more detailed breakdown of dominant emission sectors (e.g. solvents) and the refinement of their speciation profiles to improve model accuracy

    Genotoxicity and Gene Expression in the Rat Lung Tissue following Instillation and Inhalation of Different Variants of Amorphous Silica Nanomaterials (aSiO2 NM)

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    This article belongs to the Special Issue Cytotoxicity and Genotoxicity of Nanomaterials.Several reports on amorphous silica nanomaterial (aSiO2 NM) toxicity have been questioning their safety. Herein, we investigated the in vivo pulmonary toxicity of four variants of aSiO2 NM: SiO2_15_Unmod, SiO2_15_Amino, SiO2_7 and SiO2_40. We focused on alterations in lung DNA and protein integrity, and gene expression following single intratracheal instillation in rats. Additionally, a short-term inhalation study (STIS) was carried out for SiO2_7, using TiO2_NM105 as a benchmark NM. In the instillation study, a significant but slight increase in oxidative DNA damage in rats exposed to the highest instilled dose (0.36 mg/rat) of SiO2_15_Amino was observed in the recovery (R) group. Exposure to SiO2_7 or SiO2_40 markedly increased oxidative DNA lesions in rat lung cells of the exposure (E) group at every tested dose. This damage seems to be repaired, since no changes compared to controls were observed in the R groups. In STIS, a significant increase in DNA strand breaks of the lung cells exposed to 0.5 mg/m3 of SiO2_7 or 50 mg/m3 of TiO2_NM105 was observed in both groups. The detected gene expression changes suggest that oxidative stress and/or inflammation pathways are likely implicated in the induction of (oxidative) DNA damage. Overall, all tested aSiO2 NM were not associated with marked in vivo toxicity following instillation or STIS. The genotoxicity findings for SiO2_7 from instillation and STIS are concordant; however, changes in STIS animals were more permanent/difficult to revert.This work was funded by the Portuguese Foundation for Science and Technology (FCT) through ERA-NET SIINN project NanoToxClass (SIINN/0001/2013). FB and MJB are recipients of FCT PhD scholarships (SFRH/BD/101060/2014 and SFRH/BD/12046/2016). Thanks are due to FCT/MCTES for the financial support through national funds to EPIUnit (UIDB/04750/2020). J. Laloy performed STIS at the University of Namur with funding provided by BfR (grant agreement number 1329-561). F. Debacq-Chainiaux is a research associate at FRS-FNRS (National Funds for Scientific Research, Belgium).info:eu-repo/semantics/publishedVersio
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