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Organické sloučeniny a markery ze spalování dřeva v kotlích používaných pro vytápění domácností
Křůmal, Kamil ; Mikuška, Pavel ; Horák, J. ; Jaroch, M. ; Hopan, F. ; Kuboňová, L.
V emisích ze spalování tvrdého a měkkého dřeva byly měřeny organické sloučeniny (polycyklické aromatické uhlovodíky) a organické markery (monosacharidové anhydridy, diterpenoidy) používané pro identifikaci zdrojů emisí aerosolů. Dřevo bylo spalováno v různých kotlích používaných k vytápění bytů v České republice, tj. v protápěcím kotli, kotli s tahem spalování, zplyňovacím kotli a automatickém kotli. Emisní faktory částic a všech měřených organických sloučenin byly nejvyšší ze spalování paliv v nejstarším (přehořívacím) kotli.
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Parallel Determination of Particulate Ammonium by Using a Continuous Aerosol Sampler and Cascade Impactor
Alexa, Lukáš ; Hlaváčková, H. ; Cigánková, Hana ; Mikuška, Pavel
Ammonia is a significant gaseous pollutant present in the atmosphere. As a neutralizing agent of acidic species ammonia forms particle-phase ammonium (NH4+) salts and contributes thus to formation of secondary atmospheric aerosols (Harrison and Jones, 1995). Aerosols (particulate matter, PM) are responsible for many negative effects on environments and health risks to human. The diameter of PM has significant impact on their environmental exposure, where the decreasing particle size increases the adverse health effects. The ultrafine particles hence play a major role in adverse impact on human health (Ryer-Powder, 1991). Presented paper describes the use of the novel continuous aerosol sampler for online, and a commercial cascade impactor for offline, determination of NH4+ in ambient air.
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Oxidative Potential of PM1 and PM2.5 Urban Aerosol and Associated Elements in Three Simulated Lung Fluids
Cigánková, Hana ; Mikuška, Pavel ; Hegrová, J.
Mass concentration of particulate matter (PM) has been used in several epidemiologic studies as an indicatior conenecting PM concentrations with human health effects (Ostro, 1993). However, mass concentration of PM doesn´t consider the different compositions and toxicological effects of its components. Majority of PM mass constitutes low-toxicity components, while minority of trace components may have high toxicological activity (Tonne, 2012). Oxidative potential (OP), defined as the ability of PM to induce oxidative stress, is in recent years recognized as one of the main biological mechanisms considered to be contributing to negative impacts from air pollution exposure. Oxidative stress is caused through the capability of PM to generate reactive oxygen species (ROS) within the lung, which leads to pro-inflammatory responses that can ultimately results in cell apoptosis (Borlaza, 2021).
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Three Years of Experience with Measurement of Cloud Condensation Nuclei Concentrations Using Cloud Condensation Nuclei Counter CCN-200
Moravec, Pavel ; Lhotka, Radek ; Ždímal, Vladimír
Aerosol particles in the atmosphere that allow water vapor to condense and form cloud droplets are called Cloud Condensation Nuclei (CCN). Elevated concentrations of \nCCN tend to increase the concentration and decrease the size of droplets. This can lead to suppression of precipitation in shallow and short-lived clouds and to greater convective \noverturning and more precipitation in deep convective clouds. The response of cloud properties and precipitation processes to increasing anthropogenic aerosol concentrations represents one of the largest uncertainties in the current understanding of climate change. One of the fundamental challenges is to determine the ability of aerosol particles to act as CCN under relevant atmospheric conditions. Knowledge of the spatial and temporal distribution in the atmosphere is essential to incorporate the effects of CCN into meteorological models of all scales, Huang et al. (2007). Long-term CCN measurements are performed at aerosol monitoring sites such as those forming ACTRIS (Aerosols, Clouds and Trace Gases Research Infrastructure) network. In this paper, we present the three-year experience of measuring CCN concentrations over the National Atmospheric Observatory Košetice (NAOK), a rural background site in the Czech Republic. The first results of these measurements were presented by Mishra et al. (2022)
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The impact of covid-19 restrictions on carbonaceous aerosols at rural background site: importance of vertical distribution
Mbengue, Saliou ; Vodička, Petr ; Komínková, Kateřina ; Schwarz, Jaroslav ; Zíková, Naděžda ; Prokeš, Roman ; Suchánková, Lenka ; Julaha, Kajal ; Ondráček, Jakub ; Holoubek, Ivan ; Ždímal, Vladimír
In this study, EC and OC at 4 m elevation and EC at 230 m elevation showed a similar \nseasonal pattern with higher values in winter and lower values in summer. OC, measured \nat 230 m height showed an opposite behavior with slightly higher values in spring and \nsummer, probably related to the increased contribution of secondary organic carbon \n(SOC). Concentrations were generally higher at 4 m, where there was also a better \ncorrelation between EC and OC, suggesting a greater influence of local sources near the \nsurface.
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NMR Aerosolomics Study of Water-Soluble Organic Compounds in Size-Resolved Particulate Matter
Horník, Štěpán ; Vodička, Petr ; Pokorná, Petra ; Schwarz, Jaroslav ; Ždímal, Vladimír ; Sýkora, Jan
Organic aerosols (OA) account for a significant fraction (10 – 90%) of atmospheric particulate matter (Hallquist et al., 2009). The composition of organic aerosols is very complex and is usually characterized by their water solubility. Water-soluble organic compounds (WSOC) constitute a large fraction of OA (10 – 80%) and consist of chemical species containing oxygenated functional groups such as hydroxyl, carboxyl, or carbonyl groups. NMR spectroscopy represents an alternative to commonly used techniques (gas chromatography-mass spectrometry, liquid chromatography-based techniques) for WSOC analysis. Our recently introduced method, called NMR aerosolomics, allows quantitative analysis of dozens of individual compounds from different aerosol samples. An important part of the characterization of aerosols is their classification by particle size. The analysis of individual compounds in the size-resolved fractions of the WSOC class has been performed only in a few studies that focus mainly on a particular subclass of compounds or use multiple analytical techniques.
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10leté monitorování oxidačního stresu u osob profesionálně exponovaných nanočásticím pomocí neinvazivních metod
Pelclová, D. ; Ždímal, Vladimír
Markery oxidačního stresu mohou být dostupnou metodou k monitorování efektu při inhalaci nanočásticím v pracovním prostředí, lze přitom využít neinvazivního odběru tekutin. Vzhledem k experimentálním studiím i výsledkům studií u pacientů s inhalačníexpozicí karcinogennímu SiO2 a azbestu je potřebné monitorovat expozici kromě měření \naerosolů v ovzduší také tímto expozičním testem z biologického materiálu. Minimální velikost skupiny je 20 pracovníků a 20 kontrolních osob ze stejné lokality. Doporučujeme \nvyšetřit alespoň jeden marker oxidace lipidů, nukleových kyselin a proteinů. Vhodné načasování je po směně na konci týdne, kdy markery oxidačního stresu ve všech třech \nbiologických tekutinách odrážejí jak akutní, tak chronický efekt expozice.
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