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A Seven-Years Based Characterization of Aerosol Light Scattering Properties at Central European Rural Site: Variability and Source Apportionment
Suchánková, Lenka ; Mbengue, S. ; Zíková, Naděžda ; Ondráček, Jakub ; Holubová Šmejkalová, A. ; Prokeš, R. ; Holoubek, I. ; Ždímal, Vladimír
The aim of this study is to focus on the temporal variations of light-scattering properties of aerosols at a rural background site in Central Europe. The total light scattering (σsp) and backscattering (σbsp) coefficients and associated calculated optical properties such as the Ångström exponent (SAE), the backscattering ratio (b), and the asymmetry factor (g), are characterized considering different time scales (annual, seasonal, monthly, or diurnal) based on long-term measurement. The optical properties were compared with meteorological conditions (fog, cloudiness), the concentrations of gaseous pollutants such as NOx and SO2 were inspected as well as potential sources of atmospheric aerosols. In addition, radiative forcing, and the influence of other meteorological conditions (e.g., height of planetary boundary layer), chemical composition and particle size distribution at the National Atmospheric Observatory Košetice (NAOK) are being further investigated to better understand the direct effects of aerosols on the local climate.
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The Story of Teamwork and the Birth of the FFP* (Filter Backpack)
Fraenkl, M. ; Krbal, M. ; Houdek, J. ; Zmrhalová, Z. ; Prokeš, B. ; Hejda, P. ; Slang, S. ; Přikryl, J. ; Ondráček, Jakub ; Makeš, Otakar ; Kostyk, Juraj ; Nasadil, P. ; Malčík, P. ; Ždímal, Vladimír ; Vlček, M.
Soon after the outbreak of the coronavirus crisis in the Czech Republic and the first lockdown (2020), we enthusiastically decided to fight the coronavirus with scientific \nmeans. Originally materials engineers, we decided to develop an effective protective respiratory device, which was in short supply at the time. We soon found out, that every textile material (handkerchief 10%) has a certain ability to catch an aerosol particle carrying the corona virus, the slower the aerosol particle (d<300 nm) passes through the filter, the greater the chance it has of being caught, with the thickness of the filter, the amount of passed particles decreases exponentially and breathing resistance increases linearly. On this basis, we decided to experiment with a large-area filter placed on the user's back (it wouldn't fit anywhere else) and commercially available textile filter material.
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Chemical composition and sources of atmospheric aerosols at the Frýdlant background station
Lhotka, Radek ; Pokorná, Petra ; Vodička, Petr ; Zíková, Naděžda ; Ondráček, Jakub ; Arora, S. ; Poulain, L. ; Hermann, H. ; Schwarz, Jaroslav ; Ždímal, Vladimír
This study assesses the variability of organic aerosol (OA) sources monitored at the rural background site Frýdlant. Non-refractory PM1 was evaluated in two seasons of\n2021. The positive matrix factorization with the multi-linear engine was used to determine the sources of OA at Frýdlant site, with four factors resolved both in winter and\nsummer.
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Lidar Vertical Profile Analyzes at National Atmospheric Observatory Košetice during Volcano Eruption on La Palma Island.
Kostyk, Juraj ; Holubová Šmejkalová, A. ; Ištok, T. ; Ždímal, Vladimír
Volcanic eruptions are one of the most important sources of natural aerosol. Their negative impacts on air quality (the effects of volcanic exhaust) can be observed via long-range transport to locations far from the eruption. One of the most recent events of volcanic activity was a volcanic eruption on La Palma in the fall of 2021 (Cumbre Vieja Volcano, La Palma Island, Canary Islands, 28°36'54 ,N 17°52'07 ,W, 1,949 m a.s.l.). The impact of the volcanic eruption on air quality, which occurred 3600 km from the National Atmospheric Observatory Košetice, was studied using a combination of ground-based measurements and vertical profile analyzes. Since a new instrument (LIDAR) has extended the equipment of our station, vertical profile analyzes were performed.
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Males-females differences in the spectrum of chromosomal aberrations in the group of nanocomposites production workers
Rössnerová, Andrea ; Pelcová, D. ; Ždímal, Vladimír ; Elzeinova, Fatima ; Margaryan, Hasmik ; Chvojková, Irena ; Topinka, Jan ; Schwarz, Jaroslav ; Ondráček, Jakub ; Koštejn, Martin ; Komarc, M. ; Vlčková, Š. ; Fenclová, Z. ; Lischková, L. ; Dvořáčková, Š. ; Rössner ml., Pavel
An increase in the use of nanomaterials (NM) has been witnessed in many areas of human life. Therefore, assessment of genotoxicity of NM and nanoparticles (NP) is one of the main objectives of genetic toxicology. Despite this fact, human cytogenetic studies following the exposure to NP are still rare. Moreover, no relevant information on possible differences in sensitivity to NP related to gender is available.\n\nIn this study we periodically (in September 2016, 2017 and 2018; pre-shift and post-shift each year) analyzed a group of workers (both genders), working long time in nanocomposites research, and matched controls. Aerosol exposure monitoring of particulate matter including nano-sized fractions was carried out during working shift. Micronucleus assay using Human Pan Centromeric probes, was applied to distinguish, besides the frequency of total MN in binucleated cells (BNC), also other types of chromosomal damage (losses and breaks). Moreover, whole-chromosome painting (WCP) for autosome #1 and both gonosomes (X and Y) were applied in third sampling period (2018) with the aim to identify the particular structural and numerical chromosomal aberrations.\n\nObtained results showed: (i) differences in the risk of exposure to NP related to individual working processes (welding, smelting and machining); (ii) differences in chemical composition of nano-fraction; (iii) no effect of chronic exposure of NP (total MN) opposite to significant effect of acute exposure; (iv) gender-related DNA damage differences (females seem to be more sensitive to chromosomal losses). Additional data from WCP suggested increased frequency of numerical aberrations in gonosomes.
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Personal exposure measurement during dental nanocomposite grinding
Ždímal, Vladimír ; Ondráčková, Lucie ; Ondráček, Jakub ; Schwarz, Jaroslav ; Bradna, P. ; Roubíčková, A. ; Pelclová, D. ; Rössnerová, Andrea
The purpose of this study was to measure the personal exposure of each participant of the study and to compare the results with those of static monitoring. Personal nanoparticle sam-plers (PENS), which can simultaneously detect both nanoparticles (PM0.1) and respirable parti-cles (PMA), were used to determine personal exposure (Tsai et al., 2012). Area monitoring in-cluded measurement of mass concentrations using the Berner Low Pressure Impactor (BLPI 25/0.018 /2, Hauke GmbH, Gmunden, Austria) and the Low Volume Sampler (LV5, Sven Leckel Ingenieurbüro GmbH, Germany). The number concentrations and their size distributions were measured with the Scanning Mobility Particle Sizer (5MP5 3936, T5I Inc., USA) and the Aerody-namic Particle Sizer (APS 3321, TSI Inc., USA). Measurements with all of the above- mentioned instruments were performed in four shifts with six participants per shift. Each participant milled for 10 minutes and then remained in the room until the group finished the session, so the total exposure lasted about 70 minutes. Due to the high content of filler nanoparticles, the nanocom-posite Filtek Ultimate (body A2, 3M ESPE, USA) was selected for these measurements.
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Biomarkers of Oxidative Stress and Inflammation in Researches Exposed to Nanoparticles by Inhalation During the Handling of Nanocomposites.
Pelclová, D. ; Ždímal, Vladimír ; Schwarz, Jaroslav ; Komarc, M. ; Vlčková, Š. ; Fenclová, Z. ; Lischková, L. ; Dvořáčková, Š. ; Rössnerová, Andrea ; Rössner ml., Pavel
At present, little is known about the health effects in the workers processing nanocomposites. In our study, 20 researchers (41.8 +/- 11.4 y/o), handling nanocomposites for 17.8 +/- 10.0 years were examined pre-shift and post-shift, together with 21 controls (42.7 +/- 11.5 y/o). Biomarkers of oxidative stress derived from lipids, nucleic acids, proteins and markers of inflammation were analyzed in the exhaled breath condensate (EBC). Aerosol exposure was monitored during three nanoparticle generation operations: smelting, welding and nanocomposite machining. Mass concentrations during these operations ranged from 0.120 to 1.840 mg/m(3), and median particle number concentrations from 4.8x10(4) to 5.4x10(5) particles/cm(3). Nanoparticles accounted for 40 to 95 % of particles, with Fe and Mn prevailing. Significant elevations were already seen in most oxidative stress markers and in several inflammation markers in the pre-shift samples relative to the controls. Significant associations were found between working in nanocomposite synthesis and the majority of EBC biomarkers. Chronic bronchitis was more frequent in researchers. A minor, but significant post-shift decrease of lung function parameters was found. We conclude that workers in nanocomposite synthesis may be at risk of developing airway disorders with time. From all the markers analyzed in EBC, the following markers were most robust and could be recommended for preventive examinations: 8-hydroxy-2-deoxyguanosine (8-OHdG) and 5-hydroxymethyl uracil (5-OHMeU) from nucleic acids, o-tyrosine (o-Tyr) and 3-nitrotyrosine (3-NOTyr) from proteins, and malondialdehyde and aldehydes C6-C13 from lipids. Among the markers of inflammation, tumor necrosis factor (TNF) and leukotriene B4 appeared to be the most useful.
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Study of aerosol properties with high time resolution
Kubelová, Lucie ; Ždímal, Vladimír (advisor) ; Hovorka, Jan (referee) ; Vojtíšek, Michal (referee)
This thesis focuses on physical and chemical characteristics of atmospheric aerosol measured with high time resolution. Size distribution, chemical composition, and volatility of submicron particles were studied in relation to meteorological conditions and other factors. To reach higher variability in ambient conditions, we considered atmospheric aerosol during two seasons of the year (summer and winter) and at two different locations (suburban site Prague Suchdol and rural site Košetice). Measurement during two different seasons enabled us to better distinguish the influence of seasonal sources such as domestic heating in winter and increased biogenic emissions in summer. Also, seasonal differences in meteorological conditions mainly in case of temperature, humidity, and solar radiation were shown to play a role in aerosol characteristics. A comparison of aerosol properties at two different measurement sites, namely a rural and suburban, enabled us to better characterize the role of background aerosol and the influence of the city. Furthermore, a transformation of aerosol particles entering indoors from outdoors was also studied within this thesis. The influence of indoor/outdoor temperature and humidity gradient as well as presence of new particle formation events on the indoor/outdoor ratio was...
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What is a connection between atmospheric aerosols, meteorological parameters and gaseous pollutants?
Slezáčková Zíková, Naděžda ; Ždímal, Vladimír (advisor) ; Hovorka, Jan (referee) ; Sedlák, Pavel (referee)
Title: What is the connection between atmospheric aerosols, meteorological pa- rameters and gaseous pollutants? Author: RNDr. Naděžda Slezáčková Zíková Department: Department of Meteorology and Environment Protection Supervisor: Ing. Vladimír Ždímal, Dr. Laboratory of Aerosol Chemistry and Physics, Institute of Chemical Process Fun- damentals, Czech Academy of Sciences, v.v.i. Abstract: Five years of atmospheric aerosol (AA) measurements at rural back- ground station Košetice were compared with meteorological records and gaseous pollutants concentrations. The sampling and data analysis of AA data is de- scribed, and the statistical evaluation is done. The variability in the AA con- centrations is significant; the long-term measurements of AA, over the period at least several years, and the differentiation according to the season of the year are thus necessary. The clearly expressed annual cycle of AA concentrations is mainly influenced by two phenomena. From April to September, the total AA concentration cycle is driven mainly by the new particles formation events, from October to March, the concentrations are strongly influenced by particles coming from long-range transport and/or from the regional pollution. The relationship between AA and meteorological parameters, however, is not only season...
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