Publications by authors named "Kamil Křůmal"

15 Publications

  • Page 1 of 1

Influence of boiler output and type on gaseous and particulate emissions from the combustion of coal for residential heating.

Chemosphere 2021 Mar 29;278:130402. Epub 2021 Mar 29.

Energy Research Center, VSB - Technical University of Ostrava, 17. Listopadu 2172/15, 708 00, Ostrava-Poruba, Czech Republic.

The study describes gaseous and particulate emissions from the combustion of two types of coal (hard and brown) in three types of boilers (one modern-type and two old-type boilers) used for residential heating. The importance of the heat outputs (nominal and two reduced outputs) for the emission of pollutants was also studied. Three outputs (95-108%, 58-73% and 26-50%) covered the expected operation of these boilers in real households under different outdoor air temperatures in the winter. Gaseous components (NO, SO, CO, CO, OGC) and particulate organic compounds (n-alkanes, polycyclic aromatic hydrocarbons, hopanes) were determined in the emissions. In general, the emission factors (EFs) of the products of incomplete combustion were higher from the combustion of coal in old-type boilers than from that in the modern-type boilers. The EFs of particulate matter varied between 11.6 and 17.0 g kg (hard coal, the oldest-type boiler), and 0.290 and 0.544 g kg (brown coal, the modern-type boiler). The trends between the EFs of particulate organic compounds and the outputs of boilers were observed only with the automatic boiler (modern-type boiler). Similar trends for old-type boilers were not observed, probably due to the high instability of the combustion process as a result of the old construction of these boilers. Diagnostic ratios of the PAHs and the homohopane index, used for source apportionment of particulate matter in ambient air, were calculated. While the calculated homohopane indexes were similar to those reported in the literature, the calculated diagnostic ratios for PAHs related to coal combustion were different.
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http://dx.doi.org/10.1016/j.chemosphere.2021.130402DOI Listing
March 2021

A Clearance Period after Soluble Lead Nanoparticle Inhalation Did Not Ameliorate the Negative Effects on Target Tissues Due to Decreased Immune Response.

Int J Mol Sci 2020 Nov 19;21(22). Epub 2020 Nov 19.

Laboratory of Molecular Morphogenesis, Institute of Animal Physiology and Genetics, v.v.i., Czech Academy of Sciences, 602 00 Brno, Czech Republic.

The inhalation of metal (including lead) nanoparticles poses a real health issue to people and animals living in polluted and/or industrial areas. In this study, we exposed mice to lead(II) nitrate nanoparticles [Pb(NO) NPs], which represent a highly soluble form of lead, by inhalation. We aimed to uncover the effects of their exposure on individual target organs and to reveal potential variability in the lead clearance. We examined (i) lead biodistribution in target organs using laser ablation and inductively coupled plasma mass spectrometry (LA-ICP-MS) and atomic absorption spectrometry (AAS), (ii) lead effect on histopathological changes and immune cells response in secondary target organs and (iii) the clearance ability of target organs. In the lungs and liver, Pb(NO) NP inhalation induced serious structural changes and their damage was present even after a 5-week clearance period despite the lead having been almost completely eliminated from the tissues. The numbers of macrophages significantly decreased after 11-week Pb(NO) NP inhalation; conversely, abundance of alpha-smooth muscle actin (α-SMA)-positive cells, which are responsible for augmented collagen production, increased in both tissues. Moreover, the expression of nuclear factor κB () and selected cytokines, such as tumor necrosis factor alpha (), transforming growth factor beta 1 (), interleukin 6(), and , displayed a tissue-specific response to lead exposure. In summary, diminished inflammatory response in tissues after Pb(NO) NPs inhalation was associated with prolonged negative effect of lead on tissues, as demonstrated by sustained pathological changes in target organs, even after long clearance period.
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http://dx.doi.org/10.3390/ijms21228738DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7699374PMC
November 2020

Gene Expression and Epigenetic Changes in Mice Following Inhalation of Copper(II) Oxide Nanoparticles.

Nanomaterials (Basel) 2020 Mar 18;10(3). Epub 2020 Mar 18.

Department of Genetic Toxicology and Epigenetics, Institute of Experimental Medicine of the Czech Academy of Sciences, 14220 Prague, Czech Republic.

We investigated the transcriptomic response and epigenetic changes in the lungs of mice exposed to inhalation of copper(II) oxide nanoparticles (CuO NPs) (8 × 10 NPs/m) for periods of 3 days, 2 weeks, 6 weeks, and 3 months. A whole genome transcriptome and miRNA analysis was performed using next generation sequencing. Global DNA methylation was assessed by ELISA. The inhalation resulted in the deregulation of mRNA transcripts: we detected 170, 590, 534, and 1551 differentially expressed transcripts after 3 days, 2 weeks, 6 weeks, and 3 months of inhalation, respectively. Biological processes and pathways affected by inhalation, differed between 3 days exposure (collagen formation) and longer treatments (immune response). Periods of two weeks exposure further induced apoptotic processes, 6 weeks of inhalation affected the cell cycle, and 3 months of treatment impacted the processes related to cell adhesion. The expression of miRNA was not affected by 3 days of inhalation. Prolonged exposure periods modified miRNA levels, although the numbers were relatively low (17, 18, and 38 miRNAs, for periods of 2 weeks, 6 weeks, and 3 months, respectively). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis based on miRNA-mRNA interactions, revealed the deregulation of processes implicated in the immune response and carcinogenesis. Global DNA methylation was not significantly affected in any of the exposure periods. In summary, the inhalation of CuO NPs impacted on both mRNA and miRNA expression. A significant transcriptomic response was already observed after 3 days of exposure. The affected biological processes and pathways indicated the negative impacts on the immune system and potential role in carcinogenesis.
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http://dx.doi.org/10.3390/nano10030550DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7153614PMC
March 2020

Variability in the Clearance of Lead Oxide Nanoparticles Is Associated with Alteration of Specific Membrane Transporters.

ACS Nano 2020 03 4;14(3):3096-3120. Epub 2020 Mar 4.

Laboratory of Molecular Morphogenesis, Institute of Animal Physiology and Genetics, v.v.i., Czech Academy of Sciences, Brno 602 00, Czech Republic.

Lead oxide nanoparticles (PbONPs), upon their entry into the lungs inhalation, induce structural changes in primary and secondary target organs. The fate and ultrastructural localization of PbONPs in organs is known to be dependent on the specific organ. Here, we focused on the differences in the ability to clear the inhaled PbONPs from secondary target organs and on molecular and cellular mechanisms contributing to nanoparticle removal. Mice were exposed to PbONPs in whole-body inhalation chambers. Clearance of ionic lead and PbONPs (Pb/PbONPs) from the lungs and liver was very effective, with the lead being almost completely eliminated from the lungs and the physiological state of the lung tissue conspicuously restored. Kidneys exposed to nanoparticles did not exhibit serious signs of damage; however, LA-ICP-MS uncovered a certain amount of lead located preferentially in the kidney cortex even after a clearance period. The concentration of lead in femurs, as representatives of the axial skeleton, was the highest among studied organs at all designated time points after PbONP exposure, and the clearance ability of lead from the femurs was very low in contrast to other organs. The organ-specific increase of ABC transporters expression (ABCG2 in lungs and ABCC3 in the liver) was observed in exposed animals, suggesting their involvement in removing Pb/PbONPs from tissues. Moreover, the expression of and displayed a tissue-specific response to lead exposure. Our results uncovered high variability among the organs in their ability to clear Pb/PbONPs and in the transporters involved in this process.
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http://dx.doi.org/10.1021/acsnano.9b08143DOI Listing
March 2020

The effects of nano-sized PbO on biomarkers of membrane disruption and DNA damage in a sub-chronic inhalation study on mice.

Nanotoxicology 2020 03 15;14(2):214-231. Epub 2019 Nov 15.

Faculty of Science, RECETOX, Masaryk University, Brno, Czech Republic.

Although the production of engineered nanoparticles increases our knowledge of toxicity and mechanisms of bioactivity during relevant exposures is lacking. In the present study mice were exposed to PbO nanoparticles (PbONP; 192.5 µg/m; 1.93 × 10 particles/cm) for 2, 5 and 13 weeks through continuous inhalation. The analyses addressed Pb and PbONP distribution in organs (lung, liver, kidney, brain) using electrothermal atomic absorption spectrometry and transmission electron microscopy, as well as histopathology and analyses of oxidative stress biomarkers. New LC-MS/MS methods were validated for biomarkers of lipid damage F2-isoprostanes (8-iso-prostaglandins F and E) and hydroxylated deoxoguanosine (8-OHdG, marker of DNA oxidation). Commonly studied malondialdehyde was also measured as TBARS by HPLC-DAD. The study revealed fast blood transport and distribution of Pb from the lung to the kidney and liver. A different Pb accumulation trend was observed in the brain, suggesting transfer of NP along the nasal nerve to the olfactory bulbs. Long-term inhalation of PbONP caused lipid peroxidation in animal brains (increased levels of TBARS and both isoprostanes). Membrane lipid damage was also detected in the kidney after shorter exposures, but not in the liver or lung. On the contrary, longer exposures to PbONP increased levels of 8-OHdG in the lung and temporarily increased lung weight after 2 and 5 weeks of exposure. The histopathological changes observed mainly in the lung and liver indicated inflammation and general toxicity responses. The present long-term inhalation study indicates risks of PbONP to both human health and the environment.
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http://dx.doi.org/10.1080/17435390.2019.1685696DOI Listing
March 2020

Six-week inhalation of CdO nanoparticles in mice: The effects on immune response, oxidative stress, antioxidative defense, fibrotic response, and bones.

Food Chem Toxicol 2020 Feb 9;136:110954. Epub 2019 Nov 9.

Institute of Analytical Chemistry of Czech Academy of Sciences, Veveri 97, 60200, Brno, Czech Republic.

Due to the growing number of applications of cadmium oxide nanoparticles (CdO NPs), there is a concern about their potential deleterious effects. The objective of our study was to investigate the effect of CdO NPs on the immune response, renal and intestine oxidative stress, blood antioxidant defence, renal fibrotic response, bone density and mineral content. Six-week-old female ICR mice were exposed to CdO NPs for 6 weeks by inhalation (particle size: 9.82 nm, mass concentration: 31.7 μg CdO/m, total deposited dose: 0.195 μg CdO/g body weight). CdO NPs increased percentage of thymus CD3eCD8a cells and moderately enhanced splenocyte proliferation and production of cytokines and chemokines. CdO NPs elevated pro-fibrotic factors (TGF-β2, α-SMA and collagen I) in the kidney, and concentrations of AGEs in the intestine. The ratio of GSH and GSSG in blood was slightly reduced. Exposure to CdO NPs resulted in 10-fold higher Cd concentration in tibia bones. No differences were found in bone mass density, mineral content, bone area values, bone concentrations of Ca, P, Mg and Ca/P ratio. Our findings indicate stimulation of immune/inflammatory response, oxidative stress in the intestine, starting fibrotic response in kidneys and accumulation of CdO NPs in bones of mice.
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http://dx.doi.org/10.1016/j.fct.2019.110954DOI Listing
February 2020

Content of metals in emissions from gasoline, diesel, and alternative mixed biofuels.

Environ Sci Pollut Res Int 2019 Oct 6;26(28):29012-29019. Epub 2019 Aug 6.

Institute of Analytical Chemistry of the Czech Academy of Sciences, Veveří 97, 602 00, Brno, Czech Republic.

The use of alternative fuels or biofuel blends could be a way to reduce the environmental burden of increasing traffic. The aim of this study was to compare emissions from conventional fuels and alternative biofuels for diesel and spark-ignition engines under comparable conditions, i.e., using the World Harmonized Transient Cycle for a heavy-duty diesel engine and the Artemis CADC driving cycle for automobiles powered by gasoline and alternative fuels. Total contents of Ba, Ce, Cd, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn were determined in emissions, fuels, and lubricating oils. In addition, the bioaccessibility of metals in emissions was also assessed by extraction in water and in simulated lung fluid (Gamble's solution). Total particulate mass emissions, expressed per kilogram of fuel, and total contents of metals were higher for the diesel engine than for spark-ignition engines. The highest metal contents in emissions from diesel and gasoline fuels were found for Fe, Zn, and Cu. Fe and Cu in emissions from diesel and spark-ignition engines declined with the addition of bio-components in fuels. However, there was no significant decrease in the contents of other metals in emissions from biofuels. The highest degrees of bioaccessibility were observed for Ba, Zn, Cd, and V in emissions from diesel and biodiesel (according to their solubility in water). On the basis of this study, the use of biodiesel (especially methylesters of rapeseed oil) can be recommended to reduce the total mass of particulate and metal emissions from diesel engines.
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http://dx.doi.org/10.1007/s11356-019-06144-4DOI Listing
October 2019

Comparison of emissions of gaseous and particulate pollutants from the combustion of biomass and coal in modern and old-type boilers used for residential heating in the Czech Republic, Central Europe.

Chemosphere 2019 Aug 29;229:51-59. Epub 2019 Apr 29.

Energy Research Center, VSB - Technical University of Ostrava, 17. Listopadu 15/2172, 708 33, Ostrava-Poruba, Czech Republic.

The chemical composition of emissions from old-type (an overfire boiler, a boiler with down-draft combustion) and modern-type (an automatic and a gasification boiler) boilers was compared. The boilers were operated with different fuels (brown and hard coal, wet and dry wood, wood pellets and brown coal briquettes) with reduced output (40-60%). The emissions were characterized by the contents of gaseous components (NO, SO, CO, CO, OGC); and particulate organic compounds (alkanes, polycyclic aromatic hydrocarbons, saccharides), including organic markers (monosaccharide anhydrides, diterpenoids, methoxyphenols, hopanes), which are used for source apportionment of particulate matter in ambient air. In general, emissions of the products of incomplete combustion (CO, particles, polycyclic aromatic hydrocarbons) were higher from the combustion of solid fuels in old-type boilers than from that in modern-type boilers. The modern-type (especially automatic) boilers were the most environmentally friendly. The highest concentrations of particulate matter (81.6-89.4 g kg) and particulate organic compounds (sum of PAHs: 225-275 mg kg) including organic markers were found in emissions from old-type (overfire) boilers, especially with the combustion of brown and hard coal. Characteristic ratios of selected organic compounds/markers applied for source identification were calculated. Computed characteristic ratios for monosaccharide anhydrides (biomass combustion) agreed with values in the literature. Homohopane indexes, frequently used for identification of coal combustion, and other characteristic ratios for PAHs, were different from the literature data. In our opinion, characteristic ratios for PAHs are not suitable for use in source apportionment.
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http://dx.doi.org/10.1016/j.chemosphere.2019.04.137DOI Listing
August 2019

Leukocyte telomere length is not affected by long-term occupational exposure to nano metal oxides.

Ind Health 2019 Nov 28;57(6):741-744. Epub 2019 Mar 28.

Institute of Chemical Process Fundamentals CAS, Czech Republic.

The aim of this study was to ascertain whether long-term occupational exposure to nanoparticles would affect relative leukocyte telomere length (LrTL). We analysed occupational exposure to size-resolved aerosol particles, with special emphasis on nanoparticles at two workshops: i/ the production of nanocomposites containing metal oxides; ii/ laboratory to test experimental exposure of nano-CuO to rodents. Thirty five exposed researchers (age 39.5 ± 12.6 yr; exposure duration 6.0 ± 3.7 yr) and 43 controls (40.4 ± 10.5 yr) were examined. LrTL did not significantly (p=0.14) differ between the exposed researchers (0.92 ± 0.13) and controls (0.86 ± 0.15). In addition, no significant correlation (r=-0.22, p=0.22) was detected between the duration of occupational exposure and LrTL. The results remained non-significant after multiple adjustments for age, sex and smoking status. Our pilot results suggest that relative leukocyte telomere length is not affected by occupational exposure to nanoparticles.
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http://dx.doi.org/10.2486/indhealth.2018-0146DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6885603PMC
November 2019

Inhalation of ZnO Nanoparticles: Splice Junction Expression and Alternative Splicing in Mice.

Toxicol Sci 2019 03;168(1):190-200

*Department of Genetic Toxicology and Nanotoxicology, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague 14220, Czech Republic.

Despite the wide application of nanomaterials, toxicity studies of nanoparticles (NP) are often limited to in vitro cell models, and the biological impact of NP exposure in mammals has not been thoroughly investigated. Zinc oxide (ZnO) NPs are commonly used in various consumer products. To evaluate the effects of the inhalation of ZnO NP in mice, we studied splice junction expression in the lungs as a proxy to gene expression changes analysis. Female ICR mice were treated with 6.46 × 104 and 1.93 × 106 NP/cm3 for 3 days and 3 months, respectively. An analysis of differential expression and alternative splicing events in 298 targets (splice junctions) of 68 genes involved in the processes relevant to the biological effects of ZnO NP was conducted using next-generation sequencing. Three days of exposure resulted in the upregulation of IL-6 and downregulation of BID, GSR, NF-kB2, PTGS2, SLC11A2, and TXNRD1 splice junction expression; 3 months of exposure increased the expression of splice junctions in ALDH3A1, APAF1, BID, CASP3, DHCR7, GCLC, GCLM, GSR, GSS, EHHADH, FAS, HMOX-1, IFNγ, NF-kB1, NQO-1, PTGS1, PTGS2, RAD51, RIPK2, SRXN1, TRAF6, and TXNRD1. Alternative splicing of TRAF6 and TXNRD1 was induced after 3 days of exposure to 1.93 × 106 NP/cm3. In summary, we observed changes of splice junction expression in genes involved in oxidative stress, apoptosis, immune response, inflammation, and DNA repair, as well as the induction of alternative splicing in genes associated with oxidative stress and inflammation. Our data indicate the potential negative biological effects of ZnO NP inhalation.
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http://dx.doi.org/10.1093/toxsci/kfy288DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6390655PMC
March 2019

The influence of local emissions and regional air pollution transport on a European air pollution hot spot.

Environ Sci Pollut Res Int 2019 Jan 17;26(2):1675-1692. Epub 2018 Nov 17.

Department of Aerosols Chemistry and Physics, Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, v.v.i, Rozvojová 1/135, 165 02, Prague 6 - Suchdol, Czech Republic.

The EU air quality standards have been frequently exceeded in one of the European air pollution hot spots: Ostrava. The aim of this study was to perform an air quality comparison between an urban site (Radvanice), which has a nearby metallurgical complex, and a suburban site (Plesná) to estimate air pollution sources and determine their local and/or regional origins. Twenty-four hour PM and PM (particular matter) concentrations, detailed mass size distributions (MSDs) to distinguish the sources of the fine and coarse PM, and their chemical compositions were investigated in parallel at both sites during the winter of 2014. Positive matrix factorization (PMF) was applied to the PM and PM chemical compositions to investigate their sources. During the measurement campaign, prevailing northeastern-southwestern (NE-SW) wind directions (WDs) were recorded. Higher average PM concentration was measured in Radvanice than in Plesná, whereas PM concentrations were similar at both sites. A source apportionment analysis revealed six and five sources for PM and PM, respectively. In Radvanice, the amount of PM and the most chemical species were similar under SW and NE WD conditions. The dominant sources were industrial (43% for PM and 27% for PM), which were caused by a large metallurgical complex located to the SW, and biomass burning (25% for PM and 36% for PM). In Plesná, the concentrations of PM and all species significantly increased under NE WD conditions. Secondary inorganic aerosols were dominant, with the highest contributions deriving from the NE WD. Therefore, regional pollution transport from the industrial sector in Silesian Province (Poland) was evident. Biomass burning contributed 22% and 24% to PM and PM, respectively. The air quality in Ostrava was influenced by local sources and regional pollution transport. The issue of poor air quality in this region is complex. Therefore, international cooperation from both states (the Czech Republic and Poland) is needed to achieve a reduction in air pollution levels.
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http://dx.doi.org/10.1007/s11356-018-3670-yDOI Listing
January 2019

Determination of short-term changes in levoglucosan and dehydroabietic acid in aerosols with Condensation Growth Unit - Aerosol Counterflow Two-Jets Unit - LC-MS.

Chemosphere 2018 Nov 4;210:279-286. Epub 2018 Jul 4.

Institute of Analytical Chemistry of the Czech Academy of Sciences, v. v. i., Veveří 97, 60200 Brno, Czech Republic.

Residential areas in urban agglomerations and also in the countryside are often burdened with high concentrations of aerosol in winter, this originating from local combustion sources. Aerosol sources can be identified by a monitoring of organic markers of biomass burning. Abundant markers of biomass and softwood burning are levoglucosan and dehydroabietic acid, respectively. The aim of this research was to develop an analytical method for the determination of levoglucosan and dehydroabietic acid in aerosol over short time periods involving aerosol sampling into liquid samples, quantitative pre-concentration of analytes, and their determination by liquid chromatography - mass spectrometry. A Condensation Growth Unit - Aerosol Counterflow Two-Jets Unit (CGU-ACTJU) sampler was used for the quantitative collection of aerosol directly into water. Dehydroabietic acid was pre-concentrated from the aqueous phase by solid phase extraction (C-18). Afterwards, levoglucosan in water samples was concentrated on a vacuum evaporator. The detection limits of levoglucosan and dehydroabietic acid were 28 ng m and 5.5 ng m, respectively. The results obtained by the developed method were compared with an independent determination of both markers in aerosol by means of the sampling of aerosols on a filter and subsequent analysis by GC-MS. The developed method demonstrated sufficient agreement with the independent determination for generated standard aerosol as well as for urban aerosol over an eight-day winter campaign. The presented method allows the monitoring of concentration changes in biomass burning markers in 2-h intervals.
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http://dx.doi.org/10.1016/j.chemosphere.2018.07.015DOI Listing
November 2018

Source apportionment of aerosol particles at a European air pollution hot spot using particle number size distributions and chemical composition.

Environ Pollut 2018 Mar 22;234:145-154. Epub 2017 Nov 22.

Center for Air Resources Engineering and Science, Clarkson University, Potsdam, NY 13699-5708, USA; Department of Public Health Sciences, University of Rochester Medical Center, Rochester, NY, USA.

Ostrava in the Moravian-Silesian region (Czech Republic) is a European air pollution hot spot for airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), and ultrafine particles (UFPs). Air pollution source apportionment is essential for implementation of successful abatement strategies. UFPs or nanoparticles of diameter <100 nm exhibit the highest deposition efficiency in human lungs. To permit apportionment of PM sources at the hot-spot including nanoparticles, Positive Matrix Factorization (PMF) was applied to highly time resolved particle number size distributions (NSD, 14 nm-10 μm) and PM chemical composition. Diurnal patterns, meteorological variables, gaseous pollutants, organic markers, and associations between the NSD factors and chemical composition factors were used to identify the pollution sources. The PMF on the NSD reveals two factors in the ultrafine size range: industrial UFPs (28%, number mode diameter - NMD 45 nm), industrial/fresh road traffic nanoparticles (26%, NMD 26 nm); three factors in the accumulation size range: urban background (24%, NMD 93 nm), coal burning (14%, volume mode diameter - VMD 0.5 μm), regional pollution (3%, VMD 0.8 μm) and one factor in the coarse size range: industrial coarse particles/road dust (2%, VMD 5 μm). The PMF analysis of PM revealed four factors: SIA/CC/BB (52%), road dust (18%), sinter/steel (16%), iron production (16%). The factors in the ultrafine size range resolved with NSD have a positive correlation with sinter/steel production and iron production factors resolved with chemical composition. Coal combustion factor resolved with NSD has moderate correlation with SIA/CC/BB factor. The organic markers homohopanes correlate with coal combustion and the levoglucosan correlates with urban background. The PMF applications to NSD and chemical composition datasets are complementary. PAHs in PM were found to be associated with coal combustion factor.
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http://dx.doi.org/10.1016/j.envpol.2017.10.097DOI Listing
March 2018

WITHDRAWN: Wet effluent diffusion denuder: The tool for determination of monoterpenes in forest.

Talanta 2016 09 17;158:192. Epub 2015 Dec 17.

Institute of Analytical Chemistry of the CAS, v. v. i., Veveří 97, 60200 Brno, Czech Republic.

The Publisher regrets that this article is an accidental duplication of an article that has already been published, 10.1016/j.talanta.2016.03.032. The duplicate article has therefore been withdrawn.The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
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http://dx.doi.org/10.1016/j.talanta.2015.12.041DOI Listing
September 2016

Wet effluent diffusion denuder: The tool for determination of monoterpenes in forest.

Talanta 2016 06 11;153:260-7. Epub 2016 Mar 11.

Institute of Analytical Chemistry of the CAS, v. v. i., Veveří 97, 60200 Brno, Czech Republic.

Three methods, i.e., the cylindrical wet effluent diffusion denuder (CWEDD)-GCMS, Tenax tubes-GCMS and Proton-Transfer-Reaction Time-of-Flight Mass Spectrometry (PTR-TOF-MS) were compared for the determination of monoterpenes in forest. While the on-line technique (PTR-TOF-MS) allows only for the measurement of sum of monoterpenes, both the off-line preconcentration techniques (CWEDD and Tenax tubes) are suitable for the determination of concentrations of individual monoterpenes due to subsequent analysis of samples by GCMS. The CWEDD-GCMS is the only method that allows sampling of individual monoterpenes with short time intervals of 2-5min. Monoterpenes are absorbed into a liquid (n-heptane), flowing down on the inner wall of the CWEDD, and then the collected liquid with monoterpenes is immediately taken away for the GCMS analysis, which minimizes time when collected monoterpenes are exposed to oxidants presented in the air during sampling. The limits of detection of CWEDD-GCMS are in the range 1-7pptv for individual monoterpenes.
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http://dx.doi.org/10.1016/j.talanta.2016.03.032DOI Listing
June 2016