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1.
Nanomaterials (Basel) ; 13(4)2023 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-36839135

RESUMO

Titanium dioxide nanoparticles (TiO2 NPs) are used in a wide range of applications. Although inhalation of NPs is one of the most important toxicologically relevant routes, experimental studies on potential harmful effects of TiO2 NPs using a whole-body inhalation chamber model are rare. In this study, the profile of lymphocyte markers, functional immunoassays, and antioxidant defense markers were analyzed to evaluate the potential adverse effects of seven-week inhalation exposure to two different concentrations of TiO2 NPs (0.00167 and 0.1308 mg TiO2/m3) in mice. A dose-dependent effect of TiO2 NPs on innate immunity was evident in the form of stimulated phagocytic activity of monocytes in low-dose mice and suppressed secretory function of monocytes (IL-18) in high-dose animals. The effect of TiO2 NPs on adaptive immunity, manifested in the spleen by a decrease in the percentage of T-cells, a reduction in T-helper cells, and a dose-dependent decrease in lymphocyte cytokine production, may indicate immunosuppression in exposed mice. The dose-dependent increase in GSH concentration and GSH/GSSG ratio in whole blood demonstrated stimulated antioxidant defense against oxidative stress induced by TiO2 NP exposure.

2.
Part Fibre Toxicol ; 19(1): 52, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35922858

RESUMO

BACKGROUND: Inhalation of lead oxide nanoparticles (PbO NPs), which are emitted to the environment by high-temperature technological processes, heavily impairs target organs. These nanoparticles pass through the lung barrier and are distributed via the blood into secondary target organs, where they cause numerous pathological alterations. Here, we studied in detail, macrophages as specialized cells involved in the innate and adaptive immune response in selected target organs to unravel their potential involvement in reaction to subchronic PbO NP inhalation. In this context, we also tackled possible alterations in lipid uptake in the lungs and liver, which is usually associated with foam macrophage formation. RESULTS: The histopathological analysis of PbO NP exposed lung revealed serious chronic inflammation of lung tissues. The number of total and foam macrophages was significantly increased in lung, and they contained numerous cholesterol crystals. PbO NP inhalation induced changes in expression of phospholipases C (PLC) as enzymes linked to macrophage-mediated inflammation in lungs. In the liver, the subchronic inhalation of PbO NPs caused predominantly hyperemia, microsteatosis or remodeling of the liver parenchyma, and the number of liver macrophages also significantly was increased. The gene and protein expression of a cholesterol transporter CD36, which is associated with lipid metabolism, was altered in the liver. The amount of selected cholesteryl esters (CE 16:0, CE 18:1, CE 20:4, CE 22:6) in liver tissue was decreased after subchronic PbO NP inhalation, while total and free cholesterol in liver tissue was slightly increased. Gene and protein expression of phospholipase PLCß1 and receptor CD36 in human hepatocytes were affected also in in vitro experiments after acute PbO NP exposure. No microscopic or serious functional kidney alterations were detected after subchronic PbO NP exposure and CD68 positive cells were present in the physiological mode in its interstitial tissues. CONCLUSION: Our study revealed the association of increased cholesterol and lipid storage in targeted tissues with the alteration of scavenger receptors and phospholipases C after subchronic inhalation of PbO NPs and yet uncovered processes, which can contribute to steatosis in liver after metal nanoparticles exposure.


Assuntos
Nanopartículas Metálicas , Fosfolipases Tipo C , Colesterol , Humanos , Inflamação , Chumbo , Macrófagos , Nanopartículas Metálicas/química , Óxidos
3.
Front Immunol ; 13: 874253, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547729

RESUMO

Copper oxide nanoparticles (CuO NPs) are increasingly used in various industry sectors. Moreover, medical application of CuO NPs as antimicrobials also contributes to human exposure. Their toxicity, including toxicity to the immune system and blood, raises concerns, while information on their immunotoxicity is still very limited. The aim of our work was to evaluate the effects of CuO NPs (number concentration 1.40×106 particles/cm3, geometric mean diameter 20.4 nm) on immune/inflammatory response and antioxidant defense in mice exposed to 32.5 µg CuO/m3 continuously for 6 weeks. After six weeks of CuO NP inhalation, the content of copper in lungs and liver was significantly increased, while in kidneys, spleen, brain, and blood it was similar in exposed and control mice. Inhalation of CuO NPs caused a significant increase in proliferative response of T-lymphocytes after mitogenic stimulation and basal proliferative activity of splenocytes. CuO NPs significantly induced the production of IL-12p70, Th1-cytokine IFN-γ and Th2-cytokines IL-4, IL-5. Levels of TNF-α and IL-6 remained unchanged. Immune assays showed significantly suppressed phagocytic activity of granulocytes and slightly decreased respiratory burst. No significant differences in phagocytosis of monocytes were recorded. The percentage of CD3+, CD3+CD4+, CD3+CD8+, and CD3-CD19+ cell subsets in spleen, thymus, and lymph nodes did not differ between exposed and control animals. No changes in hematological parameters were found between the CuO NP exposed and control groups. The overall antioxidant protection status of the organism was expressed by evaluation of GSH and GSSG concentrations in blood samples. The experimental group exposed to CuO NPs showed a significant decrease in GSH concentration in comparison to the control group. In summary, our results indicate that sub-chronic inhalation of CuO NPs can cause undesired modulation of the immune response. Stimulation of adaptive immunity was indicated by activation of proliferation and secretion functions of lymphocytes. CuO NPs elicited pro-activation state of Th1 and Th2 lymphocytes in exposed mice. Innate immunity was affected by impaired phagocytic activity of granulocytes. Reduced glutathione was significantly decreased in mice exposed to CuO NPs.


Assuntos
Cobre , Nanopartículas , Imunidade Adaptativa , Animais , Antioxidantes , Cobre/toxicidade , Citocinas , Camundongos , Nanopartículas/toxicidade , Óxidos
4.
Microorganisms ; 9(12)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34946174

RESUMO

A total of 152 aerosol and spider web samples were collected: 96 spider's webs in karst areas in 4 European countries (Czech Republic, France, Italy, and Slovakia), specifically from the surface environment (n = 44), photic zones of caves (n = 26), and inside (aphotic zones) of caves (n = 26), 56 Particulate Matter (PM) samples from the Sloupsko-Sosuvsky Cave System (speleotherapy facility; n = 21) and from aerosol collected from the nearby city of Brno (n = 35) in the Czech Republic. Nontuberculous mycobacteria (NTM) were isolated from 13 (13.5%) spider's webs: 5 isolates of saprophytic NTM (Mycobacterium gordonae, M. kumamotonense, M. terrae, and M. terrae complex) and 6 isolates of potentially pathogenic NTM (M. avium ssp. hominissuis, M. fortuitum, M. intracellulare, M. peregrinum and M. triplex). NTM were not isolated from PM collected from cave with the speleotherapy facility although mycobacterial DNA was detected in 8 (14.3%) samples. Temperature (8.2 °C, range 8.0-8.4 °C) and relative humidity (94.7%, range 93.6-96.6%) of air in this cave were relatively constant. The average PM2.5 and PM10 mass concentration was 5.49 µg m-3 and 11.1 µg m-3. Analysed anions (i.e., F-, Cl-, NO2-, SO42-, PO43- and NO3-) originating largely from the burning of wood and coal for residential heating in nearby villages in the surrounding area. The air in the caves with speleotherapy facilities should be monitored with respect to NTM, PM and anions to ensure a safe environment.

5.
Chemosphere ; 278: 130402, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33839387

RESUMO

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 (NOx, SO2, CO, CO2, 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-1 (hard coal, the oldest-type boiler), and 0.290 and 0.544 g kg-1 (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.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , China , Carvão Mineral/análise , Gases , Calefação , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
6.
Int J Mol Sci ; 21(22)2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33228049

RESUMO

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(NO3)2 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(NO3)2 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(NO3)2 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 (NF-κB) and selected cytokines, such as tumor necrosis factor alpha (TNFα), transforming growth factor beta 1 (TGFß1), interleukin 6(IL-6), IL-1α and IL-1ß , displayed a tissue-specific response to lead exposure. In summary, diminished inflammatory response in tissues after Pb(NO3)2 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.


Assuntos
Poluentes Atmosféricos/farmacocinética , Chumbo/farmacocinética , Pulmão/efeitos dos fármacos , Macrófagos Alveolares/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Nitratos/farmacocinética , Actinas/agonistas , Actinas/genética , Actinas/imunologia , Administração por Inalação , Poluentes Atmosféricos/toxicidade , Animais , Disponibilidade Biológica , Feminino , Expressão Gênica , Meia-Vida , Exposição por Inalação/análise , Interleucina-1alfa/agonistas , Interleucina-1alfa/genética , Interleucina-1alfa/imunologia , Interleucina-1beta/agonistas , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/agonistas , Interleucina-6/genética , Interleucina-6/imunologia , Chumbo/toxicidade , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/patologia , Pulmão/imunologia , Pulmão/patologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/patologia , Nanopartículas Metálicas/administração & dosagem , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/agonistas , NF-kappa B/genética , NF-kappa B/imunologia , Nitratos/toxicidade , Espectrofotometria Atômica , Distribuição Tecidual , Fator de Crescimento Transformador beta1/agonistas , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/imunologia , Fator de Necrose Tumoral alfa/agonistas , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
7.
Anal Chem ; 92(24): 15827-15836, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33237761

RESUMO

A sensitive and fast method for simultaneous determination of gaseous ammonia (NH3) and particulate ammonium (NH4+) in ambient air is presented. NH3 is sampled in a cylindrical wet effluent diffusion denuder (CWEDD) and analyzed online by a continuous flow system with a fluorescence detector (FLD), while NH4+ bound to aerosol particles is sampled in parallel by a condensation growth unit-the aerosol counterflow two-jet unit (CGU-ACTJU) sampler-and analyzed online with another FLD. The sensitive fluorescence detection of ammonium in concentrates of the CWEDD and the ACTJU is based on its reaction with ortho-phthaldialdehyde and sulfite to form isoindol-1-sulfonate. The calibration curve of ammonium is linear in the concentration range of 5 × 10-9 to 2 × 10-6 M. The limit of detection (LOD = 3 s/n) values of NH3 and NH4+ are 3.52 ng m-3 (5.05 ppt) and 1.04 ng m-3, respectively. The developed method enables online measuring of distribution of NH3/NH4+ in ambient air with a time resolution of 1 s. The optimized method was used for the determination of NH3/NH4+ in urban air in Brno in two campaigns during the winter and summer of 2018. The results obtained by the developed method were compared with a reference method based on the sampling on filters and "dry" diffusion denuders coated by phosphoric acid.

8.
J Trace Elem Med Biol ; 61: 126511, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32294608

RESUMO

OBJECTIVES: We used mice as an animal model to investigate the entry of ZnO nanoparticles from the ambient air into the lungs and other organs, subsequent changes in Zn levels and the impact on the transcription of Zn homeostasis-related genes in the lungs. METHODS: The mice were exposed to two concentrations of ZnO nanoparticles; lower (6.46 × 104 particles/cm3) and higher (1.93 × 106 particles/cm3), allowed to breathe the nanoparticles in the air for 12 weeks and subjected to necropsy. Characterization of the ZnO nanoparticles was done using transmission electron microscopy (TEM). Energy-dispersive X-ray (EDX) spectroscopy was used to quantify ZnO nanoparticles in the lungs, brain, liver and kidney. The total zinc content in the lungs, brain, liver, kidney, red blood cells and plasma was estimated by inductively coupled plasma mass spectroscopy (ICP-MS). Transcription rate of the genes was evaluated by RealTime PCR. RESULTS: The two concentration of ZnO nanoparticles in the ambient air produced two different outcomes. The lower concentration resulted in significant increases in Zn content of the liver while the higher concentration significantly increased Zn in the lungs (p < 0.05). Additionally, at the lower concentration, Zn content was found to be lower in brain tissue (p < 0.05). Using TEM/EDX we detected ZnO nanoparticles inside the cells in the lungs, kidney and liver. Inhaling ZnO NP at the higher concentration increased the levels of mRNA of the following genes in the lungs: Mt2 (2.56 fold), Slc30a1 (1.52 fold) and Slc30a5 (2.34 fold). At the lower ZnO nanoparticle concentration, only Slc30a7 mRNA levels in the lungs were up (1.74 fold). Thus the two air concentrations of ZnO nanoparticles produced distinct effects on the expression of the Zn-homeostasis related genes. CONCLUSION: Until adverse health effects of ZnO nanoparticles deposited in organs such as lungs are further investigated and/or ruled out, the exposure to ZnO nanoparticles in aerosols should be avoided or minimised.

9.
Nanomaterials (Basel) ; 10(3)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197515

RESUMO

We investigated the transcriptomic response and epigenetic changes in the lungs of mice exposed to inhalation of copper(II) oxide nanoparticles (CuO NPs) (8 × 105 NPs/m3) 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.

10.
ACS Nano ; 14(3): 3096-3120, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32105447

RESUMO

Lead oxide nanoparticles (PbONPs), upon their entry into the lungs via 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 caveolins and clathrin 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.


Assuntos
Chumbo/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Nanopartículas/metabolismo , Óxidos/metabolismo , Animais , Feminino , Chumbo/administração & dosagem , Chumbo/química , Fígado/química , Fígado/metabolismo , Pulmão/química , Pulmão/metabolismo , Proteínas de Membrana Transportadoras/química , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/administração & dosagem , Nanopartículas/química , Óxidos/administração & dosagem , Óxidos/química
11.
Nanotoxicology ; 14(2): 214-231, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31726900

RESUMO

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/m3; 1.93 × 106 particles/cm3) 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 F2-alpha and E2) 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.


Assuntos
Dano ao DNA , Exposição por Inalação/efeitos adversos , Chumbo/toxicidade , Lipídeos de Membrana/metabolismo , Nanopartículas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Óxidos/toxicidade , Animais , Biomarcadores/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Humanos , Inflamação , Exposição por Inalação/análise , Rim/efeitos dos fármacos , Rim/metabolismo , Chumbo/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/metabolismo , Oxirredução , Óxidos/metabolismo , Testes de Toxicidade Subcrônica
12.
Food Chem Toxicol ; 136: 110954, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31707033

RESUMO

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/m3, total deposited dose: 0.195 µg CdO/g body weight). CdO NPs increased percentage of thymus CD3e+CD8a+ cells and moderately enhanced splenocyte proliferation and production of cytokines and chemokines. CdO NPs elevated pro-fibrotic factors (TGF-ß2, 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.


Assuntos
Compostos de Cádmio/toxicidade , Fibrose/induzido quimicamente , Imunidade Celular/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Óxidos/toxicidade , Tíbia/efeitos dos fármacos , Administração por Inalação , Animais , Compostos de Cádmio/administração & dosagem , Citocinas/metabolismo , Feminino , Intestinos/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Linfonodos/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Camundongos Endogâmicos ICR , Óxidos/administração & dosagem , Baço/efeitos dos fármacos , Timo/efeitos dos fármacos
13.
Environ Sci Pollut Res Int ; 26(28): 29012-29019, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31388949

RESUMO

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.


Assuntos
Biocombustíveis , Gasolina , Metais/análise , Óleos , Óleo de Brassica napus , Emissões de Veículos
14.
Environ Pollut ; 253: 646-654, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31330356

RESUMO

Although plants are often exposed to atmospheric nanoparticles (NPs), the mechanism of NP deposition and their effects on physiology and metabolism, and particularly in combination with other stressors, are not yet understood. Exploring interactions between stressors is particularly important for understanding plant responses in urban environments where elevated temperatures can be associated with air pollution. Accordingly, 3-year-old spruce seedlings were exposed for 2 weeks to aerial cadmium oxide (CdO) NPs of environmentally relevant size (8-62 nm) and concentration (2 × 105 cm-3). While half the seedlings were initially acclimated to high temperature (35 °C) and vapour pressure deficit (VPD; 2.81 kPa), the second half of the plants were left under non-stressed conditions (20 °C, 0.58 kPa). Atomic absorption spectrometry was used to determine Cd content in needles, while gas and liquid chromatography was used to determine changes in primary and secondary metabolites. Photosynthesis-related processes were explored with gas-exchange and chlorophyll fluorescence systems. Our work supports the hypothesis that atmospheric CdO NPs penetrate into leaves but high temperature and VPD reduce such penetration due to stomatal closure. The hypothesis that atmospheric CdO NPs influences physiological and metabolic processes in plants was also confirmed. This impact strengthens with increasing time of exposure. Finally, we found evidence that plants acclimated to stress conditions have different sensitivity to CdO NPs compared to plants not so acclimated. These findings have important consequences for understanding impacts of global warming on plants and indicates that although the effects of elevated temperatures can be deleterious, this may limit other forms of plant stress associated with air pollution.


Assuntos
Poluentes Atmosféricos/toxicidade , Compostos de Cádmio/toxicidade , Nanopartículas/toxicidade , Óxidos/toxicidade , Picea/efeitos dos fármacos , Temperatura , Abies , Aclimatação/fisiologia , Poluentes Ambientais/metabolismo , Aquecimento Global , Temperatura Alta , Fotossíntese/fisiologia , Picea/fisiologia , Pinus , Folhas de Planta/efeitos dos fármacos , Plântula/efeitos dos fármacos
15.
Chemosphere ; 229: 51-59, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31075702

RESUMO

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 (NOx, SO2, CO, CO2, 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-1) and particulate organic compounds (sum of PAHs: 225-275 mg kg-1) 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.


Assuntos
Carvão Mineral/análise , Gases/química , Hidrocarbonetos Policíclicos Aromáticos/química , Biomassa , República Tcheca , Europa (Continente) , Calefação
16.
Nanotoxicology ; 13(7): 952-963, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31012774

RESUMO

The inhalation or application of nanoparticles (NPs) has serious impacts on immunological reactivity. However, the effects of NPs on the immune system are influenced by numerous factors, which cause a high variability in the results. Here, mice were exposed to a three month continuous inhalation of copper oxide (CuO) NPs, and at different time intervals (3, 14, 42 and 93 days), the composition of cell populations of innate and adaptive immunity was evaluated in the spleen by flow cytometry. The ability of spleen cells from exposed and control mice to respond to stimulation with T- or B-cell mitogens by proliferation and by production of cytokines IL-2, IL-6, IL-10, IL-17 and IFN-γ was characterized. The results showed that the inhalation of CuO NPs predominantly affects the cells of innate immunity (changes in the proportion of eosinophils, neutrophils, macrophages and antigen-presenting cells) with a minimal effect on the percentage of T and B lymphocytes. However, the proliferative and secretory activity of T cells was already significantly enhanced after 3 days from the start of inhalation, decreased on day 14 and normalized at the later time intervals. There was no correlation between the impacts of NPs on the cells of innate and adaptive immunity. The results have shown that the inhalation of CuO NPs significantly alters the composition of cell populations of innate immunity and modulates the proliferation and production of cytokines by cells of the adaptive immune system. However, the immunomodulatory effects of inhaled NPs strongly depend on the time of inhalation.


Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Cobre/toxicidade , Imunidade Inata/efeitos dos fármacos , Nanopartículas/toxicidade , Administração por Inalação , Animais , Cobre/administração & dosagem , Citocinas/biossíntese , Feminino , Cinética , Camundongos , Camundongos Endogâmicos ICR , Modelos Animais
17.
Ind Health ; 57(6): 741-744, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30918138

RESUMO

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.


Assuntos
Nanopartículas Metálicas/efeitos adversos , Exposição Ocupacional/efeitos adversos , Pesquisadores , Encurtamento do Telômero/efeitos dos fármacos , Adulto , Poluentes Ocupacionais do Ar/efeitos adversos , República Tcheca/epidemiologia , Feminino , Humanos , Leucócitos , Masculino , Pessoa de Meia-Idade , Óxidos
18.
Environ Sci Pollut Res Int ; 26(2): 1675-1692, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30448949

RESUMO

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 PM1 and PM10 (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 PM1 and PM10 chemical compositions to investigate their sources. During the measurement campaign, prevailing northeastern-southwestern (NE-SW) wind directions (WDs) were recorded. Higher average PM10 concentration was measured in Radvanice than in Plesná, whereas PM1 concentrations were similar at both sites. A source apportionment analysis revealed six and five sources for PM10 and PM1, 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 PM10 and 27% for PM1), which were caused by a large metallurgical complex located to the SW, and biomass burning (25% for PM10 and 36% for PM1). 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 PM10 and PM1, 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.


Assuntos
Poluição do Ar/análise , Material Particulado/análise , Cidades , República Tcheca , Monitoramento Ambiental , Tamanho da Partícula , Polônia , Vento
19.
Toxicol Sci ; 168(1): 190-200, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30500950

RESUMO

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.


Assuntos
Processamento Alternativo/efeitos dos fármacos , Nanopartículas/toxicidade , Óxido de Zinco/toxicidade , Administração por Inalação , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Feminino , Expressão Gênica/efeitos dos fármacos , Imunidade Celular/efeitos dos fármacos , Inflamação , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos ICR , Estresse Oxidativo/efeitos dos fármacos
20.
Chemosphere ; 210: 279-286, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30005349

RESUMO

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-3 and 5.5 ng m-3, 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.


Assuntos
Abietanos/análise , Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Glucose/análogos & derivados , Glucose/análise , Estações do Ano
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