OBJECTIVE: The use of nanotechnology is growing enormously and occupational physicians have an increasing interest in evaluating potential hazards and finding biomarkers of effect in workers exposed to nanoparticles. METHODS: A study was carried out with 36 workers exposed to (nano)TiO2 pigment and 45 controls. Condensate (EBC) titanium and markers of oxidation of nucleic acids (including 8-hydroxy-2-deoxyguanosine (8-OHdG), 8-hydroxyguanosine (8-OHG), 5-hydroxymethyl uracil (5-OHMeU)) and proteins (such as o-tyrosine (o-Tyr), 3-chlorotyrosine (3-ClTyr) and 3-nitrotyrosine (3-NOTyr)) were analysed from samples of their exhaled breath. RESULTS: In the production workshops, the median total mass 2012 and 2013 TiO2 concentrations were 0.65 and 0.40 mg/m(3), respectively. The median numbers of concentrations measured by the scanning mobility particle sizer (SMPS) and aerodynamic particle sizer (APS) were 1.98 × 10(4) and 2.32 × 10(4) particles/cm(3), respectively; and about 80% of those particles were smaller than 100 nm in diameter. In the research workspace, lower aerosol concentrations (0.16 mg/m(3) and 1.32 × 10(4) particles/cm(3)) were found. Titanium in the EBC was significantly higher in production workers (p<0.001) than in research workers and unexposed controls. Accordingly, most EBC oxidative stress markers, including in the preshift samples, were higher in production workers than in the two other groups. Multiple regression analysis confirmed an association between the production of TiO2 and the levels of studied biomarkers. CONCLUSIONS: The concentration of titanium in EBC may serve as a direct exposure marker in workers producing TiO2 pigment; the markers of oxidative stress reflect the local biological effect of (nano)TiO2 in the respiratory tract of the exposed workers.

• MeSH
• biologické markery metabolismus   MeSH
• dechové testy MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• nanočástice škodlivé účinky   MeSH
• nukleové kyseliny metabolismus   MeSH
• oxidace-redukce MeSH
• oxidační stres účinky léků   MeSH
• pevné částice škodlivé účinky   MeSH
• poškození DNA MeSH
• práce MeSH
• pracovní expozice škodlivé účinky   MeSH
• proteiny metabolismus   MeSH
• titan škodlivé účinky   MeSH
• velikost částic MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The health effects of engineered nanoparticles in humans are not well-understood; however experimental data support the theory of oxidative stress promoting fibrogenesis and carcinogenicity. The aim of this study was to detect TiO2 particles in exhaled breath condensate (EBC) and urine samples to ascertain their presence and potential persistence and excretion in urine.EBC and urine samples were collected from 20 workers exposed to TiO2 aerosol; among them, 16 had a higher risk level of exposure (production workers) and four had medium risk level (research workers); in addition to 20 controls. Titanium levels in EBC and urine were analysed using the inductively coupled plasma mass spectrometry (ICP-MS) method. A Raman microspectroscopic analysis was performed in EBC and urine to identify the phase composition of TiO2 particles observed. Aerosol exposure in the workplaces was measured using SMPS and APS spectrometers and P-TRAK and DustTRAK DRX monitors.The median concentration of TiO2 aerosol was 1.98 × 10(4) particles cm(-3), the interquartile range (IQR) was 1.50 × 10(4) - 3.01 × 10(4) particles cm(-3) and the median mass concentration was 0.65 mg m(-3) (IQR 0.46-.0.83 mg m(-3)); 70-82% of the particles were smaller than 100 nm in diameter. In any part of the plant, the median TiO2 air concentration did not exceed the national airborne exposure limit of 10 mg m(-3) for inert dust. Particles of rutile and/or anatase were found in the EBC of exposed workers in 8/20 (40%) of the pre-shift and 14/20 (70%) of the post-shift samples. In the urine of workers, TiO2 particles were detected in 2/20 post-shift urine samples only. The mean concentration of titanium in the EBC in production workers was 24.1 ± 1.8 μg/l. In the research workers the values were below the limit of quantitation; LOQ = 4.0 ± 0.2 μg/l), as well as in the controls. In the urine samples of all of the subjects, titanium was under the limit of detection (LOD = 1.2 μg/l). Raman microanalysis of EBC in the workers confirmed the presence of TiO2 anatase and/or rutile crystal phases in the pre-shift samples and their persistence from previous shifts in the workers.

• MeSH
• dechové testy MeSH
• dospělí MeSH
• lidé MeSH
• oxidační stres účinky léků   MeSH
• pracovní expozice * MeSH
• průřezové studie MeSH
• Ramanova spektroskopie metody   MeSH
• titan analýza   moč   MeSH
• vydechnutí MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

OBJECTIVES: Experimental studies using nanoscale TiO2 have documented lung injury, inflammation, oxidative stress, and genotoxicity. Human health data are extremely scarce. METHODS: In exhaled breath condensate (EBC) and urine of 22 office employees occupationally exposed to TiO2 during their visit in the production workshops for average 14±9 min/day a panel of biomarkers of nucleic acids and proteins oxidation was studied, specifically 8-hydroxy-2-deoxyguanosine (8-OHdG), 8-hydroxyguanosine (8-OHG), 5-hydroxymethyl uracil (5-OHMeU), o-tyrosine (o-Tyr), 3-chlorotyrosine (3-ClTyr), and 3-nitrotyrosine (3-NOTyr). Examination was performed also in 14 comparable controls. RESULTS: The median respirable TiO2 mass concentration in the workshops was 0.40 mg/m3, median number concentration was 2.32×104 particles/cm3 with 80% of the particles being <100 nm in diameter. All 6 markers of oxidation were elevated in EBC in factory office employees relative to controls (p<0.01). Significant association was found between their job in TiO2 production plant and 5 markers of oxidation (except 3-NOTyr) in the EBC in multivariate analysis. No elevation of markers was detected in the urine. CONCLUSION: This pilot study suggests that even short nanoTiO2 exposure may lead to pulmonary oxidative stress; however this effect may be short-term and reversible. The clinical significance of these findings is unclear and more studies are needed.

• MeSH
• dospělí MeSH
• kovové nanočástice škodlivé účinky   MeSH
• látky znečišťující vzduch škodlivé účinky   MeSH
• lidé středního věku MeSH
• lidé MeSH
• nemoci z povolání krev   MeSH
• oxidační stres * MeSH
• pilotní projekty MeSH
• pracovní expozice škodlivé účinky   MeSH
• titan škodlivé účinky   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

OBJECTIVE: Nanomaterials are materials consisting of particles having one or more dimensions smaller than 100 nm. Nanoparticles (NP) have different properties and effects in comparison with the same particle materials of larger size. They can penetrate through various membranes and get from the bloodstream to other organs in the body. Therefore, in our experiment we have dealt with the impact of nanoparticles TiO2 instilled intravenously (i.v.) (to a tail vein of an animal) on the selected parameters of bronchoalveolar lavage (BAL). The aim of our study was to determine whether TiO2 nanoparticles do pass through the vascular system to the respiratory tract, and if so, how they affect the selected inflammatory and cytotoxic parameters of bronchoalveolar lavage. METHODS: Wistar rats were intravenously given a suspension of TiO2 nanoparticles in saline solution. This suspension contained 10% volume of rat serum in dose: 1.0% from LD50 = 0.592 mg/kg of animal body weight. After the time intervals 1, 7, 14 and 28 days, the animals were sacrificed under anaesthesia; bronchoalveolar lavage was performed and the BAL cells were isolated. We have examined these markers: differential count of BAL cells - alveolar macrophages (AM), polymorphonuclear leukocytes (PMNL), lymphocytes (Ly); viability and phagocytic activity of AM; proportion of immature cells and cathepsin D enzyme levels. RESULTS: Regarding the respiratory toxicity of TiO2 nanoparticles we have found that TiO2 nanoparticles are relatively inert. BAL examined parameters (except the immature form of AM) were not significantly changed after 28 days of instillation compared to the control group. We found that the TiO2 nanoparticles used in our study were transferred from the bloodstream to the respiratory tract, but in a 28-day phase after i.v. instillation have been largely eliminated by the defence mechanism from the respiratory tract. CONCLUSIONS: We suggest low biopersistence and relatively rapid elimination of TiO2 nanoparticles from the lung under used experimental conditions.

• MeSH
• bronchoalveolární lavážní tekutina chemie   MeSH
• intravenózní podání MeSH
• kovové nanočástice aplikace a dávkování   toxicita   MeSH
• krysa rodu rattus MeSH
• potkani Wistar MeSH
• titan aplikace a dávkování   toxicita   MeSH
• velikost částic MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Titanium oxide (TiO2) and iron oxide (α-Fe2O3) hematite films have potential applications as photoanodes in electrochemical water splitting. In the present work TiO2 and α-Fe2O3 thin films were prepared by two methods, e.g., sol-gel and High Power Impulse Magnetron Sputtering (HiPIMS) and judged on the basis of physical properties such as crystalline structure and surface topography and functional properties such as simulated photoelectrochemical (PEC) water splitting conditions. It was revealed that the HiPIMS method already provides crystalline structures of anatase TiO2 and hematite Fe2O3 during the deposition, whereas to finalize the sol-gel route the as-deposited films must always be annealed to obtain the crystalline phase. Regarding the PEC activity, both TiO2 films show similar photocurrent density, but only when illuminated by UV light. A different situation was observed for hematite films where plasmatic films showed a tenfold enhancement of the stable photocurrent density over the sol-gel hematite films for both UV and visible irradiation. The superior properties of plasmatic film could be explained by ability to address some of the hematite drawbacks by deposition of very thin films (25 nm) consisting of small densely packed particles and by doping with Sn.

• MeSH
• difrakce rentgenového záření MeSH
• elektřina MeSH
• elektrochemie * MeSH
• fotochemie * MeSH
• mikroskopie elektronová rastrovací MeSH
• Ramanova spektroskopie MeSH
• titan chemie   MeSH
• voda chemie   MeSH
• železité sloučeniny chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In the present study, the coupling of adsorption capacity and photocatalytic efficiency of two different industrially produced titania catalysts was investigated and compared. The azo dye Reactive Red 195 was selected as a model compound. The tested catalysts, PK-10 and PK-180, exhibited different adsorption capacities due to their significant difference in their specific surface, but both have proven to be effective photocatalysts for photodegradation of the studied dye. PK-10 exhibited strong adsorption of the studied dye due to its high specific surface area, while the second studied catalyst, PK-180, demonstrated negligible adsorption of Reactive Red 195. The effect of the pH, the concentration of the catalyst and the initial concentration of the dye appear to affect the photocatalytic rate. The effect of the presence of humic acids and inorganic ions was also examined, while the contribution of various reactive species was indirectly evaluated through the addition of various scavengers. To evaluate the extent of mineralisation of the studied dye, total organic carbon (TOC) measurements during the experiment were also conducted. Besides total colour removal, evident reduction of TOC was also achieved using both catalysts.

• MeSH
• adsorpce MeSH
• anionty MeSH
• azosloučeniny izolace a purifikace   účinky záření   MeSH
• chemické látky znečišťující vodu izolace a purifikace   účinky záření   MeSH
• čištění vody metody   MeSH
• fotolýza MeSH
• huminové látky analýza   MeSH
• katalýza MeSH
• koncentrace vodíkových iontů MeSH
• naftalensulfonany izolace a purifikace   účinky záření   MeSH
• nanočástice chemie   MeSH
• scavengery volných radikálů chemie   MeSH
• titan chemie   MeSH
• ultrafialové záření * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

TiO2 along with nano-TiO2 are commonly found in consumer products. In vivo studies have observed an accumulation of nano-TiO2 in macrophages. However, characteristics of nano-TiO2 determining toxicity remain unclear. In our study, the cytotoxic effects of 14 diverse nano-TiO2 on THP-1 macrophage-like cells were measured by 3 cytotoxicity assays (MTS, WST-1 and LDH). Total averaged cytotoxicity was calculated using principal component analysis. Characteristics of all 14 nano-TiO2 included hydrodynamic diameter, zeta potential, shape, polydispersity index (PDI) and concentration; moreover, crystal form, specific surface area and crystallite size were measured for 10 nano-TiO2.The variables affecting cytotoxicity were chosen using LASSO (least absolute shrinkage and selection operator). Except for concentration, PDI in media measured within 1 h after preparation of the nanomaterial dispersion was selected as a variable affecting cytotoxicity: stable dispersion resulted in higher cytotoxic effects. Crystallite size has been shown to have nonlinear effects (particles of sizes between 20 and 60 nm were cytotoxic while smaller and larger ones were not) and thus it has been excluded from LASSO. The shape (particles/fibre) and crystal form did not affect the cytotoxicity. PDI and the nonlinear effect of size could be an explanation for the inconsistencies of the cytotoxicity of nano-TiO2 in various studies.

• MeSH
• endotoxiny analýza   MeSH
• kultivační média MeSH
• lidé MeSH
• makrofágy účinky léků   MeSH
• nanočástice chemie   toxicita   MeSH
• povrchové vlastnosti MeSH
• THP-1 buňky MeSH
• titan chemie   toxicita   MeSH
• velikost částic MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

The paper addresses laboratory preparation, characterization and in vitro evaluation of antibacterial activity of graphite/TiO2 nanocomposites. Composites graphite/TiO2 with various ratio of TiO2 nanoparticles (30wt.%, and 50wt.%) to graphite were prepared using a thermal hydrolysis of titanylsulfate in the presence of graphite particles, and subsequently dried at 80°C. X-ray powder diffraction, transmission electron microscopy and Raman microspectroscopy served as phase-analytical methods distinguishing anatase and rutile phases in the prepared composites. Scanning and transmission electron microscopy techniques were used for characterization of morphology of the prepared samples. A developed modification of the standard microdilution test was used for in vitro evaluation of daylight induced antibacterial activity, using four common human pathogenic bacterial strains (Staphylococcus aureus, Escherichia coli, Enterococcus faecalis and Pseudomonas aeruginosa). Antibacterial activity of the graphite/TiO2 nanocomposites could be based mainly on photocatalytic reaction with subsequent potential interaction of reactive oxygen species with bacterial cells. During the antibacterial activity experiments, the graphite/TiO2 nanocomposites exhibited antibacterial activity, where differences in the onset of activity and activity against bacterial strains were observed. The highest antibacterial activity evaluated as minimum inhibitory concentration was observed against P. aeruginosa after 180min of irradiation.

• MeSH
• antibakteriální látky chemie   farmakologie   MeSH
• Bacteria účinky léků   účinky záření   MeSH
• grafit chemie   MeSH
• lidé MeSH
• nanočástice chemie   MeSH
• světlo * MeSH
• titan chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Human health data regarding exposure to nanoparticles are extremely scarce and biomonitoring of exposure is lacking in spite of rodent pathological experimental data. Potential markers of the health-effects of engineered nanoparticles were examined in 30 workers exposed to TiO2 aerosol, 22 office employees of the same plant, and 45 unexposed controls. Leukotrienes (LT) B4, C4, E4, and D4 were analysed in the exhaled breath condensate (EBC) and urine via liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). Fractional exhaled nitric oxide (FeNO) and spirometry was also measured. The median particle number concentration of the aerosol in the production ranged from 1.98 × 10(4) to 2.32 × 10(4) particles cm(-3); about 80% of the particles were <100 nm in diameter. Median total mass concentration varied between 0.4 and 0.65 mg m(-3). All LT levels in workers' EBC were elevated relative to the controls (p < 0.01). LTs in the EBC sample were correlated with titanium levels. Urinary LTs were not elevated in the workers and office employees. Office workers had higher LTB4 in EBC (p < 0.05), and higher levels of FeNO (p < 0.01). FeNO was higher in office employees with allergic diseases and was negatively correlated with smoking (p < 0.01). In spirometry significant impairment in the workers was seen only for %VCIN and %PEF (both p < 0.01). Multiple regression analysis confirmed a significant association between production of TiO2 and all cysteinyl LTs in EBC (p < 0.01) and impaired %VCIN and %PEF (both p < 0.01). LTB4 was also associated with smoking (p < 0.01). LT levels complemented our earlier findings of DNA, protein, and lipid damage in the EBC of workers with nanoTiO2 exposures. Cysteinyl LTs in EBC analysis suggest inflammation and potential fibrotic changes in the lungs; they may be helpful for monitoring the biological effect of (nano)TiO2 on workers. Spirometry was not sensitive enough.

• MeSH
• aerosoly analýza   MeSH
• biologické markery analýza   MeSH
• dechové testy metody   MeSH
• dospělí MeSH
• koncentrace vodíkových iontů MeSH
• leukotrieny analýza   moč   MeSH
• lidé MeSH
• nanočástice škodlivé účinky   MeSH
• oxid dusnatý analýza   MeSH
• pracoviště MeSH
• pracovní expozice analýza   MeSH
• regresní analýza MeSH
• respirační funkční testy MeSH
• studie případů a kontrol MeSH
• tandemová hmotnostní spektrometrie MeSH
• titan škodlivé účinky   MeSH
• vydechnutí * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

OBJECTIVE: Nanomaterials consist of particles smaller than 100 nm - nanoparticles (NPs). Their nano dimensions allow them to penetrate through various membranes and enter into the bloodstream and disseminate into different body organs. Massive expansion of nanotechnologies together with production of new nanoparticles which have not yet been in contact with living organisms may pose a potential health problem. It is therefore necessary to investigate the health impact of NPs after experimental exposure. Comparison of the effect of TiO2 and NPs Fe3O4 in Wistar rats at time intervals 1, 7, 14 and 28 days was performed by studying the cytotoxic effect in the isolated inflammatory cells from bronchoalveolar lavage (BAL). METHODS: Wistar rats were intravenously (i.v.) given a suspension of NPs TiO2 or Fe3O4 (coated by sodium oleate) via the tail vein. After time intervals of 1, 7, 14 and 28 days, we sacrificed the animals under anaesthesia, performed BAL and isolated the cells. The number of animals in the individual groups was 7-8. We examined the differential count of BAL cells (alveolar macrophages - AM, polymorphonuclear leukocytes - PMN, lymphocytes - Ly); viability and phagocytic activity of AM; the proportion of immature and polynuclear cells and enzymes - cathepsin D - CAT D, lactate dehydrogenase - LDH and acid phosphatase - ACP. RESULTS: We found that TiO2 NPs are relatively inert - without induction of inflammatory and cytotoxic response. Exposure to nanoparticles Fe3O4 induced - under the same experimental conditions - in comparison with the control and TiO2 a more extensive inflammatory and cytotoxic response, albeit only at 1, 7 and 14 days after injection. CONCLUSIONS: The results suggest that TiO2 and Fe3O4 nanoparticles used in our study were transferred from the bloodstream to the respiratory tract, but this effect was not observed at 28 days after i.v. injection, probably due to their removal from the respiratory tract.

• MeSH
• intravenózní podání MeSH
• kovové nanočástice aplikace a dávkování   toxicita   MeSH
• krysa rodu rattus MeSH
• nemoci dýchací soustavy chemicky indukované   MeSH
• oxid železnato-železitý aplikace a dávkování   toxicita   MeSH
• potkani Wistar MeSH
• titan aplikace a dávkování   toxicita   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH