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Szigeti T.,Eötvös Loránd University | Szigeti T.,Hungarian Satellite Trace Elements Institute to UNESCO | Kertesz Z.,Hungarian Academy of Sciences | Dunster C.,King's College London | And 5 more authors.
Atmospheric Environment | Year: 2014

Fifty samples of indoor and outdoor PM2.5 were collected onto quartz fiber and Teflon membrane filters in five office buildings equipped with heating, ventilation and air-conditioning system for 8h daily in order to coincide with the work shift of employees. Samples were analyzed for i) mass concentration; ii) elemental concentration; and iii) oxidative potential (OP) through antioxidant depletion. The PM2.5 mass concentration exceeded the annual mean guideline of 10μgm-3 WHO in 50% of the samples. Indoor and outdoor PM2.5 mass concentrations correlated almost linearly. Proton-induced X-ray emission (PIXE) spectrometry was used for the monitoring of 21 elements. Quantitative determination was achieved in the case of Teflon filters only for Al, Si, S, Cl, K, Ca, Ti, Cr, Mn, Fe and Zn at ngm-3 concentration level. Quartz fiber filters were less adequate for the PIXE measurements due to their greater thickness and filamentary structure. Ca, Cr, Zn and Ti had generally higher concentration (mgg-1) indoors. Indoor/outdoor (I/O) OP values were higher than one in 14% and 57% of the samples in the case of ascorbate and reduced glutathione (GSH), respectively. Spatial and temporal variations of OP were observed across the office buildings. The I/O ratios for OP, Cr and Zn concentrations in the case of GSH were higher for three buildings. Significant relationship was observed between GSH oxidation and Cr and Zn concentrations. Thus, employees were exposed to a higher extent to reactive oxygen species in three buildings. © 2014 Elsevier Ltd.


Mihucz V.G.,Eötvös Loránd University | Mihucz V.G.,Hungarian Satellite Trace Elements Institute to UNESCO | Szigeti T.,Eötvös Loránd University | Szigeti T.,Hungarian Satellite Trace Elements Institute to UNESCO | And 10 more authors.
Microchemical Journal | Year: 2015

An integrated approach has been developed for the multi-component analysis of indoor PM2.5 collected onto the same quartz fiber filter (QFF) by using an innovative combination of techniques such as inductively coupled sector field plasma mass spectrometry (ICP-SF-MS) with vapor-phase microwave-assisted aqua regia or sonication-assisted water extraction, ion chromatography, thermal-optical transmittance as well as high performance liquid chromatography and enzyme-linked 5,5'-dithio-bis(2-nitrobenzoic acid) assay for the determination of elemental composition, major inorganic ions, elemental/organic carbon (EC/OC) as well as oxidative potential (OP) through ascorbate (AA) and reduced glutathione (GSH) depletion, respectively. The low mass of PM2.5 collectable indoors, the elemental blank values of the QFFs and the sample volume/acidity requirements of the ICP-SF-MS represented a challenge for elemental determination. Finally, this approach was successfully applied for determination of 15 elements (Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Rb, Sr, Mo, Cd, Sn and Pb) at the ngm-3 level in more than two-thirds of indoor PM2.5 (n=25) collected in mechanically ventilated offices within the European Union project OFFICAIR at increased sampling flow rates (0.6m3h-1-2.3m3h-1) and sampling time (cca. 100h) in the acidic/aqueous extracts. The concentration of Cl-, NO3-, SO42-, Na+, NH4+, K+, Ca2+, Mg2+, OC and EC was at the μgm-3 level in the aqueous extracts. This new approach aiming at the comprehensive characterization of low mass indoor PM2.5 samples allowed assessment of OPAA and OPGSH in all samples. The PM2.5 critical sample mass to achieve elemental determination was approximately 400μg. © 2014 Elsevier B.V.


Szigeti T.,Eötvös Loránd University | Szigeti T.,Hungarian Satellite Trace Elements Institute to UNESCO | Ovari M.,Eötvös Loránd University | Ovari M.,Hungarian Satellite Trace Elements Institute to UNESCO | And 5 more authors.
Science of the Total Environment | Year: 2015

A comprehensive chemical characterization and oxidative potential (OP) assessment of PM2.5 was carried out at an urban site of Budapest between June 2010 and May 2013 to investigate the seasonal variability of particulate phase air pollutants and their oxidative activity. Chemical analyses included the determination of the concentration of trace elements, major water-soluble inorganic ions and carbonaceous fractions (total carbon, water-soluble organic carbon, organic carbon, elemental carbon). The OP of PM2.5 was assessed by antioxidant depletion using a synthetic respiratory tract lining fluid containing ascorbate, reduced glutathione and urate. The mean PM2.5 mass concentration (21.0μgm-3) was just below the 25μgm-3 annual mean PM2.5 limit value set by the European Commission and showed a seasonal pattern with higher levels during winter. On average, 84% of the gravimetric mass could be reconstructed by the chemical measurements. Organic matter and secondary inorganic ions were the most dominant PM2.5 constituents contributing 40 and 29% of its mass, respectively. Changes in the yearly concentrations were not identified for the investigated compounds between 2010 and 2013. Temporal differences in both ascorbate and glutathione oxidation could be observed during the 3-year long sampling period; however, no clear seasonal trend was apparent. OP metrics were associated mainly with traffic-related trace elements; however, other PM sources (i.e., long-range transport, secondary aerosol formation) could also contribute to particulate OP in Budapest. The weak correlation between OP metrics and PM2.5 mass concentration suggests the possibility of using OP as an additional metric in epidemiology. © 2015 Elsevier B.V.


Majer Z.,Eötvös Loránd University | Bosze S.,MTA ELTE Research Group of Peptide Chemistry | Szabo I.,MTA ELTE Research Group of Peptide Chemistry | Mihucz V.G.,Eötvös Loránd University | And 9 more authors.
Microchemical Journal | Year: 2015

In vitro antitumor efficacy of several dinuclear bridgings and one chelate structure dirhodium(II) complex of N-protected phenylalanine derivatives were tested on HT-29 cells. The following synthesized and previously characterized complexes were applied in the present work: Rh2(OAc)4-n(O-Phe-Z)n (n=1-4, -O-Phe-Z=N-benzyloxycarbonyl-l-phenylalaninate), Rh2(OAc)4-n(O-Phe-Ac)n (n=1-4, -O-Phe-Ac=N-acetyl-l-phenylalaninate), Rh2(OAc)2(N-Me-D-Phe-O)2 corresponding to N-methyl-d-phenylalaninate as well as Rh2(OAc)4 (-OAc=acetate). Depending on the complex ligand type and its coordination number, the intracellular rhodium (Rh) content determined by total reflection X-ray fluorescence (TXRF) spectrometry in the HT-29 cells varied between 25 and 2500ng/106 cells. In vitro cytotoxicity and cytostatic evaluations of the compounds on HT-29 human cell culture were performed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium assay. Compared to Rh2(OAc)4, the Rh compounds containing one or two -O-Phe-Z moieties proved to be the most effective on the HT-29 cells. Moreover, synchrotron radiation TXRF-X-ray absorption near edge structure measurements suggested a change of the molecular symmetry of the dirhodium(II) center for the moderately in vitro cytotoxic, lipophilic l-phenylalanine derivative complexes, characterized also by low ligand exchange rate when they were studied on HT-29 cells. © 2015 Elsevier B.V.


Mihucz V.G.,Eötvös Loránd University | Mihucz V.G.,Hungarian Satellite Trace Elements Institute to UNESCO | Silversmit G.,Ghent University | Szaloki I.,Budapest University of Technology and Economics | And 10 more authors.
Food Chemistry | Year: 2010

Extraction of As, Cd, Cu, Mn, Ni and Ti from two white as well as from one brown rice samples was studied by inductively coupled plasma sector field mass spectrometry (ICP-SF-MS). Samples were subjected to cold and hot water extraction (rice mass to deionised water volume ratio = 1:6, and 1:3, respectively). The discarded liquids were freeze-dried and digested by microwave-assisted digestion. About 50% of the content of the investigated elements could be extracted from the white rice. In case of the brown rice, the boiling water contained As, Cd, Ni and Ti in significant percentages. Elemental distributions in the rice grains determined by synchrotron radiation confocal micro-X-ray fluorescence analysis revealed that a surface layer having a thickness of about 80 μm is the richest region in elements. Ti was detectable only in this so-called skin region. Good correlation was observed for the extraction of As, Mn, Ni and Ti by the above-mentioned two techniques. Thus, in regions affected by heavy metal and other toxic element contamination, those rice dishes would be preferred whose preparation should need abundant amounts of water for washing and cooking, which later should be discarded. © 2009 Elsevier Ltd. All rights reserved.


Mihucz V.G.,Eötvös Loránd University | Zaray G.,Hungarian Satellite Trace Elements Institute to UNESCO
Comprehensive Analytical Chemistry | Year: 2016

Given that people may spend more than 90% of their time in enclosed spaces, the investigation of indoor air quality is of paramount importance. Indoor air pollutants such as ozone (O3), nitrogen oxides and volatile organic compounds (VOCs) are linked to outdoor sources. Monoterpenes, such as α-pinene and d-limonene, commonly found indoors have a propensity for oxidation in the air resulting in harmful gaseous products and secondary organic aerosol. Decreased ventilation results in low outdoor air infiltration rates, but the concentration of O3-reactive VOCs increases simultaneously. Chemical compounds in ambient particulate matter (PM) are capable of generating reactive oxygen species causing cellular damage via oxidative stress. Thus, this chapter focuses on sampling strategies for indoor air pollutants and analytical techniques used for their characterisation. Recent advances in terpene oxidation related to indoors is hereby presented. Assessment of oxidative potential of PM and linkage with its constituents are also reviewed. © 2016 Elsevier B.V.


Mihucz V.G.,Eötvös Loránd University | Mihucz V.G.,Hungarian Satellite Trace Elements Institute to UNESCO | Zaray G.,Eötvös Loránd University | Zaray G.,Hungarian Satellite Trace Elements Institute to UNESCO
Applied Spectroscopy Reviews | Year: 2016

Interest in studying leaching of toxic (in)organic contaminants such as antimony (Sb) and phthalate esters into drinking water increased because of the ever growing market of water bottled in polyethylene terephthalate (PET) packaging material. Possible contamination sources of drinking water contained in PET bottles are hereby reviewed. Instrumental analytical methods suitable for Sb and phthalate ester determination in drinking water and PET material are also presented. Outcomes on leaching of Sb and phthalate esters into drinking water are grouped according to storage time, exposure to heat/light, sample pH, and PET bottle volume. Methods for estimation of toxicological activity of water in PET bottles are also compiled. Normally, Sb and phthalate ester concentrations in drinking water do not exceed the health limit values in force. Although excellent detection limits can be achieved for phthalate ester determination, due to their ubiquity, results are primarily affected by laboratory cross-contamination. Recent investigations suggest that drinking water stored in PET bottles does not possess either genotoxic or estrogenic activity. © 2016 Taylor & Francis Group, LLC.

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