“Serum bromine levels in psoriasis”. Shani J, Barak S, Ram M, Levi D, Pfeifer Y, Schlesinger T, Avrach WW, Robberecht H, Van Grieken R, Pharmacology 25, 297 (1982). http://doi.org/10.1159/000137756
Abstract: Serum bromine levels in psoriatic Danes increased 2- to 3-fold during a 4-week bathing course in the Dead Sea. This increase correlated well with the improvement in their clinical and psychic condition. Serum bromine levels in psoriatic Danes were somewhat lower than those in healthy subjects residing in Denmark, but the difference was not significant. Israelis working in the open air in the Dead Sea area (air bromine 20-fold higher than in Jerusalem) had higher bromine levels than psoriatic or healthy Israelis residing in Jerusalem or healthy Israelis working in air-conditioned rooms in the Dead Sea area (p < 0.05), but those levels were still within the normal range. As our animal experimentation indicates that the skin is a major target organ for 82Br, applied either by bathing or as an aerosol, we conclude that the higher bromine levels noticed in the psoriatic Danes after their 4-week stay at the Dead Sea may be equally due to their contact with the bromine-containing aerosol and the high bromine level of the Dead Sea waters.
Keywords: A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1159/000137756
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“Airborne particulate matter and BTEX in office environments”. Horemans B, Worobiec A, Buczyńska A, van Meel K, Van Grieken R, Journal of environmental monitoring 10, 867 (2008). http://doi.org/10.1039/B804475A
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1039/B804475A
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“Localization of lead and fluoride in cultured tooth germs by laser microprobe mass analysis”. Vandeputte DF, Ameloot PC, Cleymaet R, Coomans D, Van Grieken RE, Biological trace element research 23, 133 (1990). http://doi.org/10.1007/BF02917184
Abstract: Trace elements can influence dental health, possibly by altering tooth resistance during preeruptive development. Therefore, it was investigated whether lead and fluoride would be incorporated into the calcifying matrices or the cellular parts of tooth germs in vitro. Using laser microprobe mass analysis, the localization of lead and fluoride was studied in the different layers or tooth germs that had been cultured in a medium to which PbCl2 of NaF had been added in different concentrations. Both elements could only be detected in the dentine layer. Hence, the enamel organ in the secretory stage of tooth development excludes lead and fluoride from the enamel, even when enamel formation by the ameloblasts is visibly disturbed. Furthermore, there seemed to be a process of saturation in the accumulation of lead and fluoride in the dentine.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/BF02917184
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“Quantification of the impact of macrophytes on oxygen dynamics and nitrogen retention in a vegetated lowland river”. Desmet NJS, van Belleghem S, Seuntjens P, Bouma TJ, Buis K, Meire P, Physics and chemistry of the earth, parts A/B/C 36, 479 (2011). http://doi.org/10.1016/J.PCE.2008.06.002
Abstract: When macrophytes are growing in the river, the vegetation induces substantial changes to the water quality. Some effects are the result of direct interactions, such as photosynthetic activity or nutrient uptake, whereas others may be attributed to indirect effects of the water plants on hydrodynamics and river processes. This research focused on the direct effect of macrophytes on oxygen dynamics and nutrient cycling. Discharge, macrophyte biomass density, basic water quality, dissolved oxygen and nutrient concentrations were in situ monitored throughout the year in a lowland river (Nete catchment, Belgium). In addition, various processes were investigated in more detail in multiple ex situ experiments. The field and aquaria measurement results clearly demonstrated that aquatic plants can exert considerable impact on dissolved oxygen dynamics in a lowland river. When the river was dominated by macrophytes, dissolved oxygen concentrations varied from 5 to 10 mg l−1. Considering nutrient retention, it was shown that the investigated in-stream macrophytes could take up dissolved inorganic nitrogen (DIN) from the water column at rates of View the MathML source. And DIN fluxes towards the vegetation were found to vary from 0.03 to 0.19 g N ha−1 h−1 in spring and summer. Compared to the measured changes in DIN load over the river stretch, it means that about 313% of the DIN retention could be attributed to direct nitrogen uptake from the water by macrophytes. Yet, the role of macrophytes in rivers should not be underrated as aquatic vegetation also exerts considerable indirect effects that may have a greater impact than the direct fixation of nutrients into the plant biomass.
Keywords: A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
DOI: 10.1016/J.PCE.2008.06.002
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“SnIV-containing layered double hydroxides as precursors for nano-sized ZnO/SnO2 photocatalysts”. Seftel EM, Popovici E, Mertens M, Stefaniak EA, Van Grieken R, Cool P, Vansant EF, Applied catalysis : B : environmental 84, 699 (2008). http://doi.org/10.1016/J.APCATB.2008.06.006
Abstract: Sn4+-containing LDH was prepared using the co-precipitation method at constant pH, and characterized using X-ray diffraction, UVvis diffuse reflectance spectroscopy and TG/DTG methods. The obtained product was further exposed to different thermal treatments in order to obtain nano-sized coupled ZnO/SnO2 systems with enhanced photocatalytic performances than the ones obtained by mixing the two semiconductor oxides. The formation of a well-defined ZnO/SnO2 system and the crystallite size, fully investigated using XRD, micro-Raman scattering and UVvis DR techniques, were found to be influenced by the nature of the precursors and the calcination temperature. The photocatalytic activity of the ZnO/SnO2 systems, evaluated for the photodegradation of methyl orange (MO) dye, was studied as a function of the initial pH, catalyst loading and the calcination temperature. The metal dispersion supplied by layered structures proved to be an advantage when preparing coupled ZnO/SnO2 systems, the photocatalytic activity being 2.3 times higher comparing with the physical mixtures performances. The maximum photocatalytic activity of the coupled ZnO/SnO2 system having a layered precursor was observed when using neutral pH, at a catalyst loading of 1 g/L calcined at 600 °C for 4 h.
Keywords: A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.APCATB.2008.06.006
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“Atmospheric deposition as decay factor for the Demeter sanctuary ruins in the industrial atmosphere of Eleusis, Greece”. Moropoulou A, Bisbikou K, Torfs K, Van Grieken R, Environmental technology 19, 1039 (1998). http://doi.org/10.1080/09593331908616761
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/09593331908616761
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“Correlation between aerosols, deposits, and weathering crusts on ancient marbles”. Moropoulou A, Bisbikou K, Van Grieken R, Torfs K, Polikreti K, Environmental technology 22, 607 (2001). http://doi.org/10.1080/09593332208618236
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/09593332208618236
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“A new method for the evaluation of the reversible and irreversible fouling propensity of MBR mixed liquor”. Huyskens C, Brauns E, van Hoof E, de Wever H, Journal of membrane science 323, 185 (2008). http://doi.org/10.1016/J.MEMSCI.2008.06.021
Abstract: In this paper, a new fouling measurement method is presented as a pragmatic approach to determine a mixed liquor's fouling propensity. The MBR-VFM (VITO Fouling Measurement) uses a specific measurement protocol consisting of alternating filtration and physical cleaning steps, which enables the calculation of both the reversible and the irreversible fouling resistances. The MBR-VFM principle, set-up and measurement protocol are described as well as the evaluation of the fouling measurement method. Finally, the MBR-VFM was validated by comparing the fouling propensity measured on-line by the MBR-VFM in a lab-scale MBR with the fouling of the MBR membranes themselves. Our experiments indicated that the MBR-VFM can accurately measure fouling and that it can even be detected earlier than can be seen from the on-line filtration data of the lab-scale system itself. Furthermore, the differences measured in reversible and irreversible fouling seemed to be related to the observed impact of physical and chemical cleaning respectively. Therefore, the application of the MBR-VFM as an on-line sensor in an advanced control system, enabling the deployment of the measured fouling data for the control of membrane cleaning, seems feasible and will be tested in the near future.
Keywords: A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
DOI: 10.1016/J.MEMSCI.2008.06.021
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“Analysis of indoor gaseous formic and acetic acid, using radial diffusive samplers”. Stranger M, Potgieter-Vermaak S, Sacco P, Quaglio F, Pagani D, Cocheo C, Godoi AFL, Van Grieken R, Environmental monitoring and assessment 149, 411 (2009). http://doi.org/10.1007/S10661-008-0217-6
Abstract: A diffusive sampling method for the determination of gaseous acetic and formic acids, using a radial symmetry diffusive sampler, has been optimised for a 7-day exposure time in this study. Sampling rate determinations were performed on data obtained from a dynamic exposure chamber, simulating the indoor conditions of an empty, closed, room, at room temperature and minimal wind speed. Analysis has been performed by means of ion chromatography. The sampling rates for formic acid concentrations of 128 ìg m−3 and 1248 ìg m−3 were determined to be 91.2 ± 3.9 ml min−1 and 111.6 ± 2.8 ml min−1, respectively. The acetic acid sampling rate was independent of the concentration in the range 160 ìg m−31564 ìg m−3, and amounted to 97.3 ± 3.1 ml min−1. Experimentally determined sampling rates showed deviations of 3% for acetic acid, and 321% for formic acid, in relation to theoretically derived values. The blank values were as low as 1.69 ± 0.07 ìg for formic acid and 1.21 ± 0.14 ìg for acetic acid, and detection limits lower than 0.5 ìg m−3 could be achieved, which is an improvement of 9899% compared to previously validated diffusive sampling methods. This study describes the first step of an extended validation program in which the applicability of these types of samplers for the measurement of organic acids will be validated and optimised for the environmental conditions typical for museum showcases.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S10661-008-0217-6
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“Chemical characterization and multivariate analysis of atmospheric PM2.5 particles”. Ravindra K, Stranger M, Van Grieken R, Journal of atmospheric chemistry 59, 199 (2008). http://doi.org/10.1007/S10874-008-9102-5
Abstract: The new European Council Directive (PE-CONS 3696/07) frames the inhalable (PM10) and fine particles (PM2.5) on priority to chemically characterize these fractions in order to understand their possible relation with health effects. Considering this, PM2.5 was collected during four different seasons to evaluate the relative abundance of bulk elements (Cl, S, Si, Al, Br, Cu, Fe, Ti, Ca, K, Pb, Zn, Ni, Mn, Cr and V) and water soluble ions (F−, Cl−, NO2 −, NO3 −, SO4 2−, Na+, NH4 +, Ca2+ and Mg2+) over Menen, a Belgian city near the French border. The air quality over Menen is influenced by industrialized regions on both sides of the border. The most abundant ionic species were NO3 −, SO4 2− and NH4 +, and they showed distinct seasonal variation. The elevated levels of NO3 − during spring and summer were found to be related to the larger availability of the NOx precursor. The various elemental species analyzed were distinguished into crustal and anthropogenic source categories. The dominating elements were S and Cl in the PM2.5 particles. The anthropogenic fraction (e.g. Zn, Pb, and Cu) shows a more scattered abundance. Furthermore, the ions and elemental data were also processed using principal component analysis and cluster analysis to identify their sources and chemistry. These approach identifies anthropogenic (traffic and industrial) emissions as a major source for fine particles. The variations in the natural/anthropogenic fractions of PM2.5 were also found to be a function of meteorological conditions as well as of long-range transport of air masses from the industrialized regions of the continent.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S10874-008-9102-5
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“EPXMA survey of shelf sediments (Southern Bight, North Sea): a glance beyond the XRD-invisible”. de Maeyer-Worobiec A, Dekov VM, Laane RWPM, Van Grieken R, Microchemical journal 91, 21 (2009). http://doi.org/10.1016/J.MICROC.2008.07.001
Abstract: Shelf sediments of the southern North Sea, were studied with a microanalytical [electron probe X-ray microanalysis (EPXMA)] and two bulk [X-ray diffraction (XRD) and X-ray fluorescence (XRF)] techniques. The investigation proved that the promptness of the microanalytical method is combined with a reasonable analytical reliability. XRD studies of such a type of sediments with monotonous mineral composition are not able to provide mineralogical information beyond the main well-crystalline minerals and the mineralogical quantitative characteristic of the sediment based on XRD estimations are incorrect. The EPXMA mineralogical interpretations are based on the statistical evaluation of a huge data set (thousands of mineral particles) and provide a rather correct quantitative determination of the main minerals. The comparative EPXMAXRF study revealed that the Al, Si, K, Ca, Fe and to some extent Ti contents estimated by EPXMA are fairly reliable. In this respect the accuracy of the EPXMA-based mineral identification of the pure silicates, pure aluminosilicates, and Al-, Ca-, Fe- and Ti-containing minerals with simple composition is very high. Mg-calcite, augite and apatite determinations are assessed to be correct. The supposed accuracy of the clay mineral determinations is slightly lower (7080%) than that of the other main minerals due to the complex and varying composition of the clays. The identification of XRD-invisible accessory minerals and quantification of their presence in the sediments is an essential advantage of the EPXMA, which makes it a useful approach in tracing the origin of the sediments, the pathways of their transport and the geochemical processes they have undergone. However, the EPXMA has several flaws, which need to be solved in the future sediment investigations: (1) calibration with natural standards is needed in order to provide a higher accuracy of the mineral determinations; (2) any EPXMA study of sediments needs to be secured with XRF examinations of selected samples since EPXMA gives only semi-quantitative information about the abundance of the elements; (3) ultra-thin window EPXMA of low-Z elements has to be used since some of them (O, C) are always present in the main sediment components: silicates, aluminosilicates, carbonates and metal oxyhydroxides; (4) the interpretations of the clay fraction have to be supported with detailed XRD investigations of selected samples, while the mineralogy of the silt and sand fractions needs to be backed up with optical microscopy studies. The information from different analytical techniques (EPXMA with XRFXRD-optical microscopy of selected samples) combined with the knowledge about the most possible minerals in a given environment, would give the most reliable results in studying mineralogical composition of shelf sediments.
Keywords: A1 Journal article; Laboratory Experimental Medicine and Pediatrics (LEMP); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.MICROC.2008.07.001
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“Sample damage during X-ray fluorescence analysis: case study on ammonium salts in atmospheric aerosols”. van Meel K, Worobiec A, Stranger M, Van Grieken R, Journal of environmental monitoring 10, 989 (2008). http://doi.org/10.1039/B807909A
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1039/B807909A
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“Inhable particulate matter from lime industries: chemical composition and deposition in human respiratory tract”. Godoi RHM, Braga DM, Makarovska Y, Alfoldy B, Carvalho Filho MAS, Van Grieken R, Godoi AFL, Atmospheric environment : an international journal 42, 7027 (2008). http://doi.org/10.1016/J.ATMOSENV.2008.07.002
Abstract: Air pollution caused by the lime production industry has become a serious problem with potential effects to human health, especially in developing countries. Colombo is a city included in the Metropolitan Region of Curitiba (capital of Parana State) in South Brazil. In Colombo city, a correlation has been shown between the lime production and the number of persons who need respiratory treatment in a local hospital, indicating that the lime industry can cause deleterious health effects in the exposed workers and population. This research was conducted to deal firstly with the characterization of the size distribution and chemical compositions of particles emitted from lime manufacturing and subsequently to assess the deposition rate of inhaled dolomitic lime aerosol particles in the human respiratory tract. The elemental chemical composition and particle size of individual atmospheric particles was quantitatively elucidated, including low-Z components like C, N and 0, as well as higher-Z elements, using automated electron probe microanalysis. Information concerning the bulk composition is provided by energy-dispersive X-ray detection. The majority of the respirable particulate matter identified was composed of aluminosilicates, Ca-Mg oxides, carbon-rich particles, mixtures of organic particles and Ca-Mg carbonates, soot and biogenic particles. In view of the chemical composition and size distribution of the aerosol particles, local deposition efficiencies in the human respiratory system were calculated, revealing the deposition of CaO center dot MgO at extrathoracic, tracheobronchial and pulmonary levels. The results of this study offer evidence to the threat of the fine and coarse particles emitted from dolomite lime manufacturing, allowing policy-makers to better focus their mitigation strategies in an effective way, as well as to the dolomite producers for the purpose of designing and/or implementing improved emission controls.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.ATMOSENV.2008.07.002
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“Modelling concentrations of airborne primary and secondary PM10 and PM2.5 with the BelEUROS-model in Belgium”. Deutsch F, Vankerkom J, Janssen L, Janssen S, Bencs L, Van Grieken R, Fierens F, Dumont G, Mensink C, Ecological modelling 217, 230 (2008). http://doi.org/10.1016/J.ECOLMODEL.2008.06.003
Abstract: The Eulerian Chemistry-Transport Model BelEUROS was used to calculate the concentrations of airborne PM10 and PM2.5 over Europe. Both primary as well as secondary particulate matter in the respirable size-range was taken into account. Especially PM2.5 aerosols are often formed in the atmosphere from gaseous precursor compounds. Comprehensive computer codes for the calculation of gas phase chemical reactions and thermodynamic equilibria between compounds in the gas-phase and the particulate phase had been implemented into the BelEUROS-model. Calculated concentrations of PM10 and PM2.5 are compared to observations, including both the spatial and daily, temporal distribution of particulate matter in Belgium for certain monitoring locations and periods. The concentrations of the secondary compounds ammonium, nitrate and sulfate have also been compared to observed values. BeIEUROS was found to reproduce the observed concentrations rather well. The model was applied to assess the contribution of emissions derived from the sector agriculture in Flanders, the northern part of Belgium, to PM10- and PM2.5-concentrations. The results demonstrate the importance of ammonia emissions in the formation of secondary particulate matter. Hence, future European emission abatement policy should consider more the role of ammonia in the formation of secondary particles
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.ECOLMODEL.2008.06.003
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“Elemental analysis of aerosols using proton-scattering”. Nelson JW, Williams I, Johansson TB, Van Grieken RE, IEEE transactions on nuclear science Ns21, 618 (1974). http://doi.org/10.1109/TNS.1974.4327522
Abstract: Elemental analysis for all of the light elements up through chlorine by elastic scattering of 16 MeV protons has been shown to be feasible. Basic problems associated with such measurements are discussed including kinematics, angular distribution, and sample backings. Spectra are presented for air particulate matter for both a total filter (Nuclepore) and a size fractionated air impactor (polystyrene backed) sample. The method is absolute, non destructive and can be used in conjunction with proton induced x-ray fluorescence to quantitatively analyze all elements in the same sample in minutes of time.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1109/TNS.1974.4327522
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“Associations between PM2.5 and heart rate variability are modified by particle composition and beta-blocker use in patients with coronary heart disease”. de Hartog JJ, Lanki T, Timonen KL, Hoek G, Janssen NAH, Ibald-Mulli A, Peters A, Heinrich J, Tarkainen TH, Van Grieken R, van Wijnen JH, Brunekreef B, Pekkanen J, Environmental health perspectives 117, 105 (2009). http://doi.org/10.1289/EHP.11062
Abstract: Background: It has been hypothesized that ambient particulate air pollution is able to modify the autonomic nervous control of the heart, measured as heart rate variability (HRV) . Previously we reported heterogeneous associations between particulate matter with aerodynamic diameter < 2.5 µm (PM2.5) and HRV across three study centers. Objective: We evaluated whether exposure misclassification, effect modification by medication, or differences in particle composition could explain the inconsistencies. Methods: Subjects with coronary heart disease visited clinics biweekly in Amsterdam, the Netherlands ; Erfurt, Germany ; and Helsinki, Finland for 68 months. The standard deviation (SD) of NN intervals on an electrocardiogram (ECG ; SDNN) and high frequency (HF) power of HRV was measured with ambulatory ECG during paced breathing. Outdoor levels of PM2.5 were measured at a central site. In Amsterdam and Helsinki, indoor and personal PM2.5 were measured during the 24 hr preceding the clinic visit. PM2.5 was apportioned between sources using principal component analyses. We analyzed associations of indoor/personal PM2.5, elements of PM2.5, and source-specific PM2.5 with HRV using linear regression. Results: Indoor and personal PM2.5 were not associated with HRV. Increased outdoor PM2.5 was associated with decreased SDNN and HF at lags of 2 and 3 days only among persons not using beta-blocker medication. Traffic-related PM2.5 was associated with decreased SDNN, and long-range transported PM2.5 with decreased SDNN and HF, most strongly among persons not using beta blockers. Indicators for PM2.5 from traffic and long-range transport were also associated with decreased HRV. Conclusions: Our results suggest that differences in the composition of particles, beta-blocker use, and obesity of study subjects may explain some inconsistencies among previous studies on HRV.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1289/EHP.11062
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“Aqueous solubility calculation for petroleum mixtures in soil using comprehensive two-dimensional gas chromatography analysis data”. Mao D, Lookman R, van de Weghe H, Vanermen G, de Brucker N, Diels L, Journal of chromatography : A 1216, 2873 (2009). http://doi.org/10.1016/J.CHROMA.2008.08.072
Abstract: An assessment of aqueous solubility (leaching potential) of soil contaminations with petroleum hydrocarbons (TPH) is important in the context of the evaluation of (migration) risks and soil/groundwater remediation. Field measurements using monitoring wells often overestimate real TPH concentrations in case of presence of pure oil in the screened interval of the well. This paper presents a method to calculate TPH equilibrium concentrations in groundwater using soil analysis by high-performance liquid chromatography followed by comprehensive two-dimensional gas chromatography (HPLCGCXGC). The oil in the soil sample is divided into 79 defined hydrocarbon fractions on two GCXGC color plots. To each of these fractions a representative water solubility is assigned. Overall equilibrium water solubility of the non-aqueous phase liquid (NAPL) present in the sample and the water phase's chemical composition (in terms of the 79 fractions defined) are then calculated using Raoult's law. The calculation method was validated using soil spiked with 13 different TPH mixtures and 1 field-contaminated soil. Measured water solubilities using a column recirculation equilibration experiment agreed well to calculated equilibrium concentrations and water phase TPH composition.
Keywords: A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
DOI: 10.1016/J.CHROMA.2008.08.072
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“Morphology and the chemical make-up of the inorganic components of black corals”. Nowak D, Florek M, Nowak J, Kwiatek W, Lekki J, Chevallier P, Hacura A, Wrzalik R, Ben-Nissan B, Van Grieken R, Kuczumow A, Materials science and engineering: part C: biomimetic materials 29, 1029 (2009). http://doi.org/10.1016/J.MSEC.2008.08.028
Abstract: Black corals (Cnidaria, Antipatharia) from three different sources were investigated with the aim of detecting inorganic components and their morphology. In general, the skeleton of black corals was composed of the chitin fibrils admixed with peptides and the chitin presence was confirmed by the X-ray diffraction (XRD), Fourier Transformed Infrared Spectrometry (FTIR) and microRaman Microscopy, the latter giving the opportunity of tracing single fibrils and their location. The composition and concentrations of the inorganic components of the black corals were measured, using a scanning electron microprobe and micro-Particle Induced X-ray Emission (µ-PIXE). The application of such instruments enabled the estimation of the constituent distributions in a microscale. The mapping option was the most useful technique of making analyses in these studies, just to reveal the composition of chamber-like cells. Analysis of the morphology and microstructure showed that there were three distinct regions within the coral: a core and the cells encircled with adjacent interface gluing strips. The majority of the elements analyzed were selectively distributed and segregated in a striking way in mentioned distinctive zones of the skeleton and it was detected for the first time. The core area was characterized by the relatively elevated concentrations of Ca. The measurements gave extremely clear images of the distribution of particular elements in the skeletal tissue, with I, Ca, K and Fe much more concentrated in the gluing zones, while C, N, Na and Mg present in the interiors of particular skeletal cells. The distribution of some elements (Mg, Fe) and some compounds (chitin) and functional groups (SS, CI) allows differentiating the biological and mechanical functions of particular fragments of the rods. The kinds of elements and their concentrations measured were essentially in compliance with rare data available in the literature. The Raman technique gave the additional qualitative information about the structure of gluing zone and the chitin fibrils and surrounding matrix inside the cell interior.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.MSEC.2008.08.028
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“Recognition of uranium oxides in soil particulate matter by means of ì-Raman spectrometry”. Stefaniak EA, Sajó, I, Alsecz A, Worobiec A, Máthé, Z, Török S, Van Grieken R, Journal of nuclear materials 381, 278 (2008). http://doi.org/10.1016/J.JNUCMAT.2008.08.036
Abstract: Soil samples from an abandoned uranium mine have been investigated in order to determine the molecular phases of uranium compounds. The experiments were carried out with soil particulate matter, collected randomly from the area of the formerly exploited ore. To select the particles rich with uranium, scanning electron microscopy with energy-dispersive X-ray attachment (SEM/EDX) was applied first. Afterwards, the particles were relocated and measured by l-Raman spectrometry (MRS). Residues of the main deposit, uraninite UO2, were detected, along with its alteration products. In terms of Raman scattering properties, uranium oxides are quite sensitive to the laser beam wavelength, which results in very specific features of their Raman spectra. In this paper the Raman spectra of uranium oxides of different origin and oxidation states, measured with 514 and 785 nm lasers, are also presented
Keywords: A1 Journal article; Laboratory Experimental Medicine and Pediatrics (LEMP); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.JNUCMAT.2008.08.036
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“Characterization of indoor air quality in primary schools in Antwerp, Belgium”. Stranger M, Potgieter-Vermaak SS, Van Grieken R, Indoor air: international journal of indoor quality and climate 18, 454 (2008). http://doi.org/10.1111/J.1600-0668.2008.00545.X
Abstract: The indoor air quality of 27 primary schools located in the city centre and suburbs of Antwerp, Belgium, was assessed. The primary aim was to obtain correlations between the various pollutant levels. Indoor:outdoor ratios and the building and classroom characteristics of each school were investigated. This paper presents results on indoor and local outdoor PM2.5 mass concentrations, its elemental composition in terms of K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Pb, Al, Si, S, and Cl, and its black smoke content. In addition, indoor and local outdoor levels of the gases NO2, SO2, O3, and BTEX (benzene, toluene, ethyl benzene, and xylene isomers) were determined. Black smoke, NO2, SO2 and O3, occurred at indoor:outdoor ratios below unity, indicating their significant outdoor sources. No linear correlation was established between indoor and outdoor levels for PM2.5 mass concentrations and BTEX; their indoor:outdoor ratios exceeded unity except for benzene. Classroom PM2.5 occurred with a different elemental composition than local outdoor PM2.5. The re-suspension of dust because of room occupation is probably the main contributor for the I/O ratios higher than 1 reported for elements typically constituting dust particles. Finally, increased benzene concentrations were reported for classrooms located at the lower levels.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1111/J.1600-0668.2008.00545.X
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“Resolving the unresolved complex mixture in motor oils using high-performance liquid chromatography followed by comprehensive two-dimensional gas chromatography”. Mao D, van de Weghe H, Lookman R, Vanermen G, de Brucker N, Diels L, Fuel 88, 312 (2009). http://doi.org/10.1016/J.FUEL.2008.08.021
Abstract: High-performance liquid chromatography (HPLC) followed by comprehensive two-dimensional gas chromatography (GC×GC) was used for detailed group-type characterization of hydrocarbons present in motor oils. With conventional GC, motor oil is not well separated due to its complexity, resulting in a hump in the chromatogram: the unresolved complex mixture (UCM). With HPLC-GC×GC, motor oil hydrocarbons can be quantitatively separated into four major groups: alkanes, cycloalkanes, alkenes and aromatics. Each group can be further separated and divided by ring number or carbon number. Three selected motor oil samples were characterized by HPLC-GC×GC including two conventional motor oils and a synthetic motor oil. Using a proprietary silver-modified HPLC column, the aromatic components in motor oils were baseline separated from the aliphatic UCM and were then further separated by GC×GC based on their aromatic ring numbers. Accordingly, the aliphatic components were separated by GC×GC based on their saturated ring numbers. This paper illustrates the capabilities of HPLC-GC×GC for reliable and detailed quantitative group-type characterization of hydrocarbons present in motor oils.
Keywords: A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
DOI: 10.1016/J.FUEL.2008.08.021
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“Comparative assessment of air quality in two health resorts using carbon isotopes and palynological analyses”. Górka M, Jedrysek MO, Maj J, Worobiec A, Buczyńska A, Stefaniak E, Krata A, Van Grieken R, Zwozdziak A, Sówka I, Zwozdziak J, Lewicka-Szczebak D, Atmospheric environment 43, 682 (2009). http://doi.org/10.1016/J.ATMOSENV.2008.09.056
Abstract: This paper describes results of applying the palynological and carbon isotopic analysis of the organic fraction of Total Suspended Particles (TSP) to discriminate distinct pollution sources and assess the anthropogenic impact for the investigated areas. The samples of atmospheric particles were collected in Czerniawa and Cieplice (two health resorts in Lower Silesia, SW Poland) twice a year in summer and winter season (from July 2006 to February 2008). The palynological spectra represent in the vast majority local plant communities without a noticeable contribution of long-transported plant particles. Palynological analysis revealed also differences in the specificity of the two sampling areas, i.e. the higher contribution of identified organic material in Czerniawa stands for more natural character of this site, but is also responsible for the higher allergic pressure when compared to Cieplice. The carbon isotopic composition of TSP varied seasonally (ä13C value from −27.09 in summer to −25.47 in winter). The increased ä13C value in winter (heating period) is most probably caused by uncontrolled contribution of coal soot. On the basis of isotopic mass balance the calculated contribution of anthropogenic organic particles in the atmosphere reached in winter season 72% in Czerniawa and 79% in Cieplice.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1016/J.ATMOSENV.2008.09.056
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“Atmospheric BTEX-concentrations in an area with intensive street traffic”. Buczyńska AJ, Krata A, Stranger M, Godoi AFL, Kontozova-Deutsch V, Bencs L, Naveau I, Roekens E, Van Grieken R, Atmospheric environment : an international journal 43, 311 (2009). http://doi.org/10.1016/J.ATMOSENV.2008.09.071
Abstract: The major threat to clean air in developed and industrializing countries is now posed by traffic emissions. The effects of traffic road modifications on the air quality are, however, rarely reported in the literature. The aim of this study was to determine the influence of the modernization and renovation of a traffic artery in the region of Mortsel (Antwerp, Belgium) on the concentration of volatile organic compounds such as: benzene, toluene, ethylbenzene and m-, p-, o-xylenes (BTEX). The original goal of the reconstruction works was to reduce the traffic lanes of one of the busiest streets in Antwerp, in order to discourage the road traffic and in consequence also to improve the air quality in this region. The average concentrations of BTEX before these works in 2003 were: 1.6, 7.0, 0.9, 2.3, and 0.9 ìg/m3, for benzene, toluene, ethylbenzene, m + p xylenes, and o-xylene, respectively. However, after the completion of the works, in 2005, they were slightly higher: 2.5, 9.5, 1.6, 3.4, and 1.3 ìg/m3, respectively. The scatter plots of benzene against toluene, ethylbenzene and xylenes in 2003 and 2005 showed very good correlations. This fact indicated that all of the measured compounds originated from the same source, namely the road traffic. Moreover, the data obtained from an air-monitoring station at less than 6 km distance from the sampling site (operated by the Flemish Environment Agency, and located in Borgerhout, Antwerp), confirmed the lack of influence of background concentrations of BTEX. The obtained results led to the conclusion that the reduction of the number of traffic lanes had apparently increased the traffic jams and also increased the emission from cars. Therefore, these modernization works had even a negative impact on the local concentration of traffic-related pollutants as BTEX.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.ATMOSENV.2008.09.071
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“Editorial: Award for best XRS referee during 2007-2008”. Van Grieken R, X-ray spectrometry 37, 571 (2008). http://doi.org/10.1002/XRS.1107
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1002/XRS.1107
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“Mass and ionic composition of atmospheric fine particles over Belgium and their relation with gaseous air pollutants”. Bencs L, Ravindra K, de Hoog J, Rasoazanany EO, Deutsch F, Bleux N, Berghmans P, Roekens E, Krata A, Van Grieken R, Journal of environmental monitoring 10, 1148 (2008). http://doi.org/10.1039/B805157G
Abstract: Mass, major ionic components (MICs) of PM2.5, and related gaseous pollutants (SO2, NOx, NH3, HNO2, and HNO3) were monitored over six locations of different anthropogenic influence (industrial, urban, suburban, and rural) in Belgium. SO42-, NO3-, NH4+, and Na+ were the primary ions of PM2.5 with averages diurnal concentrations ranging from 0.44.5, 0.37.6, 0.94.9, and 0.41.2 µg m-3, respectively. MICs formed 39% of PM2.5 on an average, but it could reach up to 8098%. The SO2, NO, NO2, HNO2, and HNO3 levels showed high seasonal and site-specific fluctuations. The NH3 levels were similar over all the sites (26 µg m-3), indicating its relation to the evenly distributed animal husbandry activities. The sulfur and nitrogen oxidation ratios for PM2.5 point towards a low-to-moderate formation of secondary sulfate and nitrate aerosols over five cities/towns, but their fairly intensive formation over the rural Wingene. Cluster analysis revealed the association of three groups of compounds in PM2.5: (i) NH4NO3, KNO3; (ii) Na2SO4; and (iii) MgCl2, CaCl2, MgF2, CaF2, corresponding to anthropogenic, sea-salt, and mixed (sea-salt + anthropogenic) aerosols, respectively. The neutralization and cation-to-anion ratios indicate that MICs of PM2.5 appeared mostly as (NH4)2SO4 and NH4NO3 salts. Sea-salt input was maximal during winter reaching up to 12% of PM2.5. The overall average Cl-loss for sea-salt particles of PM2.5 at the six sites varied between 69 and 96% with an average of 87%. Principal component analysis revealed vehicular emission, coal/wood burning and animal farming as the dominating sources for the ionic components of PM2.5.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1039/B805157G
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“Tracing the metal pollution history of the Tisza River through the analysis of a sediment depth profile”. Nguyen HL, Braun M, Szaloki I, Baeyens W, Van Grieken R, Leermakers M, Water, air and soil pollution 200, 119 (2009). http://doi.org/10.1007/S11270-008-9898-2
Abstract: The vertical profiles of 20 major and trace metals were investigated along a 180-cm-long sediment core, which was sampled at Kiss-Janosne-Holt Tisza, an oxbow lake located in the upper part of the Tisza River in Hungary. The vertical profiles showed sharp peaks at different depths, reflecting historical pollution events and unusual changes of river water characteristics. Five different groups of metals, containing metals which were strongly correlated and showing a similar behaviour, could be distinguished by factor analysis. Six areas, with variable degrees and types of contamination, were classified in the sediment core with cluster analysis. The most polluted sections were found in the upper 50-cm part (significantly contaminated by Cu, Zn, Pb, Cd and Hg) and the deeper 100120-cm part (characterised by high concentrations of metals associated with mining activities, such as Fe and Mn, as well as Cu, Zn and Pb). In recent years, important pollution events, such as the one which took place in March of 2000, were the reason for pollution of the upper sediment layers, whereas mining activities during the last century were responsible for the pollution of the deeper core sections.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S11270-008-9898-2
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“Particulate matter and gaseous pollutants in residences in Antwerp, Belgium”. Stranger M, Potgieter-Vermaak SS, Van Grieken R, The science of the total environment 407, 1182 (2009). http://doi.org/10.1016/J.SCITOTENV.2008.10.019
Abstract: This comprehensive study, a first in Flanders, Belgium, aimed at characterizing the residential indoor air quality of subgroups that took part in the European Community Respiratory Health Survey (ECRHS I1991 and ECHRS II1996) questionnaire-based asthma and related illnesses studies. This pilot study aimed at the evaluation of particulate matter and various inorganic gaseous compounds in residences in Antwerp. In addition personal exposure to the gaseous compounds of one individual per residence was assessed. The main objective was to obtain some base-line pollutant levels and compare these with studies performed in other cities, to estimate the indoor air quality in residences in Antwerp. Correlations between the various pollutant levels, indoor:outdoor ratios and the micro-environments of each residence were investigated. This paper presents results on indoor and ambient PM1, PM2.5 and PM10 mass concentrations, its elemental composition in terms of K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Pb, Al, Si, S and Cl and the water-soluble ionic concentrations in terms of SO42−, NO32−, Cl−, NH4+ K+, Ca2+. In addition, indoor, ambient and personal exposure levels of the gases NO2, SO2, and O3 were determined. Elevated indoor:outdoor ratios were found for NO2 in residences containing gas stoves. In smoker's houses increased PM concentrations of 58 and 43% were found for the fine and coarse fractions respectively. Contrary to the fact that all I/O ratios of the registered elements in each individual house were significantly correlated to each other, no correlation could be established between the I/O ratios of the different houses, thus indicating a unique micro-environment for each residence. Linear relationships between the particulate matter elemental composition, SO2 and O3 levels indoors and outdoors could be established. No linear relationships between indoor and outdoor NO2 and particulate mass concentrations were found.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.SCITOTENV.2008.10.019
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“Determination of selenium in blood components by X-ray emission spectrometry”. Robberecht H, Deelstra H, Van Grieken R, Biological trace element research 25, 149 (1990). http://doi.org/10.1007/BF02990412
Abstract: Sampling, storing, sample pretreatment, and experimental conditions for selenium (Se) determination in human serum, plasma, and whole blood by X-ray emission spectrometric (XRS) methods are described. Concentration levels in these biological fluids, found by this technique, are discussed and compared to values found by other techniques for the same healthy population group in the same area. XRS analysis of blood from patients with various pathological conditions is reviewed, with special attention to the relation of Se with the concentration level of other essential or nonessential trace elements.
Keywords: A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/BF02990412
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“Variation of K X-ray fluorescence cross-sections of Cu, Y and Ba in YBa2Cu3O7-\delta superconductor”. Baltas H, Čevik U, Solid state communications 149, 231 (2009). http://doi.org/10.1016/J.SSC.2008.11.010
Abstract: K X-ray fluorescence cross-sections of Cu, Y and Ba elements were measured in CuO, Y(2)O(3), BaCO(3) Compounds and YBa(2)Cu(3)O(7-delta) superconductor samples (nonreacted agent, calcined and sintered states). A superconductor sample of YBa(2)Cu(3)O(7-delta) was prepared by using a solid-state reaction technique. The samples were excited by gamma rays of energy 59.5 keV from a (241)Am radioisotope source. The Cu, Y and Ba K X-ray intensities counted with a Si(Li) detector were measured in different solid-state conditions. The obtained values of K X-ray fluorescence cross-section were compared with the theoretical values of pure Cu, Y and Ba elements. We found that the K X-ray fluorescence cross-section of Cu, Y and Ba in YBa(2)Cu(3)O(7-delta) sample is changed in different solid-state conditions, depending on the mixture (nonreacted agent), calcined and sintered states. (c) 2008 Elsevier Ltd. All rights reserved.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.SSC.2008.11.010
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“Exposure assessment of a cyclist to PM10 and ultrafine particles”. Berghmans P, Bleux N, Int Panis L, Mishra VK, Torfs R, Van Poppel M, The science of the total environment 407, 1286 (2009). http://doi.org/10.1016/J.SCITOTENV.2008.10.041
Abstract: Estimating personal exposure to air pollution is a crucial component in identifying high-risk populations and situations. It will enable policy makers to determine efficient control strategies. Cycling is again becoming a favorite mode of transport both in developing and in developed countries due to increasing traffic congestion and environmental concerns. in Europe, it is also seen as a healthy sports activity. However, due to high levels of hazardous pollutants in the present day road microenvironment the cyclist might be at a higher health risk due to higher breathing rate and proximity to the vehicular exhaust. In this paper we present estimates of the exposure of a cyclist to particles of various size fractions including ultrafine particles (UFP) in the town of Mol (Flanders, Belgium). The results indicate relatively higher UFP concentration exposure during morning office hours and moderate UFP levels during afternoon. The major sources of UFP and PM(10) were identified, which are vehicular emission and construction activities, respectively. We also present a dust mapping technique which can be a useful tool for town planners and local policy makers. (C) 2008 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
DOI: 10.1016/J.SCITOTENV.2008.10.041
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