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101. Lead isotopic compositions in the EPICA Dome C ice core and Southern Hemisphere Potential Source Areas

Author

Vallelonga, Paul, Gabrielli, P., Balliana, E., Wegner, A., Delmonte, B., Turetta, C., Burton, G., Vanhaecke, F., Rosman, K.J.R., Hong, S., Boutron, C.F., Cescon, P., Barbante, C., Vallelonga, Paul, Gabrielli, P., Balliana, E., Wegner, A., Delmonte, B., Turetta, C., Burton, G., Vanhaecke, F., Rosman, K.J.R., Hong, S., Boutron, C.F., Cescon, P., and Barbante, C.

Abstract

A record of Pb isotopic compositions and Pb and Ba concentrations are presented for the EPICA Dome C ice core covering the past 220 ky, indicating the characteristics of dust and volcanic Pb deposition in central East Antarctica. Lead isotopic compositions are also reported in a suite of soil and loess samples from the Southern Hemisphere (Australia, Southern Africa, Southern South America, New Zealand, Antarctica) in order to evaluate the provenance of dust present in Antarctic ice. Lead isotopic compositions in Dome C ice support the contention that Southern South America was an important source of dust in Antarctica during the last two glacial maxima, and furthermore suggest occasional dust contributions from local Antarctic sources. The isotopic signature of Pb in Antarctic ice is altered by the presence of volcanic Pb, inhibiting the evaluation of glacial–interglacial changes in dust sources and the evaluation of Australia as a source of dust to Antarctica. Consequently, an accurate evaluation of the predominant source(s) of Antarctic dust can only be obtained from glacial maxima, when dust-Pb concentrations were greatest. These data confirm that volcanic Pb is present throughout Antarctica and is emitted in a physical phase that is free from Ba, while dust Pb is transported within a matrix containing Ba and other crustal elements.

Published
2010

102. Lead isotopic compositions in the EPICA Dome C ice core and Southern Hemisphere Potential Source Areas

Author

Vallelonga, P, Gabrielli, P, Balliana, E, Wegner, A, Delmonte, B, Turetta, C, Burton, G, Vanhaecke, F, Rosman, K, Hong, S, Boutron, C, Cescon, P, Barbante, C, Rosman, KJR, Boutron, CF, Barbante, C., DELMONTE, BARBARA, Vallelonga, P, Gabrielli, P, Balliana, E, Wegner, A, Delmonte, B, Turetta, C, Burton, G, Vanhaecke, F, Rosman, K, Hong, S, Boutron, C, Cescon, P, Barbante, C, Rosman, KJR, Boutron, CF, Barbante, C., and DELMONTE, BARBARA

Published
2009

104. Urinary uranium and kidney function parameters in professional assistance workers in the Epidemiological Study Air Disaster in Amsterdam (ESADA)

Author

Bijlsma, J.A., Slottje, P., Huizink, A.C., Twisk, J.W.R., Voet, G.B. van der, Wolff, F.A. de, Vanhaecke, F., Moens, L., Smid, T., Bijlsma, J.A., Slottje, P., Huizink, A.C., Twisk, J.W.R., Voet, G.B. van der, Wolff, F.A. de, Vanhaecke, F., Moens, L., and Smid, T.

Abstract

Item does not contain fulltext, Background. The Epidemiological Study Air Disaster in Amsterdam (ESADA) aimed to assess long-term health effects in professional assistance workers involved in the 1992 air disaster in Amsterdam. As part of ESADA indications of nephrotoxicity due to exposure to uranium from the balance weights of the crashed aircraft were assessed. Methods. Data of a historically defined cohort of 2499 (exposed and non-exposed) firefighters, police officers and hangar workers were collected 8.5 years after the disaster. Urinary uranium concentrations were determined by sector field inductively coupled plasma mass spectrometry. Urine albumincreatinine ratio and fractional excretion of beta(2)-microglobulin were calculated from a single-spot urine specimen and simultaneous blood sample. Exposed assistance workers were compared with their non-exposed colleagues, and associations between uranium and kidney function parameters were explored. Results. Median uranium concentrations were around 2 ng/g creatinine. Median values of albumincreatinine ratio and fractional excretion of beta(2)-microglobulin were well below the level for microalbuminuria and for tubular damage, respectively. No statistically significant differences between exposed and non-exposed workers were found in uranium concentrations and kidney function parameters, although exposed hangar workers had lower uranium concentrations. No statistically significant associations were found between uranium concentrations and kidney function parameters in the total cohort. Conclusions. Occupational exposure to the air disaster in Amsterdam was neither significantly associated with higher uranium concentrations, nor with disturbed kidney function parameters. In this large cohort of professional assistance workers, urinary uranium concentrations were in the low range compared with previously published reference populations. No indications of nephrotoxicity were found at urinary uranium concentrations around 2 ng/g creatinine.

Published
2008

106. A synthesis of diamond and inclusion trace element studies

Author

UCL - FSA/INMA - Département d'ingénierie mathématique, Tomlinson, E, De Schrijver, I, De Corte, K, Vanhaecke, F, Moens, Luc, 15th Annual V M Goldschmidt Conference, UCL - FSA/INMA - Département d'ingénierie mathématique, Tomlinson, E, De Schrijver, I, De Corte, K, Vanhaecke, F, Moens, Luc, and 15th Annual V M Goldschmidt Conference

Published
2005

113. Waterborne versus Dietary Zinc Accumulation and Toxicity in Daphnia magna: a Synchrotron Radiation Based X-ray Fluorescence Imaging Approach

Author

Evens, R., primary, De Schamphelaere, K. A. C., additional, De Samber, B., additional, Silversmit, G., additional, Schoonjans, T., additional, Vekemans, B., additional, Balcaen, L., additional, Vanhaecke, F., additional, Szaloki, I., additional, Rickers, K., additional, Falkenberg, G., additional, Vincze, L., additional, and Janssen, C. R., additional

Published
2011
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122. F-59 X-ray Imaging on Biological Model Organisms Using Micro and Nano X-ray Fluorescence

Author

De Samber, B., primary, De Schamphelaere, K., additional, Masschaele, B., additional, Vanblaere, S., additional, Vanhaecke, F., additional, Van Hoorebeke, L., additional, Janssen, C., additional, Vincze, L., additional, Bohic, S., additional, Martinez-Criado, G., additional, Tuculou, R., additional, Cloetens, P., additional, and Falkenberg, G., additional

Published
2009
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129. A combination of synchrotron and laboratory X-ray techniques for studying tissue-specific trace level metal distributions in Daphnia magna

Author

De Samber, B., primary, Evens, R., additional, De Schamphelaere, K., additional, Silversmit, G., additional, Masschaele, B., additional, Schoonjans, T., additional, Vekemans, B., additional, Janssen, C. R., additional, Van Hoorebeke, L., additional, Szalóki, I., additional, Vanhaecke, F., additional, Falkenberg, G., additional, and Vincze, L., additional

Published
2008
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133. A simple dilute-and-shoot approach for the determination of ultra-trace levels of arsenic in biological fluids via ICP-MS using CH3F/He as a reaction gas.

Author

Flórez, M. R., García-Ruiz, E., Bolea-Fernández, E., Vanhaecke, F., and Resano, M.

Subjects
FLUIDS, FLUID mechanics, ARSENIC, NATIVE element minerals, CACODYLIC acid
Abstract

The performance of a mixture of CH3F/He (1/9) as a reaction gas for the determination of As in biological fluids using a quadrupole ICP-MS instrument has been explored. A simple (dilute-and-shoot) interference-free method has been developed to quantify As concentrations at trace and ultra-trace levels in matrices with a high Cl content. As+ reacts with CH3F (through CH3F addition, followed by HF elimination) with high efficiency forming AsCH2+ as the primary reaction product, which can be monitored at a mass-to-charge ratio of 89, free from the Cl-based interferents (e.g., 40Ar35Cl+ and 40Ca35Cl+) that hamper the monitoring of 75As+. Matrix effects are overcome by the use of Te as an internal standard and the addition of 3% v/v ethanol to all samples and calibration standard solutions. The method presented was validated by analysing a set of reference materials (blood, serum and urine) and by assessing As recovery from a set of real blood samples. With this method, the limit of detection was calculated to be 0.8 ng L−1 As, favourably comparable to the vast majority of values reported in the literature, even with those obtained using more sophisticated sector-field instrumentation. [ABSTRACT FROM AUTHOR]

Published
2016
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150. THE EFFECTS OF THERMAL PROCESSING ON THE BUDGET OF LITHOPHILE ELEMENTS IN H CHONDRITES.

Author

Maeda, R., Goderis, S., Van Acker, T., Vanhaecke, F., Yamaguchi, A., Debaille, V., and Claeys, P.

Subjects
LASER ablation inductively coupled plasma mass spectrometry, RARE earth metals, TRACE elements, CHONDRITES, BUDGET process, PLAGIOCLASE, FLUORESCENCE spectroscopy
Abstract

Introduction: Elements are fractionated between the constituent minerals in meteorites, mainly depending on their ionic radii and partition coefficients. Previous studies have described these elemental distributions among the constituent minerals using physical mineral separation, chemical leaching techniques, or in-situ analyses [e.g., 1, 2], significantly improving our understanding of the conditions of equilibration induced by thermal metamorphism on their parent bodies, variations of isotopic compositions, etc. [e.g., 3]. In addition, it has been demonstrated that some elements are re-distributed into (a) specific mineral(s) during thermal metamorphism on their parent bodies. For example, rare earth elements (REEs) except for Eu are mostly present in Ca-phosphates in the case of equilibrated ordinary chondrites while these elements are partitioned in glass mesostasis in chondrules for unequilibrated ordinary chondrites [4]. Nevertheless, the budgets of other lithophile elements and the thermal effects on their distribution remain poorly understood. Here, we address the lithophile element budgets of both unequilibrated and equilibrated H chondrites (HCs). Samples and Methods: Polished thick sections (PTSs) were prepared for ten Antarctic HCs, two HCs collected from hot deserts, and four fall HCs, with the petrologic types varying from 3.3 to 7. All samples were provided by the Royal Belgian Institute of Natural Sciences (RBINS), Belgium, and the National Institue of Polar Research (NIPR), Japan. Firstly, these PTSs were analyzed using micro-X-ray fluorescence spectrometry (µXRF) at the Vrije Universiteit Brussel (VUB), Belgium, to obtain maps showing the distribution of the major elements. Secondly, back-scattered electron (BSE) images of all samples were acquired using a field emission-scanning electron microscope (FE-SEM) equipped with an energy-dispersive spectrometer (EDS) at NIPR. Once the constituent minerals in the samples were identified based on the elemental maps and BSE images obtained, an electron probe micro analyzer (EPMA) at NIPR was used for the determination of the major element abundances in each constituent mineral. After EPMA analysis, semi-quantitative trace element mapping was conducted for selected samples using laser ablation-inductively coupled plasma-time of flight-mass spectrometry (LA-ICP-TOF-MS) at Ghent University, Belgium. Finally, the abundances of lithophile elements were determined for Ca-phosphates and silicates using a LA system coupled to a sector field ICP-MS in single-point drilling mode at NIPR. Combined with their bulk elemental abundances previously determined at the Université libre de Bruxelles (ULB), Belgium, or relying on literature data [5, 6], mass balances were calculated for all samples. Results and Discussion: For the most unequilibrated sample in this study, A-880941 (H3.3), only ~50-70% of the bulk REE abundance except for Eu is hosted in the main mineral phases analyzed, despite the fairly good agreement with the bulk major element composition. In addition, the Ca-phosphate phase in A-880941 accommodates ~25-40% of the REE content. On the other hand, the estimated whole-rock REE abundances in equilibrated samples are in excellent agreement with their bulk abundances, and ~60-90% of the REE content is allocated in Caphosphates. These observations are entirely consistent with the redistribution scenario of REEs during thermal metamorphism, as described by Shinotsuka and Ebihara [4]. In a similar manner, some high field strength elements such as Hf appear to originally have been distributed in chondrule glasses and then in feldspar (e.g., ~40-60% of Hf in plagioclase for unequilibrated HCs) based on both this study and Alexander [7]. As ~60-80% and less than 15% of Hf are allocated in Ca-rich pyroxene and plagioclase for equilibrated HCs, respectively, it appears that Hf is redistributed from plagioclase into Ca-rich pyroxene with the growth of Ca-rich pyroxene and plagioclase during thermal metamorphism. We observe that a considerable amount of specific trace elements (e.g., REEs, Th, and U) reside in cracks formed during terrestrial alteration [8], hence their deposition in cracks may need to be taken into account during mass balance considerations to explain the discrepancies observed between the estimated whole-rock abundances and the bulk abundances. [ABSTRACT FROM AUTHOR]

Published
2022

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