Search results for "Trace"

Trace elements and plasma metabolomics in a general population from Spain: The Hortega Study

2021

Development of accurate mass spectrometric routine and reference methods for the determination of trace amounts of iridium and rhodium in photographi…

1999

For the determination of trace amounts of iridium and rhodium in photographic emulsions different sample treatment procedures were coupled with inductively coupled plasma mass spectrometry (ICP-MS) and, for iridium, also with negative thermal ionisation isotope dilution mass spectrometry (NTI-IDMS) and ICP-IDMS. IDMS determinations of iridium were carried out using an enriched 191Ir spike solution. Elimination of the silver matrix was established for both mass spectrometric methods, which prevents corresponding memory effects in the ICP-MS system and is essential for the formation of IrO2 - thermal ions, respectively. For NTI-MS measurements, the gelatine matrix of the emulsion must also be…

Exposure to trace elements by hair mineral analysis. Mining , volcanic and urban areas

2015

Concerns about the effects of environmental exposure to metals and metalloids on human health have driven the scientific community to find reliable tools and methodologies for assessing the impact of emission of toxic metals from anthropogenic sources or through natural anomalous levels of metals in water, soil and air. Biological monitoring has been extensively employed with this end in view and blood, urine, hair and nails are the biological materials mostly collected and analyzed for the levels of multiple metals. With respect to blood and urine, whose metal concentrations decrease rapidly after the exposure period, hair and nails appear to be of greater value in evaluating past and cont…

Trace-element partitioning between amphibole and silicate melt.

2007

Knowledge of the partitioning behavior of trace elements between solid and liquid is a prerequisite for modern igneous and mantle petrology. Most of the mathematical models simulating melt generation, migration and evolution within the mantle and/or the crust require the availability of reliable solid/liquid partition coefficients for the mineral phases involved in the process. Calcic amphiboles are extremely important for the understanding of lithospheric processes because of both their common occurrence in a variety of igneous and metamorphic rocks types and their capability of hosting a large number of geochemically important trace elements. A series of studies on the partitioning behavi…

Metals in Scalp Hair from Relapsing-Remitting Multiple Sclerosis Patients (RRMS)

2014

We measured the concentrations of 21 chemical elements (TE) in hair of 48 Sicilian patients with RRMS compared with 51 controls (HC). MS patients showed a significantly (p<0.01) lower hair concentration of Al and Rb and higher hair concentration of U compared to HC. The percentage of MS patients showing hair elemental concentrations greater than the 95th percentile of controls was 20% for Ni, 19% for Ba and U, and 15% for Ag, Mo and Se. The ratio Zn/Cu varied from 17 to 19, with no significant differences between HC and MS groups or between individuals differentiated by gender. No significant association was found between levels of each TE and age, disease duration, Expanded Disability Stat…

Trace elemental composition of PM2.5 atmospheric aereosol in Palermo urban area

2009

Trace element behavior in the fluidized bed gasification of solid recovered fuels

2013

Gasification of biomass and recycled fuels is of particular interest for the efficient production of power and heat. Trace elements present as impurities in the product gas should be removed very efficiently. The objective of this work has been to develop and test thermodynamic models for the reactions of trace elements with chlorine and sulfur in the gasification processes of recycled fuels. In particular, the chemical reactions of trace elements with main thermochemical conversion products, main ash components, and bed and sorbent material are implemented into the model. The possibilities of gas cleaning devices in condensing and removing the trace element compounds are studied by establi…

Tracking trace elements from soil to Lebanese bread and Populations Exposure

2021

In Lebanon, the agri-food industry represents 18% of the industrial sector and yet food safety remains a major problem. In this interdisciplinary thesis, we followed the Trace Elements (TEs) in the Lebanese white bread sector "from farm to fork" based on the reality on the ground, and on two links in the sector: (i) the geogenic or anthropogenic origin of TEs present in the soil and their transfer to the wheat grain, for which 10 plots cultivated in wheat, covering the diversity of soils, irrigation practices and anthropogenic environments of the central Bekaa were chosen ; (ii) the exposure of populations to TEs present in bread, for which a survey of consumption habits across Lebanon was …

Food and Environment: Trace Element Content of Hen Eggs from Different Housing Types

2013

AbstractEleven trace elements (Ba, Cu, Fe, Mn, Ni, Pb, Rb, Se, Sr, V, Zn) were quantitatively determined in hen egg samples collected from different poultry housing types (large-scale poultry farms, organic farms and domestic farms) over the territory of Latvia. Samples were wet digested and quantitatively analysed by total reflection X-ray fluorescence spectrometry (TXRF). The accuracy of analytical method was verified with analysis of certified reference material NCS ZC73017 (GSB-10)-Apple. The most variable range of concentrations and the highest content of elements were determined for hen egg samples derived from organic farms, while egg samples from domestic farms and poultry farms mos…

Geochemical investigation of trace metal pollutants in the Oreto river, Palermo (Italy)

2022

In the past, three main rivers, named Kemonia, Papireto and Oreto, were present in the plain of Palermo, in northwestern Sicily. Today, only the latter one has been preserved from the unregulated urban expansion. Fortunately, over the last ten years, attention and consciousness towardsthe Oreto river and its delicate ecosystem has grown considerably, also thanks to many associations and citizens’ committees involved in protecting, preserving and valorising the precious area. In this context, our study is focused on a hydrogeochemical investigation of its surface water quality. The Oreto river flows for about 20 km within a catchment area of about 130 km2. Over the past three years, numerous…