Revisited digestion methods for trace element analysis in human hair

Abstract Background The human hair is a potential material for assessing the exposure to environmental contaminants and tracing human mobility. Although various digestion methods have been proposed for determining trace elements in the human hair, there is no consensus about the best method among them yet. Findings We examined five different methods in order to determine the best method yielding the most accurate and precise data of trace elements in the human hair using two certified reference human hairs (IAEA085 and IAEA086) under controlled conditions (temperature, the volume of hydrogen peroxide (H2O2), and the number of digestion). Results showed that a high temperature of 160 °C yields better recovery rates than a low temperature of 70 °C. Furthermore, the additional input of H2O2 increases the recovery rate from 90 to 102%, and the two-time digestion also promotes the recovery rate. Conclusions This study suggests that although the combination of high temperature (160 °C), high volume of H2O2 (0.4 mL), and two-time digestion yields the most accurate and precise data of trace elements in the human hair, the digestion method should be carefully selected depending on the content of organometallic cation.

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Parental magma composition of the Main Zone of the Bushveld Complex: Evidence from in-situ LA-ICP-MS trace element analysis of silicate minerals in the cumulate rocks

10.5194/egusphere-egu2020-17903 ◽

2020 ◽

Author(s):

Shenghong Yang ◽

Wolfgang D. Maier ◽

Belinda Godel ◽

Sarah-Jane Barnes ◽

Eero Hanski ◽

...

Keyword(s):

Trace Elements ◽

Trace Element ◽

Bushveld Complex ◽

Trace Element Analysis ◽

Parental Magma ◽

Main Zone ◽

Element Analysis ◽

Silicate Minerals ◽

Incompatible Elements

<p>In-situ trace element analysis of cumulus minerals may provide a clue to the parental magma from which the minerals crystallized. However, this is hampered by effects of the trapped liquid shift (TLS). In the Main Zone (MZ) of the Bushveld Complex, the Ti content in plagioclase grains shows a clear increase from core to rim, whereas most other elements (e.g., rare earth elements (REEs), Zr, Hf, Pb) do not. This is different from the prominent intra-grain variation of all trace elements in silicate minerals in mafic dikes and smaller intrusion, which have a faster cooling rate. We suggest that crystal fractionation of trapped liquid occurred in the MZ of Bushveld and the TLS may have modified the original composition of the cumulus minerals for most trace elements except Ti during slow cooling. Quantitative model calculations suggest that the influence of the TLS depends on the bulk partition coefficient of the element. The effect on highly incompatible elements is clearly more prominent &#173;&#173;than on moderately incompatible and compatible elements because of different concentration gradients between cores and rims of cumulate minerals. This is supported by the following observations in the MZ of Bushveld: 1) positive correlation between Cr, Ni and Mg# of clinopyroxene and orthopyroxene, 2) negative correlation between moderately incompatible elements (e.g., Mn and Sc in clinopyroxene and orthopyroxene, Sr, Ba, Eu in plagioclase), but 3) poor correlation between highly incompatible elements and Mg# of clinopyroxene and orthopyroxene or An# of plagioclase. Modeling suggests that the extent of the TLS for a trace element is also dependent on the initial fraction of the primary trapped liquid, with strong TLS occurring if the primary trapped liquid fraction is high. This is supported by the positive correlation between highly incompatible trace element abundances in cumulus minerals and whole-rock Zr contents.</p><p>We have calculated the composition of the parental magma of the MZ of the Bushveld Complex. The compatible and moderately incompatible element contents of the calculated parental liquid are generally similar to those of the B3 marginal rocks, but different from the B1 and B2 marginal rocks. For the highly incompatible elements, we suggest that the use of the sample with the lowest whole-rock Zr content and the least degree of TLS is the best approach to obtain the parental magma composition. Based on calculation, we propose that a B3 type liquid is the most likely parental magma to the MZ of the Bushveld Complex.</p>

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Preface

Pure and Applied Chemistry ◽

10.1351/pac20067801viii ◽

2006 ◽

Vol 78 (1) ◽

pp. viii

Author(s):

Michael Bickel

Keyword(s):

Trace Elements ◽

Trace Element ◽

Trace Element Analysis ◽

The Body ◽

Research Centre ◽

Food Contaminants ◽

Joint Research ◽

Element Analysis ◽

Fortified Food ◽

Animal Metabolism

Trace elements may have different functions in human and animal metabolism: some are toxic (e.g., Hg), others are essential to maintain good health (e.g., Ca), or they can be essential but also toxic, depending on the concentration in the body or in parts thereof (e.g., Se).The importance of various aspects of trace elements in relation to food is steadily increasing in the perception of the consumer and the respective authorities: food contaminants, essential and toxic elements, bioavailability and speciation, nutritional value and fortified food, reliable measurement of contents, etc. In addition, through the many minor and major food-related incidents during recent years the consumer is becoming more concerned about the quality and safety of food. As a result, research and development efforts in this area have also been increased and/or been redirected.TEF-2 was organized in Brussels 7-8 October 2004 by the Institute of Reference Materials and Measurements of the Joint Research Centre of the European Commission, with the support of the Department of Food Analysis, Institute of Agricultural and Food Biotechnology of the University of Warzaw, Poland and the Centre National de la Recherche Scientifique, France. It was carried through under the auspices of IUPAC.The objectives laid down for the symposium were- presenting state-of-the-art analytical methods for the enforcement of legal limits of trace elements in food;- disseminating new ideas and findings within the scientific community;- providing a forum for the exchange of new knowledge and experience between R&D, authorities, and industry; and- bringing together experts in the field with newcomers.TEF-2 was attended by 93 participants from 60 different institutions in 23 countries. It consisted of 26 lectures and 56 posters, structured according to the following four main topics:- trace elements in the food chain (from the environment to shelf product) including the effects of processing and of legislation- trace element bioavailability-toxicological and nutritional aspects- fortified food and supplementation legislation, manufacturing and labeling, standards- advances in trace element analysis in food matricesIt was emphasized that the field of trace elements in food is a lively research area, which generates interest and involvement from researchers, authorities, and industry, of course triggered and nurtured by the equally high interest of the consumer. A selection of the invited contributions to TEF-2 is presented in the subsequent seven papers in this issue.The importance of scientific exchange in this field was, again, recognized during TEF-2. Therefore, the continuation of this series of conferences was discussed, and the venue for the subsequent TEF-3 was decided. It will be organized by R. Lobinski of CNRS in Pau, France, at the beginning of October 2008.Michael BickelConference Editor

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Efficiency of acid digestion procedures for geochemical analysis of tungsten mining wastes

Geochemistry Exploration Environment Analysis ◽

10.1144/geochem2021-034 ◽

2021 ◽

pp. geochem2021-034

Author(s):

Z. Han ◽

M. Edraki ◽

A. Nguyen ◽

M. Mostert

Keyword(s):

Trace Element Analysis ◽

Major Elements ◽

Critical Element ◽

Digestion Method ◽

Element Analysis ◽

Geochemical Composition ◽

Alkali Fusion ◽

Global Demand ◽

Complete Digestion ◽

Digestion Methods

Tungsten is a critical element used in the industry with increasing global demand. There are millions of tons of current and legacy mineral processing tungsten tailings worldwide that can potentially contaminate the environment and pose human health risks. These tailings could also potentially turn into valuable resources if we thoroughly characterise their geochemical composition. In this study, an innovative method was developed to achieve the complete digestion of tungsten tailings. We tested three different digestion methods (hotplate digestion, bomb digestion, and ColdBlockTM digestion) and compared the results. Additionally, an alkali fusion for major element analysis was also applied and tested. The results showed that alkali fusion is the best method for major elements analysis, while bomb digestion is the best method for tungsten and trace element analysis, but volatile chlorite loss was also observed. The hot plate digestion method for tungsten mine tailings was not recommended, because of poor recoveries of trace elements compared to the bomb digestion method. The quick and safer ColdBlockTM digestion method could be used for Bismuth (Bi), Molybdenum (Mo), and several rare earth element analyses indicated by their recoveries being close to the bomb digestion method.

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Trace-Element Analysis in Clinical Chemistry

Clinical Chemistry ◽

10.1093/clinchem/17.6.461 ◽

1971 ◽

Vol 17 (6) ◽

pp. 461-474 ◽

Cited By ~ 125

Author(s):

Henry A Schroeder ◽

Alexis P Nason

Keyword(s):

Trace Elements ◽

Trace Element ◽

Clinical Chemistry ◽

Trace Element Analysis ◽

Present Knowledge ◽

Human Metabolism ◽

Element Analysis ◽

Toxic Trace Elements ◽

Essential Trace Elements ◽

Clinical Conditions

Abstract Present knowledge of human bodily contents and concentrations in blood, urine, and hair of 11 essential trace elements and 17-22 nonessential inert or toxic trace elements is reviewed and summarized. Analyses of trace elements are applicable as diagnostic aids and indices for therapy in a number of clinical conditions. Techniques are not difficult, and analyses will probably become more or less routine for many diseases in which primary or secondary abnormalities are manifest. Trace elements play fundamental roles in human metabolism.

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Multipoint Background Analysis: Gaining Precision and Accuracy in Microprobe Trace Element Analysis

Microscopy and Microanalysis ◽

10.1017/s1431927618015660 ◽

2019 ◽

Vol 25 (1) ◽

pp. 30-46 ◽

Cited By ~ 5

Author(s):

Julien M. Allaz ◽

Michael L. Williams ◽

Michael J. Jercinovic ◽

Karsten Goemann ◽

John Donovan

Keyword(s):

Mass Spectrometry ◽

Trace Elements ◽

Trace Element ◽

Spectral Region ◽

Trace Element Analysis ◽

Background Intensity ◽

Element Analysis ◽

Accuracy And Precision ◽

Background Measurement ◽

Background Curvature

AbstractElectron microprobe trace element analysis is a significant challenge. Due to the low net intensity of peak measurements, the accuracy and precision of such analyses relies critically on background measurements, and on the accuracy of any pertinent peak interference corrections. A linear regression between two points selected at appropriate background positions is a classical approach for electron probe microanalysis (EPMA). However, this approach neglects the accurate assessment of background curvature (exponential or polynomial), and the presence of background interferences, a hole in the background, or an absorption edge can dramatically affect the results if underestimated or ignored. The acquisition of a quantitative wavelength-dispersive spectrometry (WDS) scan over the spectral region of interest remains a reasonable option to determine the background intensity and curvature from a fitted regression of background portions of the scan, but this technique can be time consuming and retains an element of subjectivity, as the analyst has to select areas in the scan which appear to represent background. This paper presents a new multi-point background (MPB) method whereby the background intensity is determined from up to 24 background measurements from wavelength positions on either side of analytical lines. This method improves the accuracy and precision of trace element analysis in a complex matrix through careful regression of the background shape, and can be used to characterize the background over a large spectral region covering several elements to be analyzed. The overall efficiency improves as systematic WDS scanning is not required to assess background interferences. The method is less subjective compared to methods that rely on WDS scanning, including selection of two interpolation points based on WDS scans, because “true” backgrounds are selected through an exclusion method of possible erroneous backgrounds. The first validation of the MPB method involves blank testing to ensure the method can accurately measure the absence of an element. The second validation involves the analysis of U-Th-Pb in several monazite reference materials of known isotopic age. The impetus for the MPB method came from efforts to refine EPMA monazite U-Th-Pb dating, where it was recognized that background errors resulting from interference or strong background curvature could result in errors of several tens of millions of years on the calculated date. Results obtained on monazite reference materials using two different microprobes, a Cameca SX-100 Ultrachron and a JEOL JXA-8230, yield excellent agreement with ages obtained by isotopic methods (Thermal Ionization Mass Spectrometry [TIMS], Sensitive High-Resolution Ion MicroProbe [SHRIMP], or Secondary Ion Mass Spectrometry [SIMS]). Finally, the MPB method can be used to model the background over a large spectrometer range to improve the accuracy of background measurement of minor and trace elements acquired on a same spectrometer, a method called the shared background measurement. This latter significantly improves the accuracy of minor and trace element analysis in complex matrices, as demonstrated by the analysis of Rare Earth Elements (REE) in REE-silicates and phosphates and of trace elements in scheelite.

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FUNDAMENTAL INVESTIGATION ON TRACE ELEMENT ANALYSIS IN WOOD SAMPLES USING THE PIXE METHOD

International Journal of PIXE ◽

10.1142/s0129083596000557 ◽

1996 ◽

Vol 06 (03n04) ◽

pp. 511-516

Author(s):

TORU AOKI ◽

YUKIO KATAYAMA ◽

KOHJI YOSHIDA

Keyword(s):

Trace Elements ◽

Cryptomeria Japonica ◽

Radial Direction ◽

Annual Ring ◽

Trace Element Analysis ◽

Concentration Profiles ◽

Element Analysis ◽

Fundamental Investigation ◽

Late Wood ◽

Pixe Method

A fundamental investigation of the PIXE method applied to the measurement of trace elements in wood samples, is described in this work. Yields of the elements added to a sugi (Cryptomeria japonica D. Don) specimen, were almost constant after they were bombarded with radiation up to 600µC. Yields of certain elements in the early wood and the late wood in the same annual ring of the sugi were compared. The yields of Ca, Cu, Zn, Rb and Sr in the late wood were the same or slightly higher than those in the early wood, but Fe and Mn yields in the late wood were higher than those in the early wood. The concentration profiles of Ca, Mn, Fe, Zn and Sr along a radial direction in the stem of the sugi were also determined.

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Identification of Natal Locales of Peregrine Falcons (Falco peregrinus) by Trace-Element Analysis of Feathers

The Auk ◽

10.1093/auk/100.3.560 ◽

1983 ◽

Vol 100 (3) ◽

pp. 560-567 ◽

Cited By ~ 26

Author(s):

Jimmie R. Parrish ◽

David T. Rogers ◽

F. Prescott Ward

Keyword(s):

Trace Elements ◽

Trace Element ◽

Trace Element Analysis ◽

Trace Element Content ◽

Falco Peregrinus ◽

Element Analysis ◽

Peregrine Falcons ◽

Geographic Origins ◽

Multivariate Discriminant ◽

Discriminant Function Analyses

Abstract Samples of secondary remiges collected from nestling Peregrine Falcons (Falco peregrinus) in Alaska and western Greenland were analyzed for trace-element content using instrumental neutron-activation analysis. Concentrations of 14 trace elements were subjected to a series of multivariate discriminant function analyses to ascertain whether or not these concentrations could be used to identify the geographic origins of the birds sampled. Individual falcons from the three areas studied can be placed in their proper natal locale with 100% predictability. Mercury (Hg) was the best individual discriminator for separating sample groupings. Aluminum (A1) and Vanadium (V), in conjunction with Hg, provided the most discriminant trio of elements when various groupings of element concentrations were considered as predictors.

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Trace Element Analysis of Bone from Past Populations in the Peninsula of Yucatan

MRS Proceedings ◽

10.1557/opl.2012.1392 ◽

2012 ◽

Vol 1374 ◽

pp. 227-233

Author(s):

Saul Chay ◽

Mónica Rodríguez ◽

Patricia Quintana ◽

Vera Tiesler

Keyword(s):

Trace Elements ◽

Trace Element ◽

Trace Element Analysis ◽

Justice Department ◽

Element Analysis ◽

Dietary Study ◽

Maya Site ◽

High Degree

ABSTRACTThis dietary study compares concentrations of trace elements in human skeletal series from the municipal cemetery of Xoclán, in Mérida, Yucatan, and a skeletal collection that was donated by the Yucatecan State Justice Department (PGH). The results from these modern samples are to be compared to those obtained from human collections from a colonial cemetery from Campeche and the pre-Hispanic Maya site of Xcambó. Our results indicate that the archaeological series show higher concentrations of Sr compared to the modern populations, both of which showed very similar values. Zn concentrations were similar when the modern values were compared to those derived from the colonial series from Campeche. Xcambó´s population, in turn, shows a high degree of variability in Zn values, which may be due to diagenetic contamination.

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Investigation of the Multielement Capability of Laser-Enhanced Ionization Spectrometry in Flames for Analysis of Trace Elements in Water Solutions

Applied Spectroscopy ◽

10.1366/0003702874868160 ◽

1987 ◽

Vol 41 (1) ◽

pp. 19-26 ◽

Cited By ~ 46

Author(s):

O. Axner ◽

I. Magnusson ◽

J. Petersson ◽

S. Sjöström

Keyword(s):

Trace Elements ◽

Detection Limit ◽

Trace Element Analysis ◽

Frequency Doubling ◽

Ultraviolet Region ◽

Element Analysis ◽

Coumarin 153 ◽

One Step ◽

Trace Elements In Water ◽

First Time

One-step Laser-Enhanced Ionization (LEI) spectrometry of 23 different elements in aqueous solutions has been performed in an acetylene/air flame. All elements were detected by light in the ultraviolet region, produced by frequency doubling of the output from the dye Coumarin 153. This was done in order to investigate the multielement capability of LEI in flames that has been made possible by the recent development of commercially available, widely tunable dyes. Among the elements detected, 9 (As, Au, In, Mn, Pb, Sb, Tl, W, Yb) show detection limits which are superior to those reported in the literature for one-step LEI. The lowest detection limit obtained in this investigation was 1 pg/mL for In. Four of the elements (As, Sb, Yb, W) are reported as being detected by LEI for the first time. The multielement capabilities of LEI as a method for trace element analysis are discussed.

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