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Macro-and microelement contents of five medicinal plants (Taraxacum officinale Weber, Eucalyptus globulus Labill, Plantago lanceolata L., Matricaria chamomilla L. and Mentha piperita L.) and their infusions were evaluated by the combined use of x-ray fluorescence (WDXRF and EDXRF, bulk raw plants) and inductively coupled plasma (ICP-MS and ICP-AES, infusions) techniques. The analytical methods allow the determination of 17 elements (Na, Mg, Al, Si, P, S, K, Ca, Ti, Mn, Fe, Cu, Zn, As, Rb, Sr, and Pb) both in plants and in the infusions. The use of XRF techniques offer a good multielemental approach for the rapid quality control of bulk raw plant materials whereas ICP techniques are well suited for the analytical control of infusions in order to ascertain the nutritional role of medicinal plants and the daily dietary intake.

Petrological, geochemical and Nd-isotopic analyses have been carried out on rock samples from the Rainbow vent field to assess the evolution of the hydrothermal system. The Rainbow vent field is an ultramafic-hosted hydrothermal system located on the Mid-Atlantic Ridge, characterized by vigorous high-temperature venting (~365ºC) and unique chemical composition of fluids: high chlorinity, low pH and very high Fe and REE contents (Douville et al. 2002). Serpentinisation has occurred under a low-temperature (<270ºC) retrograde

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The purpose of the present work was to investigate whether the distribution of trace elements in human teeth of the Neolithic period in Portugal can reflect environmental conditions, dietary habits and uptake of some elements from the surrounding soil. An x‐ray fluorescence set‐up with microprobe capabilities, installed at the LURE synchrotron (France), was used for elemental analysis of teeth. The resolution of the synchrotron microprobe was 100 µm and the energy of the incident beam was 18 keV. The synchrotron microprobe concentration profiles for V, Mn, Fe, Cu, Zn, Sr and Pb in different regions of the tooth are discussed and correlated with the results obtained by cranio‐facial studies. The Mn and Fe concentrations were much higher in Neolithic teeth than in those of present humans. This may suggest uptake of both elements from the soil. Low concentration levels of Sr were found, which can be correlated with dietary habits. Moreover, the Pb concentration was very low in all the teeth analysed, in agreement with the low pollution levels of this element in this population. All samples were analysed without any chemical preparation. Copyright © 2004 John Wiley & Sons, Ltd.

The elemental concentration in buried human bones is studied by energy dispersive x‐ray fluorescence. Several cortical and trabecular bones: skulls, peroneus, mandibles, tibias, femurs, ribs, vertebras and omoplates, belonging to a population dating to the Middle Ages were analysed. The purpose of this study is to compare the behaviour of the different structures of the several bones during the diagenetic process affecting bone during burial. Quantitative analysis was performed for K, Ca, Zn, Sr, Ti, Mn, Fe and Pb and cluster analysis was achieved considering the elemental concentrations for the different bones. There is a clear distinction for bone association regarding Ca, Zn, Sr and K, Mn, Fe, Ti and Pb in the several bones. These results do not allow a clear categorization into cortical and trabecular bones for some of the samples studied, as far as distinguishing between the remains of the original bone and the environmental contamination from the surrounding soil. Copyright © 2007 John Wiley & Sons, Ltd.

X-ray fluorescence spectrometry was used for the quantitative analysis of healthy liver, brain and kidney tissues and the corresponding tissues from subjects suffering from liver cirrhosis. All samples were collected post-mortem and frozen until analysis. A sample of each tissue for the same individual was collected, in order to find any correlation between the elemental concentrations in the different tissues. Age, sex, cause of death and specific diseases were registered. All samples were studied without any chemical treatment. Concentrations of minor and trace elements in each tissue were obtained for 14 elements. Three groups of elements were considered. The first was K and Ca, present in relatively high concentrations in all tissues and known as normal constituents of all living matter. They are essential to cellular metabolism. The second group was Mn, Fe, Cu, Zn, Se, Br, Rb and Sr, which are also essential elements, but may induce toxic effects if present in high concentrations. There is a narrow range between beneficial and toxic concentrations for these elements. The third group was the toxic elements Co, Ni, As and Pb, which normally induce pathological disorders in the organism, even in small concentrations. This work is a contribution to the better understanding of trace element accumulation in human liver, kidney and brain and the possible correlation between abnormal concentrations of some elements in tissues of subjects suffering from cirrhosis. A very important factor is also the relative concentration of the elements with respect to one another and the correlation between the elemental content in the different tissues. Very low concentrations for Ni, As and Sr were found in the samples analysed, at the level of the detection limit. Higher concentrations of Co, Fe and Pb and lower values of Zn and Se were found in liver cirrhosis samples compared with healthy tissues. Brain samples from subjects affected with cirrhosis showed enhanced levels of Pb. In kidney, increased amounts of Zn were found in tissues from subjects with cirrhosis.