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A procedure for the non-destructive elemental analysis of soils using wavelength-dispersive x-ray fluorescence spectrometry (WDXRF) is proposed. The determination of minor and trace elements is considered. It does not require any sophisticated treatment of the sample. The method was validated using certified soil standard reference materials, obtaining satisfactory agreement between the WDXRF results and the certified values. The multielemental information provided by the proposed method was used to model a classification of Argentine soils by chemometric analysis.

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Honey is produced by Apis Mellifera bees, primarily from floral nectars. The bees are estimated to forage on plants growing in a relatively large area of more than 7 km2. If it is assumed that any hive includes at least 1000 worker bees and that each of them forages on 1000 flowers per day, the honey produced daily can be considered the outcome of at least one million interactions. In this way, the foraged area is effectively sampled for trace elements. The mineral content of honey is recognized as an environmental indicator. In this work, it is used as an indicator of toxic metal contamination in an extensive area in the central‐west of Argentina. Metal identification and quantification was done by total reflection x‐ray fluorescence (TXRF). The level of contamination was evaluated taking into account the concentration values suggested by the Codex Alimentarium Commission. Chemometric tools were employed to relate the honey composition to the environmental contamination of the studied areas. Copyright © 2007 John Wiley & Sons, Ltd.

Hair arsenic concentrations were measured in 50 dogs living at Barrio Los Alamos, Gran Buenos Aires, Argentina, to evaluate the contamination risk in humans living in an area with arsenic levels higher than maximum allowed limit of 10 mg l À1 . This region belongs to the zone in Argentina with Chronic Endemic Hydroarsenicism. Quantification of the samples was carried out using total reflection X-ray fluorescence technique after a sample preparation procedure. Independent of genre, age and breed, hair dogs from Los Alamos had significantly higher arsenic concentrations than a set of ten dogs used as blank coming from a free arsenic area. These found levels in hair indicated a chronic contamination in dogs and suggest similar presumption in humans. Results of this study encourage the potential of using pets as biomarkers of environmental metal contamination.

The chemical control of impurities in nuclear materials is indispensable in order to ensure efficient operation of the reactors. The maximum concentration admitted depends on the elements and in most cases is in the parts per billion range. Conventional analytical methods require a preconcentration treatment of the sample and a previous separation of the matrix (uranium). In this work, we investigated the use of total reflection x-ray fluorescence with synchrotron radiation excitation as an alternative methodology for the determination of impurities in nuclear materials, namely K, Ca, Ti, Cr, Mn, Fe, Ni, Cu and As. The detection limits obtained were in the range 0.1-20 ng ml −1 for a 1000 s counting time.