Using energy-dispersive X-ray fluorescence analysis with a Ti-filtered x-ray tube it was possible to determine the concentrations of several elements, such as K, Ca, Ti, Mn, Fe, Cu, Zn, Br, Rb, Sr, Zr and Pb, at ppm levels in radish plants (root and foliage) cultivated in soils treated with concentrations of 10, 20 and 30 t ha −1 of organic compost from urban garbage. A significant increase was observed in the concentrations of K, Ca, Mn, Fe, Zn, Rb and Pb in radish plants cultivated in the treated soils in comparison with a control soil. The results suggest that radish plants can be used as bioindicator of contamination of agricultural soils.

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X-ray fluorescence with synchrotron radiation total reflection was used to analyze the atmospheric particulate collected in Campinas, SP, Brazil, in fine and coarse fractions, using a stacked filter unit. After treatment with acid solution and pipetting on to Perspex disks, the samples were measured at the x-ray fluorescence beamline at the National Synchrotron Light Laboratory (LNLS), Campinas, using a polychromatic beam for sample excitation. The detection limits obtained ranged from 0.3 to 8.9 ng m −3 for the majority of the elements. The data obtained were treated using analysis receptor models of the principal components, then absolute principal component analysis was applied to obtain the contribution of each source to the total of both particulate fractions. Four sources were identified for the fine fraction for autumn/winter and summer periods: (1) soil dust (22 and 29%); (2) industry (26 and 23%); (3) sulfate (23 and 20%); (4) motor vehicle (22 and 20%); and 7% and 8% non-explained, in the autumn/winter and summer periods, respectively. In coarse fraction analysis, two sources were identified for the autumn/winter and summer periods and with similar rates for source contribution. The obtained sources were: (1) soil dust (77 and 78%); (2) industry (18 and 16%); and non-explained rates of 5 and 6%, in the autumn/winter and summer periods, respectively.

Pasteurization is a thermal treatment applied to the milk used in human milk banks so as to provoke the thermic inactivation of pathogenic micro-organisms, with the aim of avoiding contamination of milk that will be offered to new-born infants in clinical conditions very often demanding special care. The literature has very little data available relating to the effect of pasteurization on the concentration of oligo-elements in human milk. The objective of this study was to evaluate the effect of pasteurization on the concentrations of iron (Fe), copper (Cu) and zinc (Zn) in the colostrum of mothers of pre-term (PT) and term (T) infants. Samples were collected from the day of birth to the seventh day after birth. The oligo-elements were analyzed using the total reflection Xray fluorescence technique with synchrotron radiation. The following results of Fe, Cu and Zn (means9/SD) were obtained for the PT and T colostrum samples, non-pasteurized and pasteurized, respectively:

An X-ray tube with a Mo target and Zr filter, operated at 45 kV/20 mA, was used to excite samples (5 microL deposited on a quartz support) and the total reflection angle condition was obtained with a double reflector module built with two 10-cm-long 7-mm-thick quartz crystals placed 50 microns apart. A high-resolution spectrometer based on a Si(Li) detector coupled to a multichannel analyzer was used for X-ray detection and the spectra were interpreted with the AXIL software. The system was calibrated with standard chemical solutions containing Cr, Fe, Cu, Zn, and Pb, and Y was used as an internal standard to correct eventual geometric errors and high-voltage instabilities of the X-ray generator. The limits of detection were 19, 9, 5, and 4 ng/mL for Cr, Fe, Cu, and Zn, respectively, analyzed through characteristic K alpha X-rays, and 7 ng/mL for Pb, through L alpha X-rays, considering 50 microL samples deposited and dried on a quartz support, to be excited/detected for 1000 s.