Narrow Results

Trace elements in thick samples of aluminum metal reference standards were analyzed by means of PIXE and ICP-AES. The samples were SRM1258 and SRM1259 from National Institute of Standards and Technology (U.S.A.) and 1-A, 3, 4-A and 83 from Japan light metal association. The observed PIXE spectrum was converted “into that of a hypothetical thin target and it was analyzed using a relative intensity database for thin target. A good agreement was obtained between the certified and the found amount of the trace elements. The analytical results for SRM1258 and SRM1259 obtained by ICP-AES method also agreed well with the present results confirming the analytical accuracy.

PIXE technique was applied to measurement of trace elements in total diet samples collected in Japan for estimation of their daily dietary intake. Results of PIXE analysis were compared with INAA Concentration of Cl, K, Mn and Zn by PIXE analysis well agreed with the results from NAA, while Ca, Fe and Cu showed different results between these two techniques. Preliminary data of elemental concentrations in Mate-cha, a kind of tea popular in South America, determined by ICP-AES indicated a little higher concentration of Cu than that by PIXE and much lower value than that by INAA For Zn. concentrations by PIXE and ICP well agreed to each other, while INAA gave much lower value. Japanese internal radiation doses by ¹³⁷Cs and ⁹⁰Sr were estimated to be 2.30µSv/year and 1.27µSv/year respectively as the effective dose equivalents using the daily intake data obtained for K and Ca.

PIXE technique was applied to the measurement of elements in the placenta, maternal blood and cord blood of human. The elements determined in these samples include Cl, K, Ca, Fe, Cu and Zn. The values obtained by PIXE were compared with those by ICP-AES to test the accuracy of the method. In placental samples, the mean values of K, Fe, Cu and Zn concentrations obtained by the two methods agree, while Ca concentration is lower in PIXE analysis. The values from PIXE, however, show larger variations resulting from inhomogeneity of the placental samples composed of various tissues different in histological functions. In the analysis of blood samples, the results of the two methods agree for Cl, K, Ca, Fe, Cu and Zn, although the standard deviations tend to be larger in PIXE. These results indicate that PIXE is a useful method for the determination of elements in placental and blood samples, although the preparation to homogenize sample is necessary to obtain accurate results.