Comparison of analytical methods used to determine U, U and Pb from sediment samples by alpha, beta and gamma spectrometry

An intercomparison of the methodology (alpha, beta and gamma spectrometry) used for U, U and Pb determination was carried out based on 38 sediment samples. The activity range of the samples varied from 10--700 Bq/kg for Pb, 1--35 Bq/kg for U and 10--800 Bq/kg for U. Results obtained using the three methods were not statistically different at high activity levels, but agreement between the results decreased at lower sample activity levels. For Pb, the smallest difference was found between alpha and gamma spectrometry. A good correlation between results from alpha and gamma spectrometry was observed over the whole activity range. In beta spectrometry, the results were slightly higher than those obtained by alpha or gamma spectrometry due to the impurity of Ra. In U analysis, good correspondence was observed between U determined by gamma and alpha spectrometry, particularly at higher U activity concentrations over 100 Bq/kg. In U analysis, attention needs to be paid to interference from Ra and its reduction.