A simple screening method for the determination of 230Th in soil and sediment samples by gamma-spectrometry

A simple and easy to perform method for the determination of Th-230 in soil and sediment samples using gamma-spectrometry is proposed and compared with the more usual procedure using alpha-particle spectrometry. The proposed method involves an efficiency calibration for the specific determination of this radionuclide instead of a complete calibration of the spectra A single density parameter is introduced to correct the efficiencies obtained from the reference sources. The activities of Th-230 determined by gamma-spectrometry and alpha-particle spectrometry are compared. The minimum detectable activity values obtained are completely adequate for Th-230 determination in soil and sediment samples, in which Th-230 activities are usually fairly high. Thus, this procedure is intended as a very easy way to obtain the activity of this radionuclide in these types of samples, at least as a screening method before carrying out other more laborious procedures.