A sensitive method based on HDEHP extraction and LSS for the determination of 90Sr in solid samples

An improved and rapid method is described for the determination of Sr-90 in environmental samples, through the separation of the daughter Y-90 at equilibrium. The procedure is based on the HDEHP solvent extraction in combination with liquid scintillation spectrometry (LSS). A low background QuantulusO has been optimized for low level counting of Cerenkov radiation emitted by the hard b-emitter Y-90. The counting efficiency was 60% and the background 0.53 cpm. The reliability and reproducibility of the method have been checked using IAEA reference materials. The chemical recovery for Y-90 extraction ranges from 83 to 90%.