A simple method for determination of 226Ra in environmental samples by applying α–β coincidence liquid scintillation counting

The α–β coincidence measurement of β-rays from 214Bi and α-rays from 214Po was applied for the determination of 226Ra in environmental samples by combining simple chemical procedures. BaSO4 containing 226Ra was mixed thoroughly in toluene scintillator with thixotropic gel powder. The scintillator mixture was directly counted after the growth of progeny nuclides. The analytical results were in good agreement with those obtained by the conventional method or with the certified value for standard reference materials prepared by NIST. The minimum detectable activity was estimated to be 0.75 mBq for 1 g of soil or 1 l of water for 500 min counting