Influence of natural radium contamination of barium chloride on the determination of radium isotopes in the water samples using α/β liquid scintillation spectrometry

The determination of radium isotopes in drinking water by liquid scintillation technique requires some reagents that are used for separating radium from water samples. One of the main reagents is BaCl₂·H₂O. This paper presents the study of this compound and shows that barium chloride reagent is naturally contaminated with²²⁶Ra. The ²²⁶Ra activity concentration in BaCl₂·H₂O reagent produced by chemical companies from Poland and other countries is equal to a few dozen Bq/kg. Furthermore, 14 mL of 0.10 M BaCl₂·H₂O solution is the optimum amount which should be used for the chemical procedure. At the optimum amount of barium chloride and 2-hour measurement, the detection limit of 226Ra and 228Ra of the liquid scintillation counting method is equal to 5 and 30 mBq per sample, respectively.