Determination of ²²⁶Ra in mineral waters by high-resolution inductively coupled plasma mass spectrometry after sample preparation by cation exchange

²²⁶Ra in mineral waters was determined by high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). The analytical result was compared with that by liquid scintillation counting. A cation exchange technique was used for separation of ²²⁶Ra from matrix elements in the water samples. Analyte recovery efficiency was better than 97% and matrix separation efficiency was higher than 99% for Ca, the major matrix element. The method detection limit of 0.01 pg L^-1 was achieved which was much lower than the United States Environmental Protection Agency required detection limit of 1 pg L^-1. ²²⁶Ra concentrations in several Korean mineral waters are presented.