Natural radionuclides in Austrian mineral water and their sequential measurement by fast methods

Ten samples of Austrian mineral water were investigated with regard to the natural radionuclides 228Ra, 226Ra, 210Pb, 210Po, 238U and 234U. The radium isotopes as well as 210Pb were measured by liquid scintillation counting (LSC) after separation on a membrane loaded with element-selective particles (Empore™ Radium Disks) and 210Po was determined by α-spectroscopy after spontaneous deposition onto a copper planchette. Uranium was determined by ICP-MS as well as by α-spectroscopy after ion separation and microprecipitation with NdF3. From the measured activity concentrations the committed effective doses for adults and babies were calculated and compared to the total indicative dose of 0.1 mSv/a given in the EC Drinking Water Directive as a maximum dose. The dominant portion of the committed effective dose was due to the radium isotopes; the dose from 228Ra in most samples clearly exceeded the dose from 226Ra.