Natural radionuclides in bottled drinking waters produced in Croatia and their contribution to radiation dose Original Research Article

Activity concentrations of 234U, 238U, 226Ra, 228Ra, 210Po and 210Pb in all Croatian bottled drinking natural spring and natural mineral water products, commercially available on the market, were determined. The samples originated from various geological regions of Croatia.Activity concentrations of measured radionuclides are in general decreasing in this order: 234U > 238U > 226Ra > 228Ra > 210Pb > 210Po and 226Ra > 228Ra > 234U > 238U > 210Pb > 210Po for natural spring and mineral waters, respectively.Based on the radionuclide activity concentrations average total annual effective ingestion doses for infants, children and adults, as well as contribution of each particular radionuclide to total dose, were assessed and discussed. The highest doses were calculated for children from 7 to 12 years of age, which makes them the most critical group of population. All values for each type of water, as well as for each population group, were well below the recommended reference dose level (RDL) of 0.1 mSv from one yearʹs consumption of drinking water according to the European Commission recommendations from 1998.Contribution of each particular radionuclide to total doses varied among different water types and within each water type, as well as between different age groups, where the lowest contribution was found for uranium isotopes and the highest for 228Ra.