Natural radioactivity in tap waters from the private wells in the surroundings of the former Žirovski Vrh uranium mine and the age-dependent dose assessment

Activity concentration of 238U, 234U, 226Ra, 228Ra, 210Pb and 210Po in tap water from selected springs and private wells in the area of the former uranium mine at Žirovski Vrh were determined. A total of 22 tap water samples were collected at consumer’s houses. The results show that the activity concentrations of uranium in water samples are in range (0.17–372) and (0.22–362) mBq L−1 for 238U and 234U, respectively. Radium activity concentrations are in range (0.14–16.7) and (0.9–11.7) mBq L−1 for 226Ra and 228Ra, respectively. 210Po activity concentration is in range (0.28–8.0) mBq L−1 and can be regarded as the lowest amongst all analysed radionuclides. The range for 210Pb is (0.5–24.6) mBq L−1. Based on the results obtained for activity concentrations of six radionuclides, the committed effective dose for three different age groups of population were estimated. It was found that the committed effective dose was well below the recommended value of 100 μSv year−1, ranging from 2.3 to 34.3 μSv year−1 for adults, from 3.5 to 32.0 μSv year−1 for children (7–12 years) and from 3.0 to 23.3 μSv year−1 for infants.