Natural radionuclides and dose estimation in natural water resources from Elba protective area, Egypt

The concentrations of the natural radionuclides 226 Ra, 232 Th and 40 K in 15 different water samples from Elba protective area, south-eastern desert of Egypt, have been determined using NaI(Tl) detector. Gamma ray spectrometric analysis was performed and the concentrations obtained for each of the radionuclides expressed in Bq l -1 ranging from 1.6 to 11.1 for 226 Ra, 0.21 to 0.97 for 232 Th and 9.1 to 23 for 40 K. A reasonable correlation was found between 226 Ra, 232 Th concentrations and pH, although no general trend was observed with conductivity and total dissolved solids. The mean effective doses of 0.56 mSv y -1 for 226 Ra, 0.065 mSv y -1 for 232 Th and 0.04 mSv y -1 for 40 K were estimated for the ingestion of these waters by adults.