Dose assessment and radioactivity of the mineral water resources of Dimeh springs in the Chaharmahal and Bakhtiari Province, Iran

. One of the main sources of public exposure from natural radioactivity is radium and radon and its short lived decay products. The aim of this study is focused on determining the concentration of mentioned radionuclides in the mineral water resources in one of the highest altitude regions (Zagros Mountains), the Chaharmahal and Bakhtiari province, in South-West Iran, namely the Dimeh springs. Eighty drinking spring water samples were taken from the Dimeh springs (ten samples for each spring) to determine radium-226 (226Ra) and radon-222 (222Rn) concentrations using the emanation method and a liquid scintillation counting method, respectively. The results of this study showed that the effective dose from the consumption of drinking water of Dimeh springs (6.4 žSv/y) is not comparable to the other annual effective dose such as inhalation of radon and its products in cosmic and terrestrial rays published by one of the authors previously. Also, the annual effective dose measured here is much lower than the worldwide mean value 0.45 mSv reported by USCEAR, 2000 and is also low enough and below the proposed limits in other countries and this is the reason why this sources of water may be considered as safe drinking water in the region.