Measuring radon and radium concentrations in 50 samples of drinking water sources of mashhad

Radon and its radioactive progenies in indoor places are recognized as the main sources of public exposure from the natural radioactive sources. The tap water used for drinking and other household uses can increase the indoor radon level. In the present research data on radon concentrations in the water samples of Mashhad city has provided. Water samples were collected from various places and supplies of public water used in Mashhad. Then radon concentration has been measured by PRASSI system tree times for each sample in this research. Result shows about 75% of water samples have radon concentration gather than 10Bq/L which advised EPA as a normal level. According to measurements data, the mean radon concentration of all samples was 16.238 ± 9.322 Bq/L. The annual mean effective dose in stomach and long are 42.674 ± 24.525 and 45.305 ± 26.037 μSv/y, respectively, per person of Mashhad population which is more then 4 millions people. Results show about 75% of water samples have radon concentration gather than 10Bq/L as advised of EPA normal level. The radon and radium concentrations in drinking water samples actually used by people in Mashhad in some regions are not low enough and below the EPA proposed limits. Since a main section of radon come in body is due to drinking and household water, and for improvement of the social health level, we suggest using the low radon level water source, or public water supplies authority reducing the radon in the drinkable water before using by people.