Radon gas determination and radiological risk in tap water of Al-Muthanna governorate, Iraq

Assay of the water samples is the preferred way to know the natural radioactivity levels that are very important for the protection of the environment and human health. Research aims to determine the radon gas levels and its radiological hazard risk in tap water from different locations in nature (agricultural, industrial and residential) of Al-Muthanna governorate, by effective technique of CR-39 alpha detector. The results of the investigation showed that the values of the radon concentrations CRn ranged between 2.16±0.15 Bq/l to 4.32 ± 0.18 Bq/l, with the average value of CRn is 3.22 ± 0.18 Bq/l. The mean values of the radiological hazards such as annual effective dose (AED), radon exhalation rates (RER), and dissolved radon gas content (Cd) were 11.76 µSv/y, 0.0039 Bq/m2.h and 58.4 Bq/l, respectively. It was found that the mean value of the radon gas concentration in all the studied tap water samples were within the acceptable limits according to the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and United States Environmental Protection Agency (US EPA).