Estimation of Human Radiation Exposure from Natural Radioactivity and Radon Concentrations in Soil Samples at Green Zone in Al-Najaf, Iraq

Ar Specific activity of natural radionuclides namely (238U, 232Th, 40K and 235U) and radon concentrations were measured for soil samples collected from green zone in Al-Najaf city, Iraq. There are three nuclear techniques used in present study NaI(Tl), CR-39 and LR-115 type II) were used to determine these radionuclides. Also, the radiological hazard due to natural radioactivity and radon concentrations were calculated. The average of specific activity for 238U,232Th, 40K and 235U using NaI(Tl) detector were17.48±7.43, 8.59±3.18, 298.31±76.22 and 0.80±0.07Bq/kg, respectively. While the average value of radon concentrations using CR-39 detector and LR-115 type II detector was 579.65±33.30 Bq/m3. The average value of radiological hazard due to natural radioactivity (Raeq., Dr, Eγ, Hex, Hin, Iγ, AEDE and ELCR) were within the permissible limits. Also the average values of radon exhalation rates for all samples were within the permissible limits. In addition, there is a good correlation (r= 0.93) for value of radon concentrations using CR-39 and LR-115 type II detectors. There is a good correlation between specific activity of uranium-238 and radon-222 concentrations were found which it is equal r=0.91. It can be concluded that, measurements have been taken as representing baseline of radionuclides present in the soil of the studied area. Therefore, the probability of occurrence of any radiation health effects is low.