Mapping of natural radioactivity in soils of Kufa districts, Iraq using GIS technique

This work aims to detect and draw the natural radioactivity levels of uranium-238, thorium- 232, and potassium-40 in soil samples taken from Kufa districts, Najaf governorate, Iraq. The detection system used in the study is NaI(Tl) with a 3 x 3 dimension, while maps are drawn by the geographic information system (GIS). Radiological parameters in all samples of the present study due to a specific activity for U-238, Th-232, and K-40 were calculated. The results of the average value with standard error in all samples of the present study for U-238, Th-232, K-40, and U-235 were 6.2 +/- 0.74, 6.41 +/- 0.82, 278.10 +/- 19.43, and 0.28 +/- 0.03 Bq/kg, respectively. The specific activity of Uranium-238, Thorium-232, potassium-40, and Uranium-235 found in all soil samples were within the safety limit (33 Bq/kg for U-238, 45 Bq/kg for Th-232, and 420 Bq/kg for K-40) reported by UNSCEAR, except three samples have potassium-40 higher than the safety limit. In addition, the results of radiological parameters were all found to be below OECD and UNSCEAR safety limits. Generally, the average of specific soil activity was arranged with potassium-40 > thorium-232 > uranium-238. The results of investigating natural radioactivity and radiological parameters of soil samples from Kufa districts were radiologically safe.

Automated summary

This study aimed to detect and map the natural radioactivity levels of uranium-238, thorium-232, and potassium-40 in soil samples from Kufa districts, Najaf governorate, Iraq. The results showed that the specific activity of these radionuclides in all soil samples were within the safety limits, except for three samples with higher potassium-40 levels.