Measurement of Radon Concentrations and Surface Exhalation Rates using CR-39 detector in Soil Samples of Al-Diwaniyah Governorate, Iraq

Natural radioactivity in the soil is considered a major indicator of radiological contamination. Primordial radionuclides are the main source of natural radioactivity. Natural radioactivity transfers radionuclides into the environment and poses radiation hazards to people's health. Therefore, the present study aimed to determine the radon concentration and surface exhalation rate in soil samples collected from different locations of industrial, agricultural, and residential of Al-Diwaniyah governorate, southern Iraq.

In the present study, five different depths of 0, 10, 20, 30, and 40 cm were taken from each location. The radon concentration and exhalation rate were measured using CR-39 detectors (Pershore Moulding Ltd, UK). The CR-39 detectors were left inside plastic cans with soil samples. The tracks of nuclear particles were recorded using an optical microscope.

Results of the present study showed that the radon concentrations in soil samples ranged from 163.58 to 689.89 Bq/m3 with a mean value of 350.64 Bq/m3, while surface exhalation rate was found to be ranged from 0.015 Bq/m2.h to 0.063 Bq/m2.h with an average value of 0.031 Bq/m2.h. The obtained results demonstrated that the radon concentration and exhalation rate decreased with increased depth of soil.

Based on the current findings, it was found that radon concentrations in all the examined soil samples were within the acceptable value of 600 Bq/m3, according to the International Commission on Radiological Protection and International Atomic Energy Agency. However, the sample S13 from AL-Hamad village with a mean value of 642.51±22.95 Bq/m3 was an exception.