Radon in soil and its concentration in the atmosphere around Mysore city, India

Radon concentration in soil-gas and in the atmospheric air has been studied around Mysore city (12°N and 76°E) using Solid State Nuclear Track Detectors. The radon in soil-gas is found to be higher at a depth of 1 m than at a depth of 0.5 m from the ground surface. The higher radon concentration in soil was observed near Chamundi Hills and Karigatta village with average values of 5.94 kBq.m⁻³ and 5.32 kBq.m⁻³ at 1 m depth from the ground surface. Seasonal variations in radon in soil gas shows that, the concentration is lower in summer with an average value of 0.60 kBq.m⁻³ and higher in monsoon season with an average value of 4.70 kBq.m⁻³. Estimation of ²²⁶Ra in soil at these locations is also made using HPGe detector. The activity of ²²⁶Ra, varies from 4.82 to 74.23 Bq.kg⁻¹ with an average value of 32.11 Bq.kg⁻¹. Radon concentrations in soil-gas shows good correlation with the activity of ²²⁶Ra in soil with a correlation coefficient of 0.76