Radon and Thoron Levels in and Around Tumkur

The book assesses natural radioactivity in industrial areas and workplaces around Tumkur, Karnataka, through measurements of gamma radiation, radionuclides, radon, thoron and their progeny. Higher gamma radiation and radon/thoron levels were observed near stone-crushing industries. Concentrations of 226Ra, 232Th and 40K were relatively higher in certain geological formations, particularly pink porphyritic granite, while hazard indices remained within acceptable limits. Groundwater analysis showed a strong relationship between radium and radon concentrations. Radon and thoron levels were generally below the ICRP action level, with higher values during winter than summer. The total annual effective dose from natural radiation was estimated at 3.7343 mSv y¿¹, with radon, thoron and their progeny making the major contribution. Overall, the study provides baseline information on environmental radioactivity and highlights the need for continued monitoring and suitable radiological protection measures.