Abstract
Human exposure to indoor radon, thoron and their progenies has become a serious problem throughout the World. In the current research assessment of indoor radon and thoron and their effect on human beings have been analyzed from 200 various locations (5 samples from each location) of Jodhpur, Jhunjhunu, Bikaner and Nagaur districts of Northern Rajasthan, India made with the help of RAD7 technique. The radon and thoron levels inside the houses of indoor air varies ranges from 10.75 to 90 Bq m-3 and 18.65 to 210 Bq m 3, respectively. The calculated values of all dwellings of indoor radon concentration are lower than the action limit provided by ICRP. The results calculated from absorbed dose rate to lungs, equivalent dose to lungs, effective dose to specific parts of lungs tracheo-bronchial, pulmonary + pulmonary lymph region, overall lung dose due to 222Rn and 220Rn exposure, annual effective dose, excess life time cancer risk (ELCR) and lung cancer cases per year per million person (LCC) due to radon and thoron level and their risk due to exposure are also discussed. In this study, we also examined the risk effect due to radon and thoron correlated with building material and ventilation conditions.
