Assessment of Radon Concentration and Health Hazards in Natural Spring Water of a Sub-Himalayan District

The objective of this study was to evaluate the extent of radon contamination in twenty-six drinking water samples from natural springs were collected from Dhirkot Azad Kashmir, along with four bottled mineral water samples. Radon gas escapes from the earth's crust due to uranium ores and diffuses into the atmosphere. This study assessed the levels of radon concentration, the yearly effective radiation dose, and carcinogenic risk from radon exposure in drinking water samples. The radon concentration varied from 0.28 to 30.25 Bq/L. The mean radon concentration of all samples was found to be 7.86 +/- 2.3 Bq/L. The radon concentrations in bottled drinking water were found to be lower than those in natural springs. The statistical and GIS analyses included the use of interpolation and Pearson's correlation matrix. Seven samples had radon concentration that surpassed the standard limit established by the US-EPA, which is 11 Bq/L. The average annual effective dose from inhalation and ingestion was found to be lower than the value (0.1 mSv/y) provided by the WHO, but for some natural spring water samples, it exceeded the risk limit. The cancer risk revealed that 40% of the samples had an elevated lifetime cancer risk from radon exposure. Overall, the majority of the results obtained aligned with the worldwide guidelines established by the US-EPA. However, there were a few instances where the limits were exceeded, and constant monitoring is recommended. This study establishes a baseline for radon concentration in the area and provides a basis for future studies.