Radon Levels in Water Sources From Mining Zones of Jodhpur and Nagaur, Rajasthan: Implications for Radiological Health Risk and Environmental Safety

Abstract This study aimed to evaluate the concentration of 222Rn in drinking water from mining-impacted regions of Jodhpur and Nagaur districts in Rajasthan, India by RAD7 detector with RAD H2O accessory. A total of 200 water samples were systematically collected from 20 sites, five from borewell sources at depths ranging from 31 m to 213 m, and five from tap/storage. Our findings indicated that groundwater samples exhibited higher radon levels compared to surface-stored tap water, with values in deep aquifers exceeding the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2008), U.S. Environmental Protection Agency (USEPA, 1999), and European Commission (EU, 2001). Annual effective doses (AEDs) from ingestion and inhalation were calculated using UNSCEAR dose coefficients. The total average annual effective dose due to ingestion and inhalation for infants, children, and adults ranges from 0.286 to 2.572 mSv yr−1, 0.105 to 0.947 mSv yr−1, and 0.138 to 1.243 mSv yr−1, respectively, for borewell water and 0.003 to 0.010 mSv yr−1, 0.001 to 0.004 mSv yr−1, and 0.002 to 0.005 mSv yr−1, respectively, for tap water samples. The total average annual effective dose from all the borewell water samples has been found higher than 0.1 mSv yr−1 as recommended by World Health Organization (WHO, 2004) and European Commission (EU, 1998). This study provides critical insight into latent radiological risks for infants, children, and adults associated with mining influenced hydrogeological settings in arid zones. The elevated radon concentrations in deeper aquifers require the need for routine monitoring and mitigation strategies, especially in water-scarce, mining-prone regions.