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

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, 5 from borewell sources at depths ranging from 31 m to 213 m, and 5 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 UNSCEAR, USEPA and EU. Annual effective doses from ingestion and inhalation were calculated using UNSCEAR dose coefficients. The total average annual effective dose due to ingestion and inhalation for infant, children and adults ranges from 0.286 to 2.572 mSv y-1, 0.105-0.947 mSv y-1 and 0.138-1.243 mSv y-1, respectively for borewell water and 0.003-0.010 mSv y-1, 0.001-0.004 mSv y-1 and 0.002-0.005 mSv y-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 y-1 as recommended by World Health Organization (WHO, 2004) and European Council (EU, 1998). This study provides critical insight into latent radiological risks for infant, children and adults associated with mining influenced hydrogeological settings in arid zones. The elevated radon concentrations in deeper aquifers requires the need for routine monitoring and mitigation strategies, especially in water-scarce, mining-prone regions.