A collaborative research by scientists of Kerala University and Bhabha Atomic Research Centre (BARC), Mumbai, has shed light on the hydrological applications of radon, a radioactive noble gas.
Professor Sabu Joseph and S. Sukanya, a guest faculty, of the Department of Environmental Sciences, Kerala University; and Jacob Noble of the Isotope and Radiation Application Division at BARC have highlighted findings on radon behaviour in hydrological systems in a study published in the peer-reviewed journal Chemosphere.
Known to be the second leading cause of lung cancer after tobacco, the naturally-occurring gas is formed after the decay of uranium in the earth’s crust and enters the environment through the soil. While it is also ubiquitously present in groundwater and surface water, dissolved radon enters the indoor air through the water drawn from wells.
Short half-life
Despite posing no immediate threat due to its short half-life (the time required for one-half of the atomic nuclei of a radioactive sample to decay) of 3.8 days, the solid polonium isotopes of radon, however, can get lodged deep within the lungs when inhaled.
According to Prof. Joseph, a World Health Organisation (WHO) study has indicated that the likelihood of radon causing lung cancer is significantly higher in individuals who smoke. Besides, the United States Environmental Protection Agency estimates that radon contributes to approximately 21,000 lung cancer deaths each year.
“However, beyond its health implications, radon has been an invaluable asset in unravelling the mysteries of hydrological systems and opens up new avenues for water resources management,” he said.
The gas serves as a powerful tool for tracing surface water-ground water interactions in river basins, investigating submarine groundwater discharge and conducting water budgeting studies. Radon also finds relevance in geochemical explorations by aiding the detection of non-aqueous phase liquids (NAPL) contamination in ground water and thereby, facilitating the development of strategies to protect water resources.
A book on Environmental Radon co-authored by Prof. Joseph and Dr. Sukanya also emphasises on the potential applications of radon for hydrological investigations.
