Health risks
Radon - Physical, metrological and health aspects

Most radon exposure results from inhalation. Exposure to radon by ingestion is linked to its dissolution in drinking water, which can release the progeny with deposition on the stomach lining, passage through the blood and into the open air. Radon dissolved in water is easily volatile, resulting in rapid outgassing into the atmosphere.

Most radon inhaled with the air is exhaled naturally. Radon progeny aggregate on fine particles (free or attached) suspended in the air and, after inhalation, are deposited in the lungs, where they decay and emit alpha and beta radiation. Radon progeny attach preferentially to the respiratory epithelium (bronchi).