Radon-222 and Leukemia

Leukemia was the first medically observed human cancer related to ionizing radiation in the 1945 follow-up study of atomic bomb survivors. The bone exposure and dose calculated here are based on the measured solubility of the noble gas Rn-222 in blood. A fraction of the Rn-222 gas in blood distributes as dissolved gas to all organs, with the fraction depending upon the blood flow rate to the organ. The exposure and dose calculated are for men and women based on measurements made for the blood flow rate to the femur, the largest bone in the human skeleton. The annual exposure and dose estimated for continuous Rn-222 inhalation of 100 Bq m(-3) are very low and unlikely to cause leukemia. Other neurological issues, from lifetime exposure to low activity concentrations of Rn-222 alpha particle exposure in bone, are unknown.