Since radon emits alpha when it decays, cant it also present a lung cancer risk?
Technically, there is some risk of increased lung cancer risk from breathing radon. However, the probability of a radon atom decaying at the instant it passes through the lungs and into the blood and back out (by the normal gas exchange process) is very low compared to the chances of a radon decay product decaying while in the lungs, since the radon decay products stick and accumulate in the lungs. The other factor is that radon has a much longer half-life of 3.8-days compared to Polonium 218 at 3.05 minutes and Polonium 214 at 164 micro-seconds, which means these short-lived radon decay products will likely breakdown and release radiation before your lungs can clear them.
