Enhanced frequency of micronuclei in lymphocytes from current as opposed to former uranium miners

For current miners there is a significant correlation between micronucleus frequency and effective dose received over the last 12 months. The dose at which a doubling of the micronucleus frequency is observed is around 10 mSv. This is a much smaller dose than would usually be expected to be detectable with this test, and raises a number of questions about the induction of micronuclei by alpha radiation from radon and its decay products.