Interesting article about Manhattan Project scientists contaminated by Plutonium.
The Scientists Who Pee Plutonium
Government conducted live-long study of the 26 contaminated people. Results, quote: "the mortality rate for the group is about 50 per cent lower than the national average."
It appears that up to a certain level of radiation, its effects don't seem to be harmful and it is possible (though not proven) that it may even be beneficial. See also the other posts on the subject.
It may be a surprise to learn that the members of the UPPU club have all done well, especially when compared to national averages. “They’ve fared pretty well as a group,” George Volez and expert on plutonium exposure told Los Alamos Science in 1995. “Of the original 26, only seven have died, and the last death was in 1990.