If they're anything like Chernobyl, there's little effect. If they're anything like Hiroshima and Nagasaki, there's a health benefit in increased longevity and decreased incidence of disease.
Could you explain that?
If you go to
www.sepp.org and search their site using 'hormesis' or 'radiation' as search terms, you'll find several articles that address the health benefits of nuclear (and other) radiation.