The projections of thousands of late cancer deaths based on LNT, are in conflict with observations that in comparison with general population of Russia, a 15% to 30% deficit of solid cancer mortality was found among the Russian emergency workers, and a 5% deficit solid cancer incidence among the population of most contaminated areas.
Observations on the Chernobyl Disaster and LNT. (thanks Peter for pointing it out)
LNT stands for "Linear Non-Threshold" hypothesis that postulates that no matter how low level of radiation, its harmful effects accumulate and add up over time.
This and other papers posted in this blog ( Gamma radiation protects against cancer, in low doses seems to indicate that this theory is dead.