Part of the reason people react so strongly to any hint of radiation in the environment is a lack of knowledge about how widespread radiation is in the natural world, along with an inability to comprehend dose numbers. Another factor is the persistence of the outdated concept that any increase in exposure equates to increased risk of negative health effects, aka the linear no-threshold (LNT) model
http://en.wikipedia.org/wiki/Linear_no-threshold_model. This model has been in trouble for some time as evidence accumulates in favor of the more nuanced and evidence based theory
of radiation hormesis
http://www.radpro.com/641luckey.pdf. According to this theory, low doses of radiation exposure in excess of normal background levels exerts a number of stimulative and reparative effects at a cellular level that act to improve health. This is supported by large amounts of research evidence, but has been slow to find favor with regulators, resulting in the continued existence of safety standards for public exposure that are excessive. Better recognition of the evidence for radiation hormesis would help to reduce public apprehensions about nuclear energy.
