Yeah riiiiiight, exposure to the "minor radiation" being emitted from Fukushima is like eating a banana or getting a chest X-Ray. It's beneficial. It's good for them!
When the Navy tried to teach me about radiation safety (quite a few years ago) the running joke was "a little bit of radiation is a good thing". Hiroshima and Nagasaki survivors lived longer than the rest of the Japanese population. Which lives longer than the US population. There are other reasons for this -- obviously it's not the radiation. Hiroshima and Nagasaki survivors received more frequent heath screening and that found other problems early.
At low radiation dose levels it's somewhere between difficult and impossible to detect any sort of a significant effect. If we err, we want to err on the side of caution. But I wouldn't lose any sleep over this even if I lived in California. I certainly wouldn't charter a flight to leave Japan or buy a supply of potassium iodide for $5000 on e-bay!
ALARP, is an acronym for an important principle in exposure to radiation and other occupational health risks and stands for "As Low As Reasonably Practicable". The aim is to minimize the risk of radioactive exposure or other hazard while keeping in mind that some exposure may be acceptable in order to further the task at hand. The equivalent term ALARA, "As Low As Reasonably Achievable", is more commonly used in the United States and Canada.
48 Americans died in coal mining accidents in 2010.