If it makes anyone feel any better, I've been stationed in Yokosuka most of the last 15 years (off and on, in Korea right now). Yokosuka is about 250 miles from the disaster.
My wife is on Fishing TV shows, been doing so for almost 20 years. She also writes articles on fishing and cooking saltwater fish for a national newspaper and fishing magazine. (Here's a link to one of her vids from like 98 or so). Couple others on Vimeo as well.
https://vimeo.com/82826958
Guess what? We still fish in the water and catch and eat fish. Don't know anyone who has gotten cancer yet.
There are some types of fish, especially in waters within probably 20 miles of Fukushima, like flounder and rockfish that we don't even bother going out for. Also, some of the rivers that lead into Tokyo bay have tested high for radiation, and we used to eat the clams from that area, but do no longer.
It's scary and since we can't see the radiation, don't think anyone truly knows what the exact effects will be, but for us, you'd think we would see a lot more effects as close as we are compared to someplace a few thousand miles away.
Also, one of my Navy co-workers, a NUC on lastship, got out and went to college in Tokyo. I asked him if he wasn't concerned about the radiation, and he laughed and told me the types of radiation being leaked were of not much concern. I don't remember the details.
Scary? Yes. Run for the hills time? Not so much.