[Gokiburi]

You could get run over by a truck next week - which wold make it fairly moot worrying about getting cancer ten years from now. Let's face it, life doesn't come with a warranty. Doesn't mean you have to go on a fishing trip near the outflow valves of the Fukushima plant. Doesn't mean you have to hide under your bed till doomsday either...

Sarkasm aside, you have to weigh risks vs. benefits for yourself. Gathering infromation is part of that risk assessment. Take everything the government - any government - tells you with a grain of salt. As pointed out by other posters, politics and big bidness are often intertwined in ways that aren't always beneficiary to the public as a whole, but that problem is not just limited to Japan. Bikini Atoll, La Hague, Sellafield, Three Mile Island, Chernobyl, you name it, unless you have a degree in nuclear physics and a lab full of fancy equipment you won't be able to find out if, or to what extent you're getting fed b...t by the powers that be.

Get a Geiger counter, get a dosimeter, keep in mind that there's always a certain level of natural radiation. Those two gadgets will help you to steer clear of hot spots and keep track of your personal irradiation level, but they won't tell you a thing about cancer. There's dozens of different isotopes, with varying degrees of activity, with varying carcinogenic properties.
Sorting that out could easily fill a library shelf, and it still doesn't guarantee you anything. Heck, I've known people who never touched a cigarette in their live and died of lung cancer, I also known folks who smoked like factory chimney and lived to a ripe old age...