Natural radioactivity is mainly something that hits you from the 'outside' there is a rock or even the bricks of your house that emits something ... it hits your skin.
The exception of course is Radon, a gas produced by decay and radioactive itself. So houses build of particular bricks emit Radon, you inhale it, so it is inside of you. But also Radon easy escapes from the building, it is not building up a concentration.
Here we are talking about stuff that is getting inside of your body, and there it will kill you.
Your body is full of potassium-40, carbon-14, thorium, uranium and their decay products. If you're so scared of radioactivity that you must demand Cs-137 to decay to one-millionth of the current concentrations before you feel safe, then go commit suicide. There is no place in the solar system that will satisfy your demands. You, sir, are a lunatic.
The lunatic is you, as you have no clue.
First of all a healthy person has no Uranium or Thorium in his body.
Second, you are again mixing up external radiation by natural sources with radioactive elements incorporated into the body, you simply have no clue how to distinguish one from the other. So you don't qualify for this discussion.
Beyond me is why you claim such nonsense: This means that it will be dispersed in the environment at a much greater rate than it will be concentrated in humans. In fact, it is not even detectable around Fukushima Daiichi.
Sorry, you are an idiot and troll, should delete the rest of my post, as that claim of yours nails it.
The current evacuation zone is something like 40km around the plant. The actual contaminated area is a stripe going for 300km north east from the plant covering Osaka, Tokyo etc.
The fallout is measurable every where in north Japan. You are simply a complete idiot, good day moron!