"For the near future, what all that means, in effect, is that the world has to accept chronic radiation releases from Fukushima as the price for avoiding another catastrophic release. And even then, it's not a sure thing.
But there's another aspect of Fukushima Unit #3 that's even less reassuring. Unit #3 is the one Fukushima reactor that was running on Mixed oxide fuel, or MOX fuel , in its fuel rods. MOX fuel typically uses Plutonium mixed with one or more forms of Uranium. Using Plutonium in fuel rods adds to their toxicity in the event of a meltdown. In part because Plutonium-239 has a half-life of 240,000 years and can be used to make nuclear weapons of "dirty bombs," its use in commercial reactors remains both limited and controversial . Because it contains Plutonium, MOX fuel is more toxic than other nuclear fuel and will burn at lower temperatures."