Depleted Uranium

The sub-micron particles blow about the world in the wind.
Previously, the US had an annual lung cancer incidence of 175000.
This year, 2006, that figure was reached in the first two months.
In my opinion the increase is a direct result of the worldwide use of DU.
The whole world is being poisoned, not just the bombed region.

4.468 billion years — half-life of uranium-238
-Quote from Wikipedia.

Here's another:
4.5 billion years — age of the Earth

And another:
10 billion years — expected main sequence lifetime of a G2 dwarf star (like the Sun)

You see, the Sun will die before half of this stuff is gone.