Are you confusing Uranium with Plutonium.
I've stood and held a Unranium fuel rod ( before it went into a reactor not after!)
Plutonium is really nasty stuff - in addition to it's radioactivity it's highly toxic micrograms can kill if it gets into you.
There are different isotopes of Plutonium 239 is 300 times more reactive than 238.
Half a pound of Plutonium was used to power the Russian mars probe that crashed in Chile in 1996.
There was about a kilo in the Viking explorers.
See here
http://en.wikipedia.org/wiki/Radioisotope_ther moelectric_generator
It depends on the particular Isotope but I'd certainly rather cautious around plut