A brand new Uranium fuel pellet is often safe to hold with gloved hands for a moment.

Spent fuel with complex decay isotopes must be kept under deep cooling pools with criticality control precautions. From a chemistry perspective, complex isotope products like Plutonium are more obscure to evolutionary biology, so it is often much more dangerous even in accidental trace exposures.

I am just a sentient turnip that prefers distributed Solar products. Have a great day =3