That much plutonium, and he should have been dead right there.
It doesn’t take much. But then I suspect it hasn’t been studied to closely.
Plutonium 239 is an alpha particle emitter (helium nuclei)Your skin stops it. The major problem is breathing in plutonium dust, which affects the lungs, which tissues are sensitive to alpha particles, which can occur if you don’t follow safety procedures. Another difficulty is alpha emitters on things like cigarettes which are sucked into the lungs.