I believe that toxicity would only be achieved if it were turned into a microfine powder and divided among humans to inhale, eventually killing all by lung cancer.
In solution or as a coarse powder, its toxicity to man is about the same as caffeine.
I still would not pick up that rock up.
Your first sentence is true. Kinda like anthrax.....you have to make it very fine and disperse it. Plutonium is heavy so most particles will fall on the ground
Nader has famously pronounced that one pound of plutonium released into the environment would end life on earth. (Soviets tried this experiment in 1986 at Chernobyl. If life on earth has ended, hiding this fact is the KGB’s most successful disinformation effort ever.)
Nader's pronouncement was based on research which showed that one pound of plutonium as an aspirate contains two million lethal doses, for humans. The population of the earth at that time was around two billion people, so he borrowed a “b” from the type font and made two million into two billion and with typical left wing solipsism generalized “human life” into “life” and changed “could if applied as an aspirate into the lungs of each individual result in the deaths of most to them” to “would end life”.
It would, of course, be unfair to call Nader an alarmist.