>>10930137i think they're about equal, actually, at least on an acute exposure level. botulotoxin's 1.3 ng/kg is in the same ballpark as what figures i can find for po210, with an LD50 of something like 90 nanograms
obviously polonium's worse if you factor in long-term radiation damage from a non-lethal dose but i think that's a different thing than OP is asking
