It might not be related, but they've found mold inside the reactor room of Chernobyl. Apparently it's evolved a chlorophyll like molecule that captures gamma radiation. It's literally living of the energy that makes the environment lethal to almost anything else (organic or electronic).
Edit. Just checked and it's not confirmed how it's growing. They do know it grows significantly faster in a high radiation environment. They haven't pinned down the exact biological mechanism.
You're right. Also from what little I understand about radiation seems like you might want to take some more definitive action too rather than give the polonium time to finish the job. It would probably be more unpleasant than however else you were going to die
But what if they cremate you? Better be safe and also swallow some mercury zinc batteries so your corpse will explode during cremation if they go that route.