Puzzle: Deadly party

A man went to a party and drank some of the punch. He then left early. Everyone else at the party who drank the punch subsequently died of poisoning. Why did the man not die?

Answer: Show answer

The poison in the punch came from the ice cubes. When the man drank the punch, the ice was fully frozen. Gradually it melted, poisoning the punch, so the people who drank it with the melted ice died of poisoning.