Frozen Field

From BioShock Wiki

Frozen Field is a combat tonic which reduces cold damage received by 15%. While the wrench is equipped, it deals an extra 10 points of cold damage and has a 10% chance of freezing anyone struck. It can be stacked with Frozen Field 2.

Game Caption

Leave your foes out in the cold with Frozen Field!

Location

Looted from the corpse of Martin Finnegan in the frozen passageway to Poseidon Plaza in Fort Frolic