Note that I don't have any save to show, but at some point in a playthrough while doing Dude's quest and getting to the part where the mutants had to be cryo-gassed it dealt unusually low damage and took some time to kill them, compared to the usual 20-40 damage it normally does. In that playthrough I visited the Ice Tower before I did Dude's quest and the damage was reminiscent of the gas damage in the Ice Tower.