Hammond said he’d seen something huge in the food storage, and that crew members had been turned into bloated, “poison factories”.

The people turned into a factory? Or the place was a factory. Normally a factory is a place rather than a person unless you mean metaphorically?

There were eight grotesque, swollen abominations exuding toxic gas to get rid of.

Or you could also say emitting

Isaac’s objective is to clear them out to make the air breathable again, and kill the Leviathan too.

Isaac found Hammond sitting against the wall, gasping for breathair after he’'d breathed in some toxic air on the Hydroponics deck.

Hammond said he’d seen something huge in the food storage, and that crew members had been turned into bloated, “poison factories”.

There were eight grotesque, swollen abominations exuding toxic gas that was needed to get rid of them.

Isaac’s objective is to clear them out to make the air breathable again, and kill the Leviathan too.