I don’t want to be a Redditor:
Dude, that’s a dual use item. It’s both a bathtub and a cooking pot for Bardin. As you can clearly see, the water is pitch black. Now you can decide for yourself whether that’s the cooking water left over from the troll meat in the last mission, “Hunger in the Dark”, or if it’s actually Bardin’s used bathwater from his last hygiene routine. Either way, you definitely do NOT want to get in there.
Doesn’t look like a cooking pot at all