There's plenty of knowledge about the effects of nitrogen from it being a workplace hazard in a lot of places.
One example is anchor chain lockers on ships. That big iron chain that just came out of the salt water wants to turn into iron oxide so it absorbs all the oxygen making the environment extremely nitrogen rich. In several cases people have been climbing down into it and without warning go unconscious. I think one case had three dead at the bottom before the fourth guy comes along with some brains and thinks maybe I shouldn't go down there.