Exactly the type of thing I was curious about!

I've actually practiced going into such environments a little bit through work, and it's part of what makes me curious. I wonder how long our bodies could tolerate it. It would be interesting if oxygen through the lungs was enough on a long-term basis!

This is part of what made me curious about it! Maybe there is a long-term benefit or cause of detriment to only the lungs having access to oxygen?