Just had a flashback to the stench that was created when the developer & stop bath mixed. There was a period that I developed by hand using trays in a small unventilated dark room. Later on acquired an automatic processor but the chemistry still mixed as it got old.
I still seem to have my fingers intact and my lungs don't appear to be any worse for wear.
Related; remember Itek cameras? Couldn't begin to count the number of times I was up to my armpits in chemistry pulling out jammed plate material.