Yeah I figured any glass dust traveling down the tube would just stay in the water but we still handle slides and stems plenty so if there is any on the joints then that means its being transferred to everything we touch including face/eyes/nose/mouth.
I tried taking his advice and googling "glass dust lawsuits" but a quick search didn't really turn up anything.
I'm going to go do the tape around the joint experiment and see if I get any glass dust.