@michael_w_busch In my opinion that finding is not a reason for a school to change its policy. If there were a study that there was no difference in health problems between students going to schools that allow vaping and those who don't nobody would propose to drop the ban on vaping.
@ProfT
For a reason for schools to not have blanket bans on cell phones:
Some students need their phones at all times for medical reasons (examples: kids with insulin pumps or ICDs) or for accessibility (examples: hard of hearing kids with phones that pair to their hearing aids; deaf kids who use autotranscription and text-to-speech).
Even bans with exceptions can cause problems because said kids have to keep arguing for them.
And I suggest that comparing this to kids vaping is misplaced.