Vapes don’t typically get hot enough to break glycerin down into DHA. The normal temperature range is 400-450F while glycerin breaks down at 536F
That’s an invitro study which is basically worthless.
It's in cell models, not in vitro.
We'll just wait for the human data to eventually show up, but the studies running on this were killed by Trump when he killed the NIH last year. No way inhaling huge quantities of DHA isn't dangerous. This is a major concern in sunblock cremes and that's not even deep ingestion into lungs.