[rsynnott]

> The data we have shows that it was being caused by Vitamin E acetate, which was used by off-brand THC cartridges.

That's a different, less well understood respiratory problem. Some ecigarette liquid contains (or used to contain; it's banned in Europe but maybe not in the US?) diacetyl as a flavouring; that causes popcorn lung and various other problems.

Regardless, neither of these are a concern where not present, which they generally aren't.