[verylittlemeat]

If you vape also consider making the liquid yourself. The base is just 2 ingredients and you can carefully source your flavoring agents. Making your own can be 50-100x cheaper than buying premade.

But as other people here said - diacetyl / popcorn lung has been known on the popular vaping scene for almost a decade now. Not to speak in absolute terms but I think it would be hard to find a retailer these days that carries any liquid with diacetyl in it.