Try a different source of VG for a while and if the lung issue goes away then go back to the local VG you bought and see if the lung issue comes back.
Side note: USP means very little when buying small quantities of VG unfortunately. All these smaller internet companies who sell "UPS" VG in smaller quantities of, say, less than 5-gallon pail, are rebottling it. Nothing wrong with that but if you repackage a USP product it has to be done under USP standards of cleanliness in order for the rebottled product to maintain it's USP grade.
So as an example, while lots of people here on ECF love Bulk Apothecary and think it's USP grade because BA says it is, I have reason to believe that it isn't because I contacted them. First, I merely asked them if their VG sold in smaller quantities is rebottled by them. The first response was no. But then another department replied to the email and said the CS agent was mistaken and that the smaller quantities are rebottled by them.
I already knew this since, being a smaller company, the price for the smaller bottles would be a lot higher if they were buying them wholesale from an actual USP facility. You have to
buy drums and rebottle it to have a competitive price as a smaller company. I just wanted to hear it from their mouths so as to set them up for the million dollar question, which is: are you rebottling under USP guidelines? If so, can I see documentation?
Their response was a run-around answer. They said they would get back to me and never did. This is irresponsible of them since I could be using it for an application that absolutely requires true USP grade VG. Nonetheless, they blew me off. For all they knew I was a company doing a test order and would have been a customer that was going to later
buy 55 gallon drums on subsequent orders, but they chose to ignore me and lose a potential profitable customer. That tells me there is a great chance their rebottled USP VG isn't technically USP so they didn't want to reveal that.
As I understand it, the US govt doesn't regulate USP products so you can get away with repackaging a USP product under conditions not clean enough by USP standards and legally get away with calling the repackaged product "USP" merely because the larger USP package you rebottled from is actually USP grade.
I'd bet that 90% or more of smaller internet companies selling self-rebottled USP VG is not actually USP grade after the rebottling is done. I'd trust that Tractor Supply's gallons of VG as actual true USP grade before any of the small internet companies claiming USP grade VG.
You should try to research the source of that VG you bought locally to see if you can surmise if it was truly bottled or rebottled under USP guidelines.
