You know as I think about it, perhaps the filler in the cartomizers has something in them that is causing / aggitating it. I've been having a hell of a time getting my echo cartomizers to not burn up after the first day or two using them (and I mean burning holes in the filler too). My supplier basically told me it was unheard of and that his lasts for months with no problem, and offered me 2 free ones with another purchase of 4 more. Awesome that solves nothing but make me spend more money, thanks! Those six are doing better but after 3 days two are going bad. Anyways my point is, burning filler entering my lungs can't be healthy right? I don't know about Tracy's situation but if there's some chemical in the filler then it's hitting the atty at some point by the juice carrying it or the atty burning the filler. I'm going to vape my regular mix because I know that shouldn't cause me illness, and if I get worse or not better, then I'll have the carto filler to investigate, and if I get better I'll stick to my belief it's the VG. I've never vaped over 20% VG before and that Astro Bacco is 70% VG.
I've heard of several having VG allergies, but there are all kinds of flavors - any one of which you might be allergic to. Take one of the carts you were going to throw away and vape some 100 % VG - no flavor - no nic - and see what happens. That would at least help you to narrow things down. If you have no reaction to the 100% VG, you'll know to look elsewhere. I'm sorry to hear about folks having problems.