Vaping is both idiotic and dangerous. I know a friend who caught his son vaping, it took them two hours to get the film off the inside of the windows, the stuff was like goo. They can and do put all kinds of chemicals in the vape, just terrible. I’m all for making it illegal, it’s doing drugs, period.
So I am reading my Vape liquid and FYI, here are the ingredients. USP Certified propylene glycol ( if you eat ice cream you eat PG), USP Grade vegetable glycol (used in too many foods to list), USP Grade nicotine (can be adjusted to ones needs), natural and artificial flavoring (once again, in just about every food). It is reckless to discourage smokers to not vape.
Don’t know what your friend was using but my windows are immaculate. I only purchase my vape products from top of the line retailers. The best is VAPOR-FI, which can be found on line and there are many stores around the country.