Nicotine, propylene glycol, sweet flavorings, and various toxic chemicals like carcinogens and heavy metals are found in vape juice, posing health risks, especially to youth. Does Vape Liquid Expire? Shelf Life, Storage, and Safety Explained Vaping Is Far From Harmless NOVA PBS Do you know what you're vaping? Propylene glycol (PG) and vegetable glycerin (VG) are the main liquids in vapes. When heated, these chemicals turn toxic and aren't safe to breathe. What You Need to Know About Propylene Glycol My Vapery UK HOW TO TALK TO YOUR KIDS ABOUT VAPING