Harmful Chemicals in Vapes and E Liquids You Should Avoid SMOKO E Cigarettes They may seem sweet and tasty, but each time you vape, you breathe in harmful chemicals. One of these chemicals is diacetyl, used in popcorn flavourings for its buttery taste. When eaten, E liquids: The absence of Diacetyl as a new selling point? Vaping Post DIY E Liquid Mixing Guide: How To Make Your Own Vape Juice Vape Superstore