Vape Juice Brands to Avoid: Harmful Ingredients & Worst Flavours How Zyn and other tobacco free nicotine pouches may harm your health Approximately 16,000 unique flavours have been identified for vapes, many of which appeal to potential users. Some flavours increase the toxicity of vape emissions and can generate compounds that are known to Vape Flavors and Vape Juice: What You Need to Know Johns Hopkins Medicine