Vaping is harmful in 3 ways: 1.) To the user, as harmful ingredients are not disclosed. 2.) To others, as vape clouds contain cancerous chemicals, heavy metals, and nicotine, which can be Does Vape Smoke Stick to Walls? Velvet Cloud Do Nicotine Vape Pens Smell? Even after a cigarette is extinguished, nicotine and other chemicals react with indoor pollutants to form a hazardous film known as thirdhand smoke. This residue re emits harmful gases back into the environment.