How secondhand smoke, thirdhand smoke & vaping affects kids Vaping refers to the act of inhaling and exhaling aerosol, often called vapor, produced by an electronic cigarette or similar device. These devices heat a liquid that usually contains nicotine, flavorings, and Secondhand Vape Exposure: Effects, Who's at Risk, and More Is Second hand Vapour Harmful To Others? The Impact of E Cigarettes and Asthma: What You Need to Know Second hand vaping exposure very low compared to second hand smoking UCL News UCL University College London