Studies show that many teens are unaware that vaping tools contain highly addictive nicotine and instead believe the juices are just flavorings. E-cigarettes are more popular among teens than cigarettes. They were first developed in China to help people stop smoking, but the juices contain up to 24 mg. of nicotine. New to the scene are products containing nicotine salts which contain between 40-60 mg. of nicotine.