Five cancer-causing toxins were found in the urine of 16-year-olds who inhaled e-cigarette vapor, according to a study published in the journal Pediatrics.
A second study also found that e-cigarettes encourage teens to begin smoking traditional cigarettes. Another study says that 70,000 people found that daily e-cigarette use can double the risk for heart attack.
See more at https://edition.cnn.com/2015/12/31/health/where-we-stand-now-e-cigarettes/index.html
