Turn down the heat
Researchers at Portland State University have published research (Jan 22nd 2015 New England Journal of Medicine) showing that the level of Formaldehyde (a known carcinogen) is 5 to 15 times higher in the vapour of e cigarettes as it is in normal tobacco cigarettes. Originally, e cigarettes were not supposed to generate high temperatures and were thus thought to restrict inhalation of any toxic chemicals, but newer models allow people to ‘turn up the heat’.
David H. Peyton, PSU chemistry professor and lead researcher stated, "Our research shows that when heated at higher temperatures, e-cigarette juices can vaporize and form large amounts of ‘hidden formaldehyde,’ five to 15 times higher than the amount of formaldehyde in traditional cigarettes.”
Formaldehyde is a known human carcinogen. It is a colorless, strong-smelling gas, commonly used as an adhesive in building materials such as particle board and in mortuaries as an embalming fluid. Formaldehyde is also used as an industrial fungicide, germicide and disinfectant.
E-cigarette devices and their liquids are not regulated by the Food and Drug Administration (FDA). A lack of regulation means that companies are not required to disclose their manufacturing process, their ingredient list or any scientific data to the FDA.
Ref: https://www.pdx.edu/news/psu-researchers-uncover-high-levels-hidden-formaldehyde-e-cigarette-vapor