According to the new laboratory study from the US, flavourings used in electronic cigarettes can intensify the toxicity of the vapour inhaled by a user. Moreover, electronic cigarette vapour becomes more toxic when users upgrade their devices increasing the voltage of battery output.
Senior researcher Maciej Goniewich, an assistant professor of oncology at Roswell Park Cancer Institute in Buffalo, N. Y., says that the toxins in e-cigarette vapour irritate and inflame cells in the respiratory tracts and can cause or exacerbate breathing issues in some users.
Researchers suggest that their findings raise some concerns about safety of flavourings used in electronic cigarettes.
More information here.