WHITEWASH. “Despite some manufacturers’ claims that electronic cigarettes are harmless there is also evidence that electronic cigarettes contain toxic substances, including small amounts of formaldehyde and acetaldehyde, which are carcinogenic to humans … in some cases … contains traces of carcinogenic nitrosamines … cadmium, nickel and lead.”
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/311887/Ecigarettes_report.pdf