Significant amounts of toxic metals, including lead, leak from some e-cigarette heating coils and are present in the aerosols inhaled by users, according to a study from scientists at Johns Hopkins Bloomberg School of Public Health.
https://www.facebook.com/ScienceNaturePage/videos/1399621006836820/
https://ehp.niehs.nih.gov/ehp2175/
https://www.sciencedaily.com/releases/2018/02/180221152347.htm