No tobacco product is harmless according to CDC scientific evidence. E cigarette aerosol that users breathe from the device and exhale can contain harmful substances including heavy metals like lead, volatile organic compounds, E cigarettes can emit formaldehyde at high levels under conditions that have been reported to be non averse to users Scientific Reports Propylne glycol : Attention aux risques et effets secondaires ! VAPES ARE FAR FROM HARMLESS. The Carnivore Bar Vaping Is Far From Harmless NOVA PBS