Social media, bright colours and fun flavours means that vaping is rapidly on the rise amongst teens. Linda Bald talks to us about the potential risks and evidence of e-cigarettes as a tool to stop smoking. Vapes contain propylene glycol or glycerin, which in itself is not harmful. But you are breathing in things that if you weren't a smokeryou could avoid. And these are all reasons put together why we don't want young people who've never smoked to use them.