e-cigarette

An e-cigarette is a battery-powered device that heats a liquid into an aerosol the user inhales — a process commonly called vaping. Rather than burning tobacco, it warms a solution usually containing nicotine, propylene glycol or vegetable glycerine, and flavourings, producing a visible mist without the combustion smoke of a cigarette.

Because there is no burning, the aerosol lacks tar and many of the combustion products of cigarette smoke, which has led some to view vaping as less harmful than smoking. However, the aerosol is not harmless water vapour: it still delivers nicotine (highly addictive) and exposes the airways to fine particles, flavouring chemicals, heavy metals from the heating coil, and oxidants whose long-term lung effects are not fully known.

Evidence on e-cigarettes is genuinely mixed and evolving. For an established adult smoker, switching completely to vaping is likely less harmful than continuing to smoke and can aid quitting, though it is not risk-free and the goal is to stop both. For young people and never-smokers, by contrast, vaping carries real risks — nicotine addiction, possible airway irritation, and a gateway toward smoking — with no benefit. Because the devices are recent, conclusions about decades-long lung outcomes remain provisional.