What is an e-cigarette?

If you saw someone puffing on an e-cigarette, you’d be forgiven for thinking they were actually smoking. The e-cigarette looks like a real cigarette and even provides a nicotine fix. However, crucially, there’s no burning tobacco, meaning no toxins such as tar, arsenic and carbon monoxide.

When someone sucks on an e-cigarette, a sensor detects the airflow and triggers a processor to turn on a heater, or ‘atomiser’. This warms up a liquid inside a replaceable cartridge, typically a solution of propylene glycol mixed with flavourings and a variable amount of liquid nicotine (some cartridges contain no nicotine whatsoever).

This creates a vapour which the user breathes in, while an LED lights up to simulate a smouldering cigarette end. The result is a device that looks, and even tastes, like a traditional cigarette, but which its advocates claim is a great deal safer.

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