An electronic cigarette (e-cig or e-cigarette), personal vaporizer (PV) or electronic nicotine delivery system (ENDS) is a battery-powered vaporizer which simulates tobacco smoking by producing an aerosol that resembles smoke. It generally uses a heating element known as an atomizer, that vaporizes a liquid solution known as e-liquid. E-liquids usually contain a mixture of propylene glycol, vegetable glycerin, nicotine, and flavorings, while others release a flavored vapor without nicotine.
The benefits and risks of electronic cigarette use are uncertain. Some evidence suggests e-cigarettes may be safer than smoking tobacco products, and possibly as safe as other nicotine replacement products but there is insufficient data to draw conclusions. While they may carry a risk of addiction in those who do not already smoke, there is no evidence of ongoing use among those who have never smoked. They may promote continuation of addiction in those who already smoke. With the spread of e-cigarette use, calls to poison control centers related to possible ingestion or skin exposure to e-cigarette liquids have increased.
The frequency of use has increased with up to 10% of American high school students having ever used them as of 2012 and around 3.4% of American adults as of 2011. In the UK the number of e-cigarette users has increased from 700,000 in 2012 to 2.1 million in 2013. About 60% are smokers and the most of the rest are ex-smokers. The majority of users who tried e-cigarette, continue to smoke traditional cigarettes. Currently marketed e-cigarette devices arose from an invention made in China in 2003 and devices are predominantly manufactured in China. E-cigarette brands have been rapidly expanding using aggressive marketing campaigns similar to those used to popularize cigarettes in the 1950s and 1960s.
Because of the possible relationship to tobacco laws and medical drug policies, electronic cigarette legislation and public health investigations are currently pending and are being debated in many countries. The European Parliament passed regulations in February 2014 requiring standardization of liquids and personal vaporizers, disclosure of ingredients, and child- and tamper-proofing of liquid containers; the Food and Drug Administration published proposed regulations in April 2014 along similar lines.