n 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[1] 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,[2] while others release a flavored vapor without nicotine.[3]
The benefits and risks of electronic cigarette use are uncertain.[4][5] 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.[6][7] While they may carry a risk of addiction in those who do not already smoke,[8] there is no evidence of ongoing use among those who have never smoked.[9] They may promote continuation of addiction in those who already smoke.[10] 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.[11]
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.[12] 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.[13] The majority of users who tried e-cigarette, continue to smoke traditional cigarettes.[2] 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.[2]
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.[3][14] 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.[15]