An electronic cigarette is an electronic device that simulates tobacco smoking. It consists of an atomizer, a power source such as a battery, and a container such as a cartridge or tank. Instead of smoke, the user inhales vapor. As such, using an e-cigarette is often called "vaping".The atomizer is a heating element that atomizes a liquid solution called e-liquid. E-cigarettes are activated by taking a puff or pressing a button. Some look like traditional cigarettes, and most versions are reusable.
E-cigarettes create an aerosol, often called vapor, made of particulate matter. The vapor typically contains propylene glycol, glycerin, nicotine, flavors, and traces of nitrosami nes,other toxicants, carcinogens, heavy metals, and metal nanoparticles. Its exact composition varies, and depends on several things including user behavior.
The health effects of vaping are not clear but vaping is likely less harmful than smoking tobacco. E-cigarette vapor contains fewer toxins, in lower amounts, than cigarette smoke. E-cigarette vapor does also contain harmful chemicals not found in tobacco smoke. The World Health Organization's position is that it is hard to say if vaping is safer than smoking and it is best to not use nicotine at all.
Nicotine is harmful and highly addictive. E-cigarettes can lead to tobacco smoking, and can be more addictive than tobacco. For people trying to quit smoking with medical help, e-cigarettes have a higher quit rate than normal nicotine replacement therapy. For most use, e-cigarettes do not raise quit rates.
An electronic cigarette consists of an atomizer, a power source such as a battery, and a container for the e-liquid such as a cartridge or tank.
E-cigarettes have evolved over time, and the different designs are classified in generations. First-generation e-cigarettes, which tend to look like traditional cigarettes, are called "cigalikes". Second-generation devices are larger and look less like traditional cigarettes. Third-generation devices include mechanical mods and variable voltage devices. The fourth-generation includes sub-ohm tanks (meaning that they have electrical resistance of less than 1 ohm) and temperature control devices.There are also pod mod devices that use protonated nicotine, rather than free-base nicotine found in earlier generations, providing higher nicotine yields through the production of aerosolized protonated nicotine.
E-liquid is the mixture used in vapor products such as e-cigarettes. E-liquid formulations vary widely. A typical e-liquid comprises propylene glycol and glycerin (95%), and flavorings, nicotine, and other additives (5%). The flavorings may be natural, artificial, or organic. Over 80 chemicals such as formaldehyde and metallic nanoparticles have been found in the e-liquid. There are many e-liquid manufacturers, and more than 15,000 flavors.
In the US, under Food and Drug Administration (FDA) rules, e-liquids must comply with manufacturing standards. Industry standards are published by the American E-liquid Manufacturing Standards Association (AEMSA). EU standards are in the EU Tobacco Products Directive.
Since their entrance to the market around 2003, e-cigarette use has risen rapidly. In 2011 there were about 7 million adult e-cigarette users globally, rising to 68 million in 2020 compared with 1.1 billion cigarette smokers.
E-cigarette use is highest in China, the US, and Europe, with China having the most e-cigarette users. The rise was thought to be due to targeted marketing, their lower cost compared to tobacco, and belief that e-cigarettes are safer than tobacco.
There are varied reasons for e-cigarette use. Most users are trying to quit smoking, but a large proportion of use is recreational or as a way to get around smoke-free laws. Many people who use e-cigarettes still smoke, raising concern that they may be delaying or deterring quitting. Some people say they want to quit smoking by vaping, but others vape to circumvent smoke-free laws and policies, or to cut back on cigarette smoking. Many people vape because they believe vaping is safer than smoking.
Concerns over avoiding stains on teeth or odor from smoke on clothes in some cases prompted interest in or use of e-cigarettes. Some e-cigarettes appeal considerably to people curious in technology who want to customize their devices. There appears to be a hereditary component to tobacco use, which probably plays a part in transitioning of e-cigarette use from experimentation to routine use.
Many users say they like the choice of flavors and comparatively low price of e-cigarettes compared to cigarettes.
In the context of drugs, the gateway hypothesis is that using less harmful drugs can lead to more harmful ones. There is good evidence that vaping is a "gateway" to smoking as well as an "exit ramp" from smoking. Mentally ill people, who as a group are more susceptible to nicotine addiction, are at particularly high risk of this.
Worldwide, increasing numbers of young people are vaping. With access to e-cigarettes, young people's tobacco use has dropped by about 75%.
Most young e-cigarette users have never smoked, but there is a substantial minority who both vape and smoke. Young people who would not smoke are vaping. Twice as many young people vaped in 2014 than also used traditional cigarettes. Young people who smoke tobacco or marijuana, or who drink alcohol, are much more likely to vape. Among young people who have tried vaping, most used a flavored product the first time.
Most young people are not vaping to help them quit tobacco. Vaping correlates with smoking among young people, even in those who would otherwise be unlikely to smoke. Experimenting with vaping encourages young people to continue smoking. A 2015 study found minors had little resistance to buying e-cigarettes online. Teenagers may not admit using e-cigarettes, but use, for instance, a hookah pen. As a result, self-reporting may be lower in surveys.
The "catalyst model" suggests that vaping may proliferate smoking in minors by sensitizing minors to nicotine with the use of a type of nicotine that is more pleasing and without the negative attributes of regular cigarettes. A 2016 review, based on the catalyst model, "indicate that the perceived health risks, specific product characteristics (such as taste, price, and inconspicuous use), and higher levels of acceptance among peers and others potentially make e-cigarettes initially more attractive to adolescents than tobacco cigarettes. Later, increasing familiarity with nicotine could lead to the reevaluation of both electronic and tobacco cigarettes and subsequently to a potential transition to tobacco smoking
Health effects
The benefits and the health risks of e-cigarettes are uncertain, including their long-term effects. There is tentative evidence they may help people quit smoking. Pods contain different doses of nicotine, and these levels are regulated in some countries. Following the possibility of nicotine addiction from e-cigarette use, there is concern children and young people may start smoking cigarettes. Their part in tobacco harm reduction is unclear, while another review found they appear to have the potential to lower tobacco-related death and disease. Regulated US Food and Drug Administration (US FDA) nicotine replacement products may be safer than e-cigarettes, but e-cigarettes are generally seen as safer than combusted tobacco products.The risk of early death may be similar to that of smokeless tobacco. The risk of serious adverse events was reported in 2016 to be low. Less serious adverse effects include abdominal pain, headache, blurry vision, throat and mouth irritation, vomiting, nausea, and coughing. Nicotine is harmful. In 2019 and 2020, an outbreak of severe vaping lung illness in the US was strongly linked to vitamin E acetate by the CDC. E-cigarettes produce similarly high levels of particulates in the air as do tobacco-cigarettes. There is "only limited evidence showing adverse respiratory and cardiovascular effects in humans", with the authors of a 2020 review calling for more long-term studies on the subject. A 2020 review found e-cigarettes increase the risk of asthma by 40% and chronic obstructive pulmonary disease by 50%.
Pregnancy
The Royal College of Midwives states, "While vaping devices such as electronic cigarettes (e-cigs) do contain some toxins, they are at far lower levels than found in tobacco smoke. If a pregnant woman who has been smoking chooses to use an e-cig and it helps her to quit smoking and stay smokefree, she should be supported to do so." Based on the available evidence on e-cigarette safety, there was also "no reason to believe that use of an e-cig has any adverse effect on breastfeeding." The statement went on to say, "vaping should continue, if it is helpful to quitting smoking and staying smokefree". The UK National Health Service says: "If using an e-cigarette helps you to stop smoking, it is much safer for you and your baby than continuing to smoke.".Many women who vape continue to do so during pregnancy because of the perceived safety of e-cigarettes compared to tobacco.
