Electronic cigarettes, or e-cigarettes, are cigarette-shaped devices that deliver nicotine-laced vapor when the user inhales (called vaping). Some e-cigarettes look like traditional tobacco cigarettes, but many newer devices do not. An e-cigarette has a mouthpiece with an air-activated sensor that uses a battery to power a heating element. The heat vaporizes liquid nicotine or other substances contained in a small, replaceable cartridge. In most cases, a terminal end lights when the heating element activates, mimicking the glow from the end of a cigarette or cigar.
Background and scientific foundations
Herbert A. Gilbert invented the first electronic cigarette and had it patented in the United States in 1965. However, aerosolized electronic cigarettes were first developed in China in 2003 by Hon Lik of Ruyan Technology and patented internationally in 2007. By 2008, Ruyan reported annual sales of 300,000 e-cigarettes. Since then, e-cigarettes have diversified in terms of size, shape, and flavors of nicotine and other substances used. According to a report by the American Heart Association, "there were 466 brands and 7764 unique flavors of e-cigarette products" by 2014.
Electronic nicotine delivery systems (ENDS) are the most common way for young people to use tobacco. Numerous names are associated with ENDS, including cig-a-likes, e-cigarettes, e-cigs, e-cigars, e-hookahs, electronic cigars, mods, tank systems, vape pens, and vapes. The basic components of an ENDS consist of a battery, an atomizer with a heating element, and a cartridge containing an e-liquid. The battery is activated when the user inhales (with an automatic unit) or presses a button (with a manual unit). The battery triggers the heating element of the atomizer. The heat turns the liquid to a fine mist or vapor that is then inhaled by the user.
Vaping cartridges contain e-liquid—a mixture of propylene glycol, glycerin, and additives like nicotine and flavorings. Usually, the added nicotine is a liquefied synthetic. Propylene glycol is an organic chemical compound. It is sweet tasting, yet it is virtually odorless. It produces a visible smoke that is often used for film, television, and stage productions where actual smoking is prohibited due to health and fire safety restrictions.
A typical canister holds up to 3 milliliters of liquid. The added nicotine concentrations range from none to 24 milligrams per milliliter. In comparison, a traditional cigarette normally contains 8 to 20 milligrams of nicotine. An e-cigarette may contain up to 72 milligrams of nicotine.
Psychologically, the electronic cigarette experience mimics many of the same behaviors and sensations of actual smoking. The user feels a puff of warm gas as the vaporized propylene glycol produces a small puff of vapor or smoke. Unlike smoke from cigarettes, e-cigarette vapor does not contain particulate matter from combustion. So, the puff of vapor quickly diffuses and dissipates. However, some studies show that users' lungs are exposed to chemicals and toxins during the heating and vaporizing process. Some of these inhalants include cadmium, chromium, and nickel. They can also include other microscopic particles of metal coming from the atomizing device itself. Other studies show that e-cigarettes are a useful aid for those who wish to stop smoking tobacco.
Impact on health
Usage worldwide has soared, often in populations too young to legally use tobacco products. According to the Centers for Disease Control and Prevention (CDC), e-cigarettes comprised less than two percent of all tobacco-related sales in the United States in 2010. Since that time, use has increased rapidly and dramatically. In 2017, the CDC reported that "2.8 percent of U.S. adults were current e-cigarette users."
Critics warn that the danger of e-cigarettes lies in the high dose of nicotine available through the device. In addition to inhalation toxicity, nicotine is easily absorbed through the skin. Because of this, the handling of used or damaged cartridges is also a mechanism for excess nicotine exposure. Nicotine, even in synthetic form, is highly toxic. E-cigarettes usually contain much higher amounts of nicotine than traditional cigarettes.
Usage among children and young adults
Both the CDC and the Food and Drug Administration (FDA) estimated that more than three million American middle and high school students used e-cigarettes in 2015, an increase from 2.36 million users estimated in 2014. In response to government surveys, 16 percent of high school students and 5.3 percent of middle school students said they were current users of e-cigarettes, making ENDS the most common way young people use tobacco. By 2019, the number of middle and high school students had increased to more than five million—nearly one million claimed they used e-cigs on a daily basis.
With increased vaping in the United States came an increase in adverse consequences. Vaping especially presents an increasing hazard for small children. By 2014, more than 40 percent of calls to poison control centers in the United States—half of which involved children less than five years of age—related to e-cigarette use. Health officials argued that flavorings made the e-cigarettes more attractive to small children. Delivered in such a concentrated form, a single puff on an e-cigarette can induce vomiting in a small child. With sufficient exposure, nicotine can cause muscle paralysis and death in small children.
Discussions on banning the flavorings in the United States continued for several years. A November 2019 report by the Vapor Technology Association, estimated that a flavor ban could result in a loss of 150,000 jobs and $8.4 billion in sales. Regardless, in December 2019, US President Donald J. Trump (1946–) signed an amendment to the Federal Food, Drug, and Cosmetic Act, raising the legal age to buy tobacco products from 18 to 21 years of age; the amendment includes ENDS. In January 2020, the FDA issued an enforcement policy on unauthorized flavored cartridge-based ENDS products, including mint and fruit, because the flavoring appeals to children and young adults. Hoping to curb the use of ENDS among young people, the ban went into effect in February 2020.
E-cigarette or vaping associated lung injury (EVALI)
ENDS are used for vaping substances other than nicotine, including tetrahydrocannabinol (THC), the main psychoactive compound in marijuana. Oftentimes, vitamin E acetate is utilized as an additive in THC products. Normally, vitamin E acetate is used topically in cosmetics or ingested as food or a dietary supplement. However, when it is inhaled, vitamin E acetate interferes with normal lung functioning. This can cause a condition known as e-cigarette or vaping associated lung injury (EVALI).
In 2019, vitamin E acetate was linked to an outbreak of EVALI in the United States. Several cases occurred early in the year, but by late summer, the flare-up peaked. According to the CDC, in February 2020, more than 2,800 people had acquired EVALI in the United States, Puerto Rico, and the US Virgin Islands, resulting in 68 deaths. The median age of those who died was 49, ranging from 15 to 75. The CDC reported that half (50 percent) of the EVALI cases were associated with people using ENDS with THC.
Issues and developments
There is an ongoing public health debate about the long-term impacts of electronic cigarette use. Some studies show that they offer the promise of a physiologically less-harmful alternative to traditional tobacco smoking, including the elimination of carcinogenic tars. Other public health experts counter that vaping is a portal for teens and other users to start smoking.
The World Health Organization (WHO) recommends that ENDS be regulated to prevent children and young adults from using the devices. The international well-being group encourages all nations to restrict advertising, regulate product characteristics, and ban use in public spaces. WHO reports that in 2020, ENDS are banned in 30 countries.