Electronic cigarette

Two electronic cigarette models. From top down: RN4072 "pen-style" and CT-M401. A spare detached battery is also shown below each model.

A DSE-901 electronic cigarette exhibiting another common design, that of an ordinary cigarette.

An electronic cigarette, otherwise known as a personal vaporizer, is a battery-powered device that provides inhaled doses of nicotine by way of a vaporized solution. It is an alternative to smoked tobacco products, such as cigarettes, cigars, or pipes. In addition to nicotine delivery, this vapor also provides a flavor and physical sensation similar to that of inhaled tobacco smoke, while no tobacco, smoke, or combustion is actually involved in its operation.

An electronic cigarette usually takes the form of some manner of elongated tube, though many are designed to resemble the outward appearance of real smoking products, like cigarettes, cigars, and pipes. A common design is also the "pen-style", so named for its visual resemblance to a ballpoint pen. Most electronic cigarettes are reusable devices with replaceable and refillable parts. A number of disposable electronic cigarettes have also been developed.

The electronic cigarette was first developed in Beijing, China, by SBT Co. in 2003, a company now controlled by the Golden Dragon Group Ltd. Since its initial release, it has been gaining popularity world-wide. In the last several years, it has undergone several laboratory tests, with mostly positive results.

Operation

A disassembled cigarette-shaped electronic cigarette.
A. LED light cover
B. battery (also houses circuitry)
C. atomizer (heating element)
D. cartridge (mouthpiece).

In automatic models, when a user inhales through the device, air flow is detected by a sensor, which activates a heating element that vaporizes a nicotine solution stored in the mouthpiece. On manual models, the user must depress a button to activate the heating element to produce vapor. It is this vapor that is inhaled by the user. On most models an LED on the opposite end of the device is also activated during inhalation, which serves as an indicator of use. Color of the LED is usually a matter of preference, as the most widely used electronic cigarettes come with options for many different colors.

Components

While electronic cigarettes take many forms, they each generally employ the same basic components: a mouthpiece, a heating element, a rechargeable battery, and various electronic circuits.

Mouthpiece (cartridge)

The mouthpiece is a small disposable plastic cup affixed to the end of the tube. Inside, the piece contains an absorbent material that is moistened with a flavored nicotine liquid solution. The mouthpiece is referred to in the industry as a "cartridge". When the liquid in the cartridge has been depleted, it can either be refilled by the user, or replaced with another pre-filled cartridge.

Heating element (atomizer)

The heating element serves to vaporize the liquid in the mouthpiece so that it can be inhaled. This component is referred to in the industry as an "atomizer". Some models combine atomizer and cartridge into one disposable component referred to as "cartomizer".

An electronic cigarette battery connected to a USB charger.

Battery and electronics

Most electronic cigarettes employ a lithium-ion rechargeable battery to power the heating element. Battery life varies depending on the battery type and size, frequency of use, and operating environment. Many different battery charger types are available, such as wall outlet, car, and USB. The battery is generally the largest component of an electronic cigarette.

Most electronic cigarettes employ an electronic airflow sensor to automatically activate upon inhalation, while some models instead have a manual button that the user must press while inhaling. Various other electronic circuits are usually employed as well, such as a timed cutoff switch to prevent overheating, and an LED to signal activation of the device. An orange-colored light is often chosen for its visual resemblance to actual burning tobacco in the front of the cigarette.

While some larger electronic cigarette models employ an independently replaceable standard-size battery cell, many models are too small to house a standard-size cell and instead require a proprietary component made by the electronic cigarette manufacturer. For those models, the battery and electronic components are housed within a single replaceable part, which is generally referred to in the industry simply as the "battery" — even though it actually contains many other components as well.

Nicotine solution

Nicotine solutions usually consist of nicotine diluted in propylene glycol, or less commonly, glycerin, both common food additives. They also commonly have a variety of different flavorings added. Nicotine solutions sold separately for use in refillable cartridges are commonly referred to as "e-liquid" or "e-juice". Solutions are available in a variety of different flavors and nicotine concentrations. Nicotine concentrations range from high doses (to mimic the content of regular cigarettes) to midrange and low doses.

Dosage generally follows the same patterns as regular, light, and ultra-light strength cigarettes. Solutions are also available which contain little or no nicotine. Some flavor varieties attempt to resemble traditional cigarette types, such as regular tobacco and menthol, and some even attempt to mimic specific cigarette brands, such as Marlboro or Camel. Solutions are also available with other flavorings, such as strawberry, orange, mint, vanilla, caramel, coffee.

Below are some of the different liquid solution compositions available:

Substance	Recipe 1	Recipe 2	Recipe 3	Recipe 4	Recipe 5
Propylene glycol	85%	80%	90%	80%	<65%
Nicotine	6%	4%	2%	0.1%	<3%
Glycerol	2%	5%	-	5%	<20%
Tobacco essence	-	4%	4.5%	1%	<5%
Essence	2%	-	1%	1%	<5%
Organic acid	1%	-	-	2%	<1%
Anti-oxidation agent	1%	-	-	-	-
Butyl valerate	-	1%	-	-	-
Isopentyl hexonate	-	1%	-	-	-
Lauryl laurate	-	0.6%	-	-	-
Benzyl benzoate	-	0.4%	-	-	-
Methyl octynicate	-	0–5%	-	-	-
Ethyl heptylate	-	0.2%	-	-	-
Hexyl hexanoate	-	0.3%	-	-	-
Geranyl butyrate	-	2%	-	-	-
Menthol	-	0.5%	-	-	-
Citric acid	-	0.5%	2.5%	-	-
Water	-	-	-	2.9%	<10%
Alcohol	-	-	-	8%	-
2,3,5-Trimethylpyrazine	-	-	-	-	<1%
2,3,5,6-Tetramethylpyrazine	-	-	-	-	<1%
2,3-Dimethylpyrazine	-	-	-	-	<1%
Acetylpyrazine	-	-	-	-	<1%
Terpineol	-	-	-	-	<1%
Ethyl maltol	-	-	-	-	<1%
Guaiacol	-	-	-	-	<1%
Acetylpyridine	-	-	-	-	<1%
Octalactone	-	-	-	-	<1%

History

The electronic cigarette was first developed in 2003 by SBT Co. Ltd., a Beijing based firm, which is now controlled by the Golden Dragon Group Ltd. In 2004, Ruyan took over the project to further develop the emerging technology. Ruyan officially absorbed SBT Co. Ltd. and their name was changed to SBT RUYAN Technology & Development Co., Ltd. In April of 2006, the electronic cigarette was brought to Europe, and officially launched at the "RUYAN" Overseas Promotion Conference in Austria. After its introduction, this product was adapted to the European market and marketed as the "Electro fag". In 2007, Reuters visited SBT RUYAN in Beijing, which drew media attention to the technology.

Health issues

The health effects of using electronic cigarettes are currently unknown. Some electronic cigarette companies claim that the harmful material produced by the combustion of tobacco in traditional cigarettes is not present in the atomized liquid of electronic cigarettes. Some have also marketed electronic cigarettes as a way to curtail an addiction to nicotine, although international health organizations have stated they may not be marketed as a cessation device. Despite these claims, a number of regulatory agencies have issued warnings regarding the health effects of these products. The recently-formed Electronic Cigarette Association aims to eliminate unsubstantiated health claims made by electronic cigarette companies, and those companies that wish to participate in the association must agree to refrain from making such claims.

Various findings

Food and Drug Administration (USA)

In May 2009, the US FDA's Division of Pharmaceutical Analysis tested the contents of cartridges by two vendors. Trace amounts (detectable, but not measurable) of diethylene glycol was found in one of the seventeen cartridges. In addition, tobacco-specific nitrosamines (TSNAs) were detected in some of the cartridges tested which used tobacco flavoring. Further concerns were raised over inconsistent amounts of nicotine delivered when drawing on the device. In July 2009, the FDA issued a press release discouraging the use of electronic cigarettes and repeating previously stated concerns that electronic cigarettes may be marketed to young people and lack appropriate health warnings.

The FDA's May 2009 study was reviewed in July 2009 by scientific consulting firm Exponent, Inc., in a report commissioned by the manufacturer of one of the electronic cigarettes tested by the FDA. Some of the criticisms in Exponent's report are poor standards of documentation and analysis and failure to perform relevant comparisons to FDA-approved nicotine replacement therapy products, which Exponent claims contain TSNA levels comparable to those of e-cigarettes. The study concludes that the FDA's claims of potential adverse health effects were not supported by the study.

Health Canada

On March 27, 2009, Health Canada issued an advisory against electronic cigarettes. The advisory stated "Although these electronic smoking products may be marketed as a safer alternative to conventional tobacco products and, in some cases, as an aid to quitting smoking, electronic smoking products may pose risks such as nicotine poisoning and addiction."

World Health Organization

The World Health Organization proclaimed in September 2008 that it does not consider the electronic cigarette to be a legitimate smoking cessation aid, and demanded that marketers immediately remove from their materials any suggestions that the WHO considers electronic cigarettes safe and effective. The WHO states that to its knowledge, "no rigorous, peer-reviewed studies have been conducted showing that the electronic cigarette is a safe and effective nicotine replacement therapy. WHO does not discount the possibility that the electronic cigarette could be useful as a smoking cessation aid." WHO Tobacco Free Initiative director ad interim Douglas Bettcher states, "If the marketers of the electronic cigarette want to help smokers quit, then they need to conduct clinical studies and toxicity analyses and operate within the proper regulatory framework. Until they do that, WHO cannot consider the electronic cigarette to be an appropriate nicotine replacement therapy, and it certainly cannot accept false suggestions that it has approved and endorsed the product."

Health New Zealand

The presence of trace amounts of TSNAs in electronic cigarette vapor was previously documented in an analysis done by the Health New Zealand medical journal in October 2008. However, unlike the FDA study, the Health New Zealand study conducted detailed quantitative analysis and concluded that carcinogens and toxicants are present only below harmful levels. Overall, the product tested was deemed a "safe alternative to smoking."

Electronic Cigarette Association

The Electronic Cigarette Association is a trade association made up of electronic cigarette producers, distributors and retailers, whose aim is to speak on behalf of the electronic cigarette industry, especially in response to health concerns, and to help institute industry standards. The group was formed in 2009 and is headquartered in Washington, D.C.. Its president and spokesman is former United States congressman Matt Salmon. Since the group formed, Salmon has issued several public statements via YouTube in response to FDA press statements.

Legal status by region

Due to the relative novelty of the technology and the possible relationship to tobacco laws and medical drug policies, electronic cigarette legislation and public health investigations are currently pending in many countries.

• In Australia, the sale of electronic cigarettes containing nicotine is illegal.
• In Brazil electronic cigarettes sales, importation or advertisement of any kind are forbidden. Anvisa, the Brazilian health and sanitation federal agency, found the current health safety assessments about e-cigarettes not to be yet satisfactory to make the product eligible to be approved for commercialization.
• In Canada, as of March 2009, imports, sales, and advertising is banned. In March 2009, Health Canada also advised Canadians not to purchase or use any electronic smoking products. Health Canada cited the Food and Drugs Act, stating that electronic smoking products containing nicotine require market authorization before they can be imported, marketed, or sold. No market authorization has been granted for any electronic smoking product.
• In The Netherlands, use of electronic cigarettes is allowed, but advertising is forbidden pending European Union legislation.
• In New Zealand, the Ministry of Health has ruled that the Ruyan e-cigarette falls under the requirements of the Medicines Act, and cannot be sold except as a registered medicine. They do note, as it is not a tobacco product, it is permissible to advertise it.
• In Panama, importation, distribution and sale has been prohibited since June 2009. The Ministry of Health cites the FDA findings as their reason for the ban.
• In the United Kingdom, electronic cigarette use is currently unrestricted.
• In the United States, as of November 2009, use is unrestricted, however some imports are being seized. The FDA considers e-cigarettes to be a nicotine delivery system, subject to its approval.
  • In California, the governor vetoed a bill that would have banned sales, stating "[...] If adults want to purchase and consume these products with an understanding of the associated health risks, they should be able to do so [...]"