Electronic Cigarettes

In recent years, the popularity of electronic cigarettes has grown exponentially. Electronic cigarettes simulate smoking by vaporizing a solution that can be puffed, though they don't actually emit smoke. They therefore lack the smell and secondhand smoke associated with tobacco cigarettes, though there are still health risks.

Some important facts about electronic cigarettes:

• Most electronic cigarettes contain nicotine, which is addictive and can cause health problems.

• Electronic cigarettes should not be considered an effective smoking-cessation aid, according to the Food and Drug Administration (FDA) and the World Health Organization (WHO).

• Not enough is known about the health implications of electronic cigarettes, the FDA and WHO say. The unknowns include the amount of nicotine that is inhaled when using these products as well as what types of potentially harmful ingredients e-cigarettes might contain.

• "Known carcinogens and toxic chemicals" were detected in e-cigarettes examined by the FDA's Center for Drug Evaluation, Division of Pharmaceutical Analysis (DPA).

Can electronic cigarettes help you quit smoking?

In a survey, three quarters of the104 e-cigarette users surveyed said they had used the device to help themselves quit smoking, according to a report in the October 2011 issue of the International Journal of Clinical Practice.

However, both the FDA and the WHO say electronic cigarettes should be considered an alternative to smoking, not an effective smoking cessation aid. Both organizations say there is not enough information about the health implications of electronic cigarettes to make a call on their use as an aid.

H2:Studies are inconclusive. A 2010 study published in the Journal of Public Health Policy concludes that e-cigarettes show "promise" in helping reduce the number of tobacco-related health conditions and deaths. On the other hand, an undated study conducted by the Center for Global Tobacco Control at the Harvard School of Public Health suggests that smoking e-cigarettes may restrict people's airways faster than a conventional cigarette.

Additionally, there is some concern that flavor options like menthol and strawberry make electronic cigarettes more appealing to minors. As with tobacco cigarettes, the legal age to buy e-cigarettes is at least 18 in the U.S.; some states and localities have raised the legal age to 19. Flavored tobacco cigarettes were, for the most part, banned by the federal government in 2009.

The FDA and the Centers for Disease Control and Prevention (CDC) provide lists of safe methods to quit smoking. You can also visit a SmokeFree website for more information and guidance.

How do electronic cigarettes work?

Most models of electronic cigarettes are battery powered and consist of a cartridge that holds a liquid and an atomizer, which is the heating unit that vaporizes the liquid. When the user inhales the vapor, an LED lights up at the tip of the e-cigarette to mimic a real cigarette.

The liquid, often called "e-liquid," comes in several options. Some liquids are nicotine-free. Most solutions, however, contain some level of nicotine, which include low (6-9 milligrams of nicotine per milliliter of liquid), midrange (10-17 mg/ml), high (18-22 mg/ml) and extra-high (24-36 mg/ml). These numbers indicate the amount of nicotine in the e-cigarette, not how much is absorbed by the smoker. That data isn't available. Therefore, it's not possible to directly compare the amount of nicotine absorbed when smoking an e-cigarette versus a tobacco cigarette.

Liquids are also available in an array of flavors, such as a traditional menthol flavor or more exotic options like strawberry and pina colada. Some liquids also contain whole tobacco alkaloids (WTA). Each cartridge of liquid is equivalent to about 20 (or one pack) of cigarettes.

These devices are typically powered by rechargeable batteries, but there are some brands that are considered disposable. These last for about 500 puffs) and then can be thrown away. These models are typically less expensive than rechargeable options.

There are also automatic and manual versions of e-cigarettes. Automatic cigarettes emit a puff of vaporized liquid when puffed on. To work a manual e-cigarette, the user must press a small button on the side of the cigarette for a few seconds before inhaling the vapor. Some users prefer the manual versions, saying they deliver a more robust hit. Reviewers also say that the most important factor in any electronic cigarette is the atomizer, which determines how thick the vapor is, and thus how similar the experience is to smoking a tobacco cigarette.

As mentioned previously, there are three main components to an e-cigarette: the battery, atomizer and cartridge. In some electronic cigarettes, all three components are separate. These are called three-piece electronic cigarettes. When users want to change the cartridge (changing/adding liquid), they must dismantle all three pieces, remove the old cartridge, replace it, reassemble the filter and attach it to the main part of the cigarette, which houses the battery. Two-piece cigarettes, on the other hand, combine the atomizer and the cartridge component, making it easier to replace the e-liquid when needed. Because users must employ a new atomizer with each new cartridge, two-piece cigarettes tend to be more expensive. However, users say they tend to prefer them, despite the higher cost, because they are easier to use.