Contributor: Raul Seballos, MD
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Electronic cigarette (e-cig) manufacturers claim that they are a safer alternative to cigarettes. But two important questions must be addressed:
- Are e-cigs safe?
- Are they effective for helping people quit smoking?
E-cigs are battery-powered devices. They are the same size and shape as standard cigarettes but generate a vapor containing one-third to one-half the nicotine, which users inhale. A lithium battery within each e-cig is attached to a heating element and vaporizes liquid nicotine either with propylene glycol or vegetable glycerin. This vaporization, or “vaping,” allows a person to inhale in a way that mimics smoking. However, e-cigs are non-flammable and deliver nicotine without potentially toxic and carcinogenic compounds such as carbonyls, volatile organic compounds, nitrosamines and heavy metals.
Earlier this year, the Centers for Disease Control and Prevention (CDC) reported that 1 in 5 U.S. cigarette smokers have tried the readily available e-cigs. It also reported that e-cig use doubled among high school students, from 4.7 percent in 2011 to 10 percent in 2012. In addition:
- E-cig sales have doubled every year since their introduction in 2007
- The number of adults using e-cigs has doubled since 2010
- The $1.5 billion U.S. e-cig industry tripled its sales in 2013 due to increased marketing ads and sponsorships
- In the past three years, e-cig advertising grew from $7.2 million to $20.8 million
Safety: Knowns and unknowns
Repeated inhalation of propylene glycol or vegetable glycerin is known to cause airway irritation. But no long-term data is available on the effects of e-cigs on the lungs.
Propylene glycol is a FDA-approved food additive commonly found in toothpaste, deodorants and moisturizers, and it is used in theatrical smoke. The FDA has found that it contains detectible levels of known carcinogens and diethylene glycol, an antifreeze ingredient.
However, Roswell Park Cancer Institute researchers recently reviewed 12 e-cig brands and found that toxicant levels were 9 to 450 times lower than in cigarette smoke.
Help quitting: Inconclusive results
Whether e-cigs can safely help people quit smoking remains to be seen. Since e-cig manufacturers have not submitted an application to the FDA for their use in smoking cessation, e-cigs are not currently FDA-approved for such use.
E-cigs have been shown to be as effective as nicotine inhalers in reducing both craving and withdrawals effects. Another study found that e-cigs may be comparable but were no more effective for smoking cessation than nicotine patches or placebo e-cigs after six months.
Notably, some e-cigs emitted different amounts of nicotine with each puff, perhaps due to inconsistency or lack of quality control in manufacturing.
One concern is whether e-cigs may increase nicotine addiction among younger users. Flavored e-cigs have the potential to entice new smokers — especially students in middle school and high school. During 2011–2012, the number of U.S. middle and high school students who experimented and used ecigs doubled, resulting in an estimated 1.78 million students having ever used e-cigarettes as of 2012, according to the CDC.
The two take-home messages are:
- E-cigs may offer an alternative in future smoking cessation programs, but long-term studies on product safety and efficacy are lacking.
- E-cigs contain ingredients that may be toxic to humans although levels are lower than in standard cigarettes.
Next step: Better regulation
On Sept. 24, 2013, at least 40 U.S. State Attorneys General urged the FDA for more regulation on the sale and advertising of e-cigs.
The FDA may act soon on the American Medical Association’s recommendation that e-cigs be classified as nicotine drug-delivery devices. This would make e-cigs subject to FDA regulations regarding identity, strength, purity, packaging and labeling, with instructions and warnings that include age restrictions.
Some states have already passed e-cig regulations. California has banned online e-cig advertising. Utah, North Dakota, Arkansas, New Jersey, and Washington, D.C. have banned e-cig use indoors, and many states are likely to follow suit.