Nobody knows yet what the long-term effects of “vaping” will be. (MAURO GRIGOLLO/ISTOCKPHOTO)

Maybe a friend or family member uses one. Maybe you’ve seen one being fired up in a place where you thought smoking was banned, such as a restaurant or sporting arena. Or maybe you’re using one yourself to try to kick a tobacco habit.

Whatever your experience is with electronic cigarettes, it appears that the battery-powered devices, which deliver a form of nicotine and mimic the feel of traditional cigarettes, are here to stay. Sales grew from about $500 million in 2012 to an estimated $1.5 billion in 2013. That’s a fraction of the tobacco cigarette market — roughly $100 billion per year — but it reflects rapid growth, in contrast to the steady decline in tobacco cigarette sales.

E-cigarettes are marketed as a more socially acceptable alternative to smoking. But what exactly are users — and the people around them — breathing in? Are the cigarettes safe? And with kid- friendly flavors such as Cherry Crush, Peach Schnapps and Vivid Vanilla, who are they really being marketed to? Here are answers to some key questions about electronic cigarettes.

What’s in them?

The main component is a refillable or replaceable cartridge of liquid “juice” that contains nicotine, solvents and flavors. When users draw on the device, it causes the battery to heat the liquid solution, which is then atomized into an inhalable vapor. The claimed levels of nicotine vary. The Blu brand of e-cigs, for example, offers cartridges of varying strengths, from no nicotine to approximately 13 to 16 milligrams, with each cartridge containing enough for 250 or more “puffs.” Some other brands list nicotine as a percentage of volume. Less clear is what’s used to create the piña colada, vanilla, bubblegum and other flavors.

How are they regulated?

At the moment, they aren’t. The Food and Drug Administration is expected soon to release a proposed rule that would allow the agency to regulate them as they do other tobacco products. That could result in restrictions on advertising or sale to minors and would probably require companies to disclose ingredients and conform to certain manufacturing standards. In the meantime, some states and municipalities have enacted bans on e-cigarettes in public parks and indoor venues where cigarette smoking isn’t allowed.

Are they safe to use?

We don’t know yet. They expose users and people around them to fewer toxins than tobacco cigarettes, but that doesn’t mean they’re risk-free. Nicotine is very addictive, so e-cigs — especially the fruit- and candy-flavored ones, health officials warn — could hook kids and teens on the stimulant or serve as a gateway to real cigarettes. And because they’re unregulated, you don’t necessarily know what’s in them. In 2009, the FDA detected diethylene glycol, a toxic chemical used in antifreeze, in some e-cig samples and carcinogens called nitrosamines in others.

Questions also linger over secondhand “vapor.” A December 2013 study compared exhaled vapor from three e-cigarette brands with exhaled tobacco smoke and found that the e-cig vapor contained about one-tenth the level found in tobacco smoke. But the researchers didn’t test for some of the other potentially unsafe components of vapor that earlier studies had found, including formaldehyde and metal particles.

Do they help smokers quit?

They might, though they’re not approved for that by the FDA. And as with approved quitting methods, the results aren’t that impressive. In a study of 657 smokers published last fall, e-cigs were about as effective as nicotine patches and were slightly better than placebo e-cigarettes, which contained no nicotine. But the differences were minor, and the overall number of people who quit with any method was low. After six months, about 7 percent of those in the e-cigarettes group and 6 percent of those who used nicotine patches stopped smoking, vs. 4 percent of those who used placebo e-cigs.

Bottom line

The main reason it’s so hard to say whether e-cigarettes are safe is that they haven’t been around long enough to know. It took decades for the risks of tobacco cigarettes to emerge, and nobody knows yet what the long-term effects of “vaping” will be. If you’re trying to give up real cigarettes, stick with better-studied methods: nicotine gum, patches and counseling. And if you don’t smoke, don’t start with e-cigs just for fun.

Copyright 2014. Consumers Union of United States Inc.

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