Even in these days of strict indoor clean air laws, you can still legally puff away in movie theaters, restaurants or even on a plane. You just have to use a cigarette that runs on a battery, not tobacco.

Electronic cigarettes — battery-powered devices that deliver a fine spray of nicotine without any flame or smoke — have been sold in this country for about three years now. Some people use them as a way to quit smoking real cigarettes. Unlike gum or patches, the devices mimic the sensation of smoking while providing the nicotine rush. Other people use them to get their cigarette fix in places where smoking is not allowed.

The Food and Drug Administration hasn't approved electronic cigarettes as an aid to quit smoking or for anything else. The agency has tried to stop the products from entering the country, but its authority over e-cigarettes is still being hashed out in courts. Meanwhile, the gadgets have developed a devoted fan base. On message boards and blogs, e-cigarette users have loudly and clearly proclaimed their allegiance to the devices.

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E-cigarettes — sold without age restrictions online, in some bars and clubs, and at the occasional mall kiosk — come with replaceable cartridges containing various levels of nicotine. The regular cartridges for NPRO cigarettes from NJOY, for example, contain 18 milligrams of nicotine, but you can also get a light version with 12 mg., an ultralight version with 6 mg. and even a nicotine-free version. The company says that, for a typical smoker, each cartridge would last about as long as a pack or pack-and-a-half of cigarettes. For comparison, a smoker would get about 20 mg. of nicotine from a single pack of regular cigarettes. Each cartridge also contains water and propylene glycol, a chemical that helps disperse the nicotine. (Propylene glycol also is a key component of fog made by fog machines, should you be curious.)

The cartridges come with a variety of flavors. Users of the No. 7 cigarette from SS Choice, for example, can choose from tobacco, menthol, blueberry, vanilla and other options — as well as a range of colors. The Hydro Imperial from Crown7 comes in white and black.

A starter pack of NPRO cigarettes containing 10 cartridges costs about $80. A starter pack of No. 7 cigarettes with five cartridges containing 16 mg. of nicotine each costs about $70. A starter pack of Hydro Imperial containing two cartridges with 18 mg. of nicotine each costs a little less than $40. All brands offer replacement cartridges of various strengths and flavors.

Claims: The FDA does not allow e-cigarette companies to market the devices as aids to quit smoking. But both Ron MacDonald, president of Crown7, and Jonas Joiner, marketing director of SS Choice, say they know of plenty of ex-smokers who used e-cigarettes to wean themselves off the real thing. (A spokesperson for NJOY declined to comment because the company is currently in litigation with the FDA.) Some users manage to give up nicotine completely, but others just switch from one source of nicotine to another, MacDonald says. "A lot of people continue to use our product instead of regular cigarettes, and they feel better," he says.

The NJOY website says that an e-cigarette provides "all the pleasure and sensation of smoking without all the health, social and economic problems." The SS Choice site says that its cigarette is more convenient and cost-effective than a regular cigarette and doesn't contain "the thousands of additives and chemicals" found in cigarettes. The Crown7 site says that its cigarettes are "the latest way to get a nicotine fix without most of the harmful effects associated with smoking."

The bottom line: Electronic cigarettes certainly have their appeal in a gadget-centric world, but many questions remain, says Thomas Eissenberg, director of the clinical behavioral pharmacology laboratory at Virginia Commonwealth University in Richmond. For one thing, he says, e-cigarettes have never been studied for smoking cessation, so nobody knows if they are any more or less effective than other nicotine replacement products such as gums or patches.

Also, Eissenberg says, it's not very clear what smokers are getting when they take a drag on an e-cigarette. In a study published in July, Eissenberg and colleagues had 32 smokers take puffs on two brands of e-cigarettes, the NPRO with 18 mg. of nicotine and a model from Crown7 with 16 mg. Each smoker took 20 normal puffs, with a short break after the first 10. The study found that electronic cigarettes did reduce the urge to smoke, but, importantly, neither brand delivered measurable amounts of nicotine to the users' bloodstreams. Eissenberg suspects that the devices are so similar to cigarettes that they can help fill the psychological urge to smoke even if they don't provide much nicotine.

"I've been told that you can get nicotine from these things if you really work at it," Eissenberg adds. He believes it's possible that real-life users can get all the nicotine they need by drawing hard, inhaling deeply and taking many puffs. He's considering running a study under more realistic conditions with smokers who are already familiar with e-cigarettes.

In another study published in July, researchers at UC Riverside used a smoking machine to show that it takes more suction to get nicotine from an electronic cigarette than from a regular cigarette.

Eissenberg believes that electronic cigarettes may be worth a try for someone who wants to quit smoking. "Using it for six to eight weeks could be good," he says. But long-term use is another matter, he adds. Although propylene glycol is generally considered to be safe for humans, he warns that nobody knows the effects of deeply inhaling the compound for hours at a time on a daily basis. "I don't know that that's safer than cigarettes," he says.

Adam Leventhal, director of USC's health, emotion and addiction laboratory, says that electronic cigarettes are almost certainly safer than cigarettes. Still, he believes that nicotine patches and gums would probably be better options for anyone looking to quit smoking. Such products are regulated by the FDA, and users can be confident that they're getting the amount of nicotine that they expect. And because e-cigarettes are so much like regular cigarettes, he's concerned that they won't do much to break the actual habit of smoking. "We always tell people who are trying to quit smoking that they should get rid of anything that reminds them of smoking, including ashtrays and cigarettes," he says. "Electronic cigarettes could be a trigger."

Experts and policymakers who criticize electronic cigarettes are missing a great chance to improve public health, says Carl Phillips, a former associate professor of public health at the University of Alberta in Edmonton and creator of tobaccoharmreduction.org, an academic website that promotes alternatives to smoking.

He says the effects of propylene glycol should be studied, but he's confident that e-cigarettes are at least 95% safer than actual cigarettes. "If users are engaging in something that feels the same as smoking but doesn't involve any smoke, that's great," he says.

(Por Chris Woolston, Los Angeles Times, 03/08/2010)