FALL RIVER, Mass. — During 34 years of smoking, Carolyn Smeaton has tried countless ways to reduce her three-pack-a-day habit, including a nicotine patch, nicotine gum and a prescription drug. But stop-smoking aids always failed her.
Then, having watched a TV infomercial at her home here, Ms. Smeaton tried an electronic cigarette, which claimed to be a less dangerous way to feed her addiction. The battery-powered device she bought online delivered an odorless dose of nicotine and flavoring without cigarette tar or additives, and produced a vapor mist nearly identical in appearance to tobacco smoke.
“I feel like this could save my life,” said Ms. Smeaton, 47, who has cut her tobacco smoking to a pack and a half daily, supplemented by her e-cigarette.
That electronic cigarettes are unapproved by the government and virtually unstudied has not deterred thousands of smokers from flocking to mall kiosks and the Internet to buy them. And because they produce no smoke, they can be used in workplaces, restaurants and airports. One distributor is aptly named Smoking Everywhere.
The reaction of medical authorities and antismoking groups has ranged from calls for testing to skepticism to outright hostility. Opponents say the safety claims are more rumor than anything else, since the components of e-cigarettes have never been tested for safety.
In fact, the Food and Drug Administration has already refused entry to dozens of shipments of e-cigarettes coming into the country, mostly from China, the chief maker of them, where manufacture began about five years ago. The F.D.A. took similar action in 1989, refusing shipments of an earlier, less appealing version, Favor Smoke-Free Cigarettes.
“These appear to be unapproved drug device products,” said Karen Riley, a spokeswoman for the agency, “and as unapproved products they can’t enter the United States.”
But enough of the e-cigarettes have made their way into the country that they continue to proliferate online and in the malls.
For $100 to $150 or so, a user can buy a starter kit including a battery-powered cigarette and replaceable cartridges that typically contain nicotine (though cartridges can be bought without it), flavoring and propylene glycol, a liquid whose vaporizing produces the smokelike mist. When a user inhales, a sensor heats the cartridge. The flavorings include tobacco, menthol and cherry, and the levels of nicotine vary by cartridge.
Propylene glycol is used in antifreeze, and also to create artificial smoke or fog in theatrical productions. The F.D.A. has classified it as an additive that is “generally recognized as safe” for use in food. But when asked whether inhaling it was safe, Dr. Richard D. Hurt, director of the Nicotine Dependence Center at the Mayo Clinic, said, “I don’t think so, but I’m not sure anyone knows for sure.”
Of the e-cigarettes themselves, Dr. Hurt added: “We basically don’t know anything about them. They’ve never been tested for safety or efficacy to help people stop smoking.”
Public health officials also worry that the devices’ fruit flavors, novelty and ease of access may entice children.
“It looks like a cigarette and is marketed as a cigarette,” said Jonathan P. Winickoff, an associate professor at the Massachusetts General Hospital for Children and chairman of the American Academy of Pediatrics Tobacco Consortium. “There’s nothing that prevents youth from getting addicted to nicotine.”
Sales and use of electronic cigarettes are already illegal on safety grounds in Australia and Hong Kong, and some other countries regulate them as medicinal devices or forbid their advertising. So far the United States has focused only on stopping them at the border, although Senator Frank R. Lautenberg, Democrat of New Jersey, has asked the drug agency to take them off the market until they can be tested.
Distributors of electronic cigarettes fear that a bill making its way through Congress that would give the F.D.A. the authority to regulate tobacco could be used to put them out of business as well. The bill has passed the House and could be taken up by the Senate this week.
The only American study of electronic cigarettes, now under way at Virginia Commonwealth University and financed by the National Cancer Institute, deals not with the kind of safety questions raised by propylene glycol but rather with the amount of nicotine processed by the bodies of the products’ users.
Another study, conducted this year at the University of Auckland in New Zealand and financed by Ruyan, an electronic cigarette company, shows that users typically receive 10 percent to 18 percent of the nicotine delivered by a tobacco cigarette.
Smoking Everywhere, a Florida-based distributor of electronic cigarettes, sued the F.D.A on April 28, claiming that the agency did not have jurisdiction to refuse the imported devices.
“The F.D.A. has the power to regulate Nicorette gum and the like because it is marketed as a smoking cessation product,” said Kip Schwartz, a lawyer for Smoking Everywhere. But the company says its products are a cigarette alternative for adult enjoyment and make no claims to help smokers quit, Mr. Schwartz added.
Matt Salmon, a spokesman for the Electronic Cigarette Association, which represents six distributors, said e-cigarettes delivered nothing more than a mixture of nicotine and water vapor and emitted “no carcinogens.” The association declined to give sales figures, but said that “hundreds of thousands” of people used the products and that the average age of those users was the mid-40s.
“It’s a really good alternative for people who smoke tobacco,” Mr. Salmon said.
Edwin Schwab, who quit smoking regular cigarettes last year after trying e-cigarettes, likes them so much he has started selling them at a mall kiosk in Providence, R.I.
Mr. Schwab took his e-smoke along when he went out one night, he said, “and when everyone was smoking outside in the cold, I just stood in the warm bar, smoking.”