The federal government wants to ban sales of electronic cigarettes to minors and require health warning labels and approval for new products.

While the proposal issued Thursday by the Food and Drug Administration won't immediately mean changes for the popular devices, the move is aimed at eventually taming the fast-growing e-cigarette industry.

Some smokers like e-cigarettes because the nicotine-infused vapor looks like smoke but doesn't contain the thousands of chemicals, tar or odor of regular cigarettes. Some smokers use e-cigarettes as a way to quit smoking tobacco, or to cut down. However, there's not much scientific evidence showing e-cigarettes help smokers quit or smoke less, and their safety is unclear.

Michael Cummings, a nationally renowned tobacco researcher at the Medical University of South Carolina, said he was pleased with the FDA's proposal.

Cummings said the products might be playing a role in decreasing consumption of tobacco cigarettes among adults, particularly among those ages 18 to 24. He expects future figures on smoking rates to continue to reflect that trend.

"The FDA's proposals are measured and didn't go crazy by trying to ban flavors and marketing. I don't think that's the way to go," said Cummings, adding he is pleased that proposals seek to keep e-cigarettes out of the hands of minors.

The FDA's proposal to license manufacturers also is needed, he said, noting that it will help keep a check on products, particularly those made in China.

While Cummings said the evidence that e-cigarettes can help smokers quit tobacco cigarettes is mixed, he suspects it's likely playing a role.

"My interest is in preventing cancer," said Cummings, reiterating that it's the tar and the array of chemicals tobacco companies put in cigarettes that causes cancer. "Nicotine doesn't cause cancer, but it does cause addiction."

He compared nicotine addiction to caffeine addiction, which has minor health consequences.

The e-cigarette industry started on the Internet and at shopping-mall kiosks and has rocketed from thousands of users in 2006 to several million worldwide who can choose from more than 200 brands. Sales are estimated to have reached nearly $2 billion in 2013.

Reactions from Charleston area retailers to the proposed regulations were mixed.

"As long as they don't try to tax away people's chances of reducing their health risks, we support responsible regulations," said Charlie Howle, general manager of Charleston Electronic Cigarettes, which has shops in West Ashley and Summerville. "We certainly believe that we want to keep everything out of the hands of minors."

Rick Kosinski, co-owner of Pleasant Ecigs' four stores in Mount Pleasant, North Charleston and Sumter, said the regulations are unnecessary.

"I don't want them to regulate it, but they are going to anyway," Kosinski said. "They are just putting their nose in something they shouldn't. There is really nothing to regulate."

Pleasant Ecigs posts signs in its stores prohibiting the sales of its products to minors and won't sell to someone online if it can't verify their age, Kosinski said. It also puts the nicotine content on the bottle.

He suspects big tobacco companies are pushing for regulations because they are losing customers to electronic cigarettes.

"If the price goes up beyond the current sales taxes like it did for cigarettes, people will still buy them," Kosinski said.

Operators of Ecig Charleston declined to comment.

The FDA said the proposal sets a foundation for regulating the products but the rules don't immediately ban the wide array of flavors of e-cigarettes, curb marketing on places like TV or set product standards.

Any further rules "will have to be grounded in our growing body of knowledge and understanding about the use of e-cigarettes and their potential health risks or public health benefits," FDA Commissioner Dr. Margaret Hamburg said.

Members of Congress and public health groups have raised concerns over e-cigarettes and questioned their marketing tactics.

"When finalized (the proposal) would result in significant public health benefits, including through reducing sales to youth, helping to correct consumer misperceptions, preventing misleading health claims and preventing new products from entering the market without scientific review by FDA," said Mitch Zeller, the director of the FDA's Center for Tobacco Products.

Public health advocates said the FDA proposal is a critical step in reining in marketing of the new products. But they also said it comes after an "inexcusably long delay," pointing out that the FDA first announced its plans to regulate e-cigarettes in April 2011.

"It is inexcusable that it has taken the FDA and the Administration so long to act. This delay has had serious public health consequences as these unregulated tobacco products have been marketed using tactics and sweet flavors that appeal to kids," the Campaign for Tobacco-Free Kids said in a statement.

Once the new rules are finalized, the agency could propose more restrictions on e-cigarettes. Officials didn't provide a timetable for that action.

The FDA said the public, members of the industry and others will have 75 days to comment on the proposal. The agency will evaluate those comments before issuing a final rule but there's no timetable for when that will happen. The regulations will be a step in a long process that many believe will ultimately end up being challenged in court.

The Associated Press contributed to this report.