The Food and Drug Administration expects to publish its much-anticipated regulations for e-cigarettes in June, as the products are surging in popularity. In fact, sales are expanding so rapidly that some experts predict e-cigs will overtake sales of conventional smokes within the next decade.

"From our perspective, the rules are long overdue," said Erika Sward, assistant vice president of national advocacy at the American Lung Association, who noted the regulations have been in the works for about a year.

The FDA already regulates cigarettes, cigarette tobacco, roll-your-own tobacco and smokeless tobacco. Under the 2009 Family Smoking and Tobacco Control Act, the FDA can "deem" additional tobacco products to be subject to the Federal Food, Drug, and Cosmetic Act. Among other things, firms would be required to register with the FDA and submit product and ingredient listings, and include health warnings and take steps to prevent sales to underage consumers.

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"To date, FDA has not been able to fully assess the public health impacts of unregulated tobacco products," the FDA said in a statement sent to CBS MoneyWatch. "For example, some testing of e-cigarette cartridges has revealed significant variability in nicotine content and the presence of chemical constituents that raise concerns of toxicity."

Altria Group (MO) and Reynolds American (RAI), two of the biggest tobacco companies, are welcoming the FDA's efforts, arguing that the patchwork of existing state regulations fails to protect consumers against defective products, some of which have even exploded. The companies are lobbying the FDA to treat e-cigarettes differently than conventional smokes.

Some proponents of e-cigaretttes have claimed that they can be an effective smoking cessation tool. A study published last year found that people who wanted to quit smoking were about 60 percent more likely to be successful if they used e-cigarettes as opposed to other products such as nicotine patches or gum.

Industry critics, including the American Lung Association, counter that the evidence to back up these claims is inconclusive. A study released last month by the Johns Hopkins Bloomberg School of Public Health found that e-cigarettes generate some of the same dangerous chemicals found in traditional smokes.

"There is absolutely no federal oversight of e-cigarettes in terms of what is in them, how they are being marketed," said Sward of the American Lung Association, adding that e-cigarette makers are "following the Big Tobacco playbook" by offering flavored e-cigarettes that would appeal to underage smokers. "Really, what we are seeing are the same tactics that we saw 30, 40 years ago."

Altria, which is based in Richmond, Virginia, has put a 116-word warning on packs of its MarkTen e-cigarettes even though it wasn't legally obligated to do so. As Reuters noted, it said nicotine is "addictive and habit-forming" and that MarkTen isn't intended for women who are pregnant or breast-feeding or people being treated for depression or asthma. Spokesman Steve Callahan said the wording on the company's label was based the "available science."

In a statement to CBS MoneyWatch, Reynolds argued that the FDA needed to regulate e-cigarettes fairly.

"We believe if (the) FDA is going to regulate vapor products, then it should regulate all vapor products -- including open systems and the vape shops in which the liquid nicotine used in open systems is mixed or compounded -- to create a level playing field where all manufacturers are subject to equal treatment, including FDA inspection/registration/regulation, manufacturing standards and product clearance requirements," writes Richard J. Smith, a spokesman, in an email.

Whenever the regulations are issued, it will open another front in the decades-long battle that pits people trying to protect the public health against the rights of an industry selling an otherwise lawful product.