The future of the booming electronic cigarette business will be decided Thursday when the Food and Drug Administration is expected to propose sweeping new rules for the unregulated, multibillion dollar industry.

Until now, the public health implications of the tobacco alternative are still widely mixed. While many regard the nicotine-laced water vapor as a potential substitute for cancer-causing cigarette smoke, health experts are still studying the range of possible health effects the product has on users, SmokeFree Wisconsin Executive Director Maureen Busalacchi said.

Since their first sales in 2007, e-cigarettes have seen a global boom, with total sales nearly doubling last year to $1.7 billion, according to CNBC.

However, the new industry barely rivals the $350 billion tobacco industry, which serves America’s 42 million smokers, Tobacco Atlas reported.

The new FDA regulations will cover cigars and pipe tobacco, products that have been largely unregulated until now, and ban the sale of e-cigarettes and all other tobacco products to individuals under 18 years of age, the New York Times reported.

Thursday’s release of the regulations will be hundreds of pages long and will likely set off nationwide lobbying efforts from the e-cigarette industry, according to the New York Times.

E-cigarettes vaporize liquid nicotine, giving users a nicotine rush without the harmful carcinogenic effects of tobacco smoke. Depending on the product, e-cigarettes contain around 20 chemicals while conventional cigarettes contain more than 400 chemicals, according to the Electronic Cigarette Association.

Michael Ellis, owner of Madison smoke-shop Knuckleheads, said he has seen e-cigarettes become increasingly popular products.

Ellis said e-cigarettes that do not contain any nicotine are widely popular among Madison’s college population.

“College age kids just enjoy smoking them recreationally, just because it’s fun to do once in a while,” he said. “They taste good, you can pass them around with your friends and, most importantly, it’s not nearly as harmful as anything else that you’d be putting in your lungs other than air.”

E-cigarettes are also highly popular among individuals looking to quit smoking, as smokers can feed their nicotine addiction without the harmful effects of tobacco smoke, Ellis said. Because there is no second hand smoke or carcinogens, e-cigarettes are a healthier option for smokers, he said.

While supporters contend e-cigarettes are healthier than conventional cigarettes, experts have raised concerns on the effect the emerging industry is having on the nation’s youth.

According to a report released by the Centers for Disease Control and Prevention, between 2011 and 2012 the rate of minors using e-cigarettes more than doubled from 4.7 percent to 10 percent. The study also found that more than 75 percent of those minors also smoke conventional cigarettes.

Busalacchi rejected the notion that e-cigarettes are a safe alternative to conventional cigarettes due to the many uncertainties, which the FDA rules will likely address.

“There’s a whole list of folks who would not be recommended to use these products,” Busalacchi said. “That tells us that these aren’t necessarily safe. We don’t know enough about them.”

Brenda McIntire contributed reporting to this story.