The list of places you can puff on an e-cigarette in Minneapolis could soon be much shorter.

City Council Member Cam Gordon is pitching a proposal that would put the vapor-producing devices in the same category as old-fashioned cigarettes — banning their use in indoor public spaces.

New e-cigarette restrictions in the city would expand on a recent change in state law that forbids use of the devices in and around schools, hospitals, public university campuses and hospitals. The tighter rules would mirror those enacted or being considered in other cities, including Bloomington, Duluth and Mankato.

Gordon said the state's largest city should act for two main reasons: the potential health risks posed to bystanders who inhale e-cigarettes' nicotine vapor, and the prospect that the devices are helping to attract a new generation of smokers.

Sellers and users of the battery-powered cigarettes, meanwhile, argue that additional restrictions would be heavy-handed, overstating the risk of e-cigarettes, limiting businesses and pushing users of the device into traditional smokers' areas — putting them at an even greater risk.

Chris Tipton, president of Minnesota Vapers Advocacy, said there's not enough research to show harm from secondhand vapor.

Gordon said he once thought of e-cigarettes as a safer alternative to smoking. But after looking more at how the products are sold and reports from young people about their smoking habits, he began changing his mind. Gordon said his recommendation was prompted in part by findings from the Minneapolis Youth Congress, a teen advisory group that made e-cigarette restrictions a part of their platform.

"Now I've learned from this process, and from talking to Health Department folks, and watching the industry that [e-cigarettes] are actually being used as a way to get people into nicotine addiction and as a moneymaker for those businesses," he said. "It's not about health. It's about profit and making money."

Lara Pratt, manager of the Minneapolis Health Department's Healthy Living Initiative, pointed to a study published in the journal of the American Society of Heating, Refrigerating and Air-Conditioning Engineers, a group that develops indoor, air quality standards. That study suggested that chemicals formed in the vaporizing process, including formaldehyde, could pose health risks — and that e-cigarettes' use should be regulated to help minimize those hazards.

"Because they're not regulated, we don't know exactly what's in there," Pratt said.

But Tipton noted a different study from a Drexel University researcher who concluded that people who sit near or pass by others using e-cigarettes face no significant health risk.

Tipton said the Vapers group supports keeping e-cigarettes away from children and teens, but that restrictions would hurt adults looking for an alternative to smoking.

"It explicitly eliminates a very big incentive to get folks to switch to a healthier option. And it legally implies that there's no difference between smoking and vaping — which makes people think they might as well continue smoking."

The proposal faces some procedural hurdles. It still must get the council's approval to make it to the agenda for a vote.