The offerings at Fridley’s eCig & Supply Company store sound like something a kid might choose as a slushie or smoothie flavor on a hot summer day: Melon Mist; Blueberry Cream; Lemon Blast, and Papa Smurf’s Brother, a root beer and vanilla combo named for the iconic cartoon character.

Instead, these are among the more than 50 flavorings of “juice” — a liquid vaporized and inhaled through a pen-shaped device — that the store and others like it offer to those who want a nicotine hit without puffing on a traditional cigarette. Earlier this week, the number of customers streaming into the Fridley store attested to the rapidly growing popularity of e-cigarettes and “vaping.” (Since these devices produce a vapor, e-cigarette users say they “vape” instead of “smoke.”)

While e-cigarette sales are still a small fraction of the $80-billion-plus annual market for traditional tobacco cigarettes, sales of these essentially unregulated delivery devices for a highly addictive drug are skyrocketing, with 2012 sales of $300 million to $500 million expected to double in 2013, according to the Economist magazine. Neither regulators nor researchers assessing the potential health risks have kept up. That needs to change.

The U.S. Food and Drug Administration is still sitting on the sidelines when it comes to e-cigs. The agency has oversight of regular cigarettes and smokeless tobacco but not e-cigarettes unless they are sold along with a health claim. What that means is that minors in many states can buy e-cigs. Manufacturers may also advertise their often candy-flavored concoctions in ways that traditional cigarette companies are restricted from. An e-cigarette ban would go too far, given the uncertainties regarding their effects, but restrictions on e-cig sales and marketing to minors are common sense and overdue. Forty state attorneys general, including Minnesota’s Lori Swanson, recently sent a letter to the FDA demanding that the agency finally issue its expected but much-delayed regulations by the end of this month. An FDA spokesman this week declined to say if that deadline will be met.

States and cities also need to set parameters on e-cig use to protect public health while researchers determine the safety of their use — both for those who vape and those who may be exposed secondhand to the vapor.

While Minnesota does prohibit e-cig sales to those under 18, the state’s Clean Indoor Act does not restrict adult use. Legislators in 2014 need to ensure that the state’s smoke-free laws are up to date. Large tobacco companies, which are buying up e-cigarette makers, should not be able to exploit loopholes to get new Minnesotans hooked on nicotine and, potentially, their traditional tobacco products.

It’s unclear if e-cig users are more likely to eventually smoke cigarettes, but respected public-health experts, such as Minnesota Health Commissioner Dr. Ed Ehlinger, are concerned that e-cigs “normalize” smoking behaviors and may be a gateway to traditional tobacco use. This could potentially undo hard-won progress to cut smoking rates.

E-cig advocates, particularly those on social media, fairly point out that these products likely are safer than traditional smoking. It’s also clear from talking with customers at the Fridley store that e-cigs may have an important role to play in helping people quit tobacco. For Lisa Stegeman of Brooklyn Park, e-cigs are the only stop-­smoking product that has worked for her.

Still, data on e-cigs’ effectiveness is mixed, with a recent study in the Lancet showing no significant efficacy compared with a placebo. Data on the risks of long-term use is also inadequate. And with little oversight of the manufacturing of these products or the “juice,’’ who’s to say what’s in them? Not every proprietor is as conscientious as eCig & Supply Company’s Scott Huber, who uses only a reputable “juice” supplier based in Minnesota.

Medical research is also insufficient to determine the risk of secondhand exposure to the vapor. One study found that metal and silicate particles from e-cig aerosol were present in bystanders.

The Duluth City Council recently voted to prohibit e-cig use in public places, putting the city at the forefront of municipalities in Minnesota and elsewhere when it comes to e-cig safeguards. Duluth’s elected officials got it right. Medical researchers are only starting to determine e-cigs’ risks and potential benefits. Until these are known with more certainty, spaces free of cigarettes should be e-cig-free as well.