On Monday, Sens. Dick Durbin (D-IL) and Lisa Murkowski (R-AK) announced that they plan to introduce a bill this week that will regulate e-cigarette flavorings and ban flavors in cigars. Experts say that the proposed legislation is a step toward keeping young people from trying e-cigarettes, but it may not get very far in Congress as the midterms approach.

The awkwardly named “Stopping Appealing Flavors in E-Cigarettes for Kids” (or SAFE Kids) act would require vape manufacturers to prove that their flavorings aren’t harmful, don’t tempt kids into using nicotine, and actually help adults quit, the announcement says. If they don’t, the products wouldn’t be allowed to stay on the market. It’s the latest shot in Durbin’s ongoing campaign to keep young people from using vapes, which he’s called “candy-flavored poisons” in the past, according to Roll Call.

“I am convinced that e-cigarettes represent the ‘re-invention of smoking,’ cooked up by Big Tobacco to hook a new generation,” Durbin said in a statement on Monday. That recipe includes “flavors that shamelessly appeal to kids,” Durbin said.

This isn’t the first time that regulators have eyed flavorings in tobacco products. In 2009, the Food and Drug Administration banned all flavors except menthol in combustible cigarettes. The ban worked: adolescents were 17 percent less likely to become cigarette smokers after it was enacted, according to a study published in the American Journal of Preventive Medicine. But the FDA didn’t have the power to regulate cigars or e-cigarettes until 2016, and those products fell through the cracks of the flavoring ban. Some local governments, like the city of San Francisco, have recently banned the sale of all flavored tobacco, including e-cigarette liquids, but regulation at the federal level has moved more slowly.

The FDA is starting to investigate regulating e-cigarette flavorings, too. In March, the agency began soliciting public comments about things like the safety of e-cigarette flavors and whether they encourage adults to quit smoking cigarettes or adolescents to start vaping. “The troubling reality is that e-cigarettes are the most commonly used tobacco product among middle and high school students, and flavors are identified as one of the top three reasons for use,” FDA commissioner Scott Gottlieb said in a statement at the time. But for now, the agency is just gathering information: there’s no timeline for crafting new regulation.

Durbin and other public health experts are worried that kids will be attracted to vaping because of the flavors and will get hooked because of the nicotine. “Tobacco is a horrible-tasting product. It’s something that you don’t just use and like immediately,” says Ilana Knopf, director of the Public Health and Tobacco Policy Center at Northeastern University. “So flavors are really starter products,” she says — kind of like adding a spoonful of sugar to medicine.

It’s true that people don’t generally start vaping with e-liquids flavored to taste like cigarettes, according to a 2017 study published in the journal Preventive Medicine Reports. While both adolescents and adults listed fruits as their favorite vape flavors in a paper published in the journal PLOS One, adults’ second and third choices were tobacco and menthol. Kids, no surprise, preferred sweet-tasting candy, dessert, and vanilla flavors, the study says. The more flavors adolescents liked, the more they vaped — a trend that didn’t apply to the adults. “That suggests that flavors or flavor preferences might play a more important role in driving adolescent vaping than for adults,” says Meghan Morean, a psychology professor at Oberlin College and a co-author of the study.

The other issue is whether flavorings are safe. The FDA considers many of the flavorings in e-liquids safe to eat, but we don’t actually know if they’re safe to inhale, according to a massive review of vaping studies conducted by the National Academies of Sciences, Engineering, and Medicine. Some flavor additives have been linked to a condition called popcorn lung, and others were found to cause lung inflammation in cells and animal models. That doesn’t mean that these flavorings will necessarily do the same things in human lungs, but it does mean that there needs to be more research.

Durbin and Murkowski’s proposed bill would give vape manufacturers a year to hand over evidence that their flavorings are safe, that they help adults kick their cigarette habit, and that they don’t tempt kids. But Kathleen Hoke, a professor specializing in public health law at the University of Maryland, isn’t optimistic that Congress will do anything with the proposed legislation. With midterms coming up and a Republican-controlled Congress, they’re “less likely to be interested in a trade-restrictive bill,” she says.

But Hoke doesn’t think that this is a wasted effort either. “It starts the conversation, and I think it pokes the FDA.” And maybe other state and local governments will be inspired to come up with policies of their own in the meantime, she says. “This sends a strong message.”