A group of senators petitioned chief executives from top convenience retailers earlier this week to end the sale of illegal flavored vapes, reported the New York Times.

According to the Times article, the availability of “e-cigarettes in vivid colors and candy flavors that attract young people” poses a public health threat, the senators wrote in letters addressed to chief executives of several convenience retailing companies. The FDA has previously issued warnings to retailers to stop selling vape products targeted toward young people, including ones with cartoon themes.

The FDA has previously issued warnings about sales of unauthorized brands like Elf Bar, E.B. Design and Funky Republic, and selling unapproved products can result in fines for retailers or stop orders on selling tobacco products. The FDA has only approved 23 vaping products and has so far only authorized tobacco-flavored products, causing confusion among retailers about what they can and cannot sell.

“We have asked FDA numerous times for complete information about what can—and cannot—be sold in stores and they have declined to provide it,” Jeff Lenard, NACS vice president of strategic initiatives, told the New York Times. “It is long past time for FDA to provide that clarity and aggressively enforce the law.”

The letters were signed by Sens. Richard Durbin (D-IL), Ron Wyden (D-OR), Bernie Sanders (I-VT), Sherrod Brown (D-OH) and Richard Blumenthal (D-CT).

The Times noted that “levels of vaping among teenagers have fallen off drastically since a surge in popularity in 2019, when about 28 percent of high school students reported using e-cigarettes within the last month. That level fell to about 10 percent in a similar survey last year.”