Presidential adviser Kellyanne Conway suggested yesterday that the Food and Drug Administration (FDA) may decide to exempt vape shops from its pending ban on flavored e-cigarettes. There is a certain logic to that, since those shops, unlike other retailers, do not admit minors, and curbing underage vaping is the rationale for the ban. But it's not clear that approach would be legal. Furthermore, Conway's assertion that the FDA "do[es] not have jurisdiction over vaping and vape shops" is puzzling, given how the agency understands its regulatory authority.

The FDA derives its authority over vaping products from the Family Smoking Prevention and Tobacco Control Act, which allows it to regulate "any product made or derived from tobacco that is intended for human consumption, including any component, part, or accessory of a tobacco product." Although e-cigarettes do not contain tobacco, they typically deliver nicotine that is derived from tobacco, and in 2010 the U.S. Court of Appeals for the D.C. Circuit agreed that is enough to make them subject to FDA regulation.

But the Tobacco Control Act also says the FDA may not "prohibit the sale of any tobacco product in face-to-face transactions by a specific category of retail outlets." On its face, that provision means the FDA may not ban sales of flavored vaping products in convenience stores while allowing them in vape shops.

That is how the National Association of Convenience Stores reads the law. "The Tobacco Control Act is clear that the FDA can't discriminate against one type of retail outlet, and that's what they're trying to do here," Doug Kantor, a lawyer for the trade group, told The New York Times when the issue came up last year. "There is a very good chance this will end up in litigation."

Conway seems to be suggesting a way around that obstacle by arguing that the FDA simply does not have jurisdiction over open-system vaporizers (as opposed to cartridge-based products such as Juul) and the e-liquids used in them. But that is plainly inconsistent with the way the FDA has interpreted its regulatory authority under the Tobacco Control Act.

According to the FDA, any device that can be used to deliver tobacco-derived nicotine qualifies as a tobacco product, and so do the e-liquids used with such devices. The agency says even a nicotine-free e-liquid (NFL) can count as a "component or part" of a tobacco product. "Assuming an NFL is not made or derived from tobacco," the FDA says, it is still subject to the agency's e-cigarette regulations "if it is 'intended or reasonably expected' either '(1) To alter or affect [a] tobacco product's performance, composition, constituents, or characteristics; or (2) To be used with or for the human consumption of a tobacco product; and is not an accessory.'" Hence "an NFL that is intended or reasonably expected to be mixed with liquid nicotine would qualify as a 'component or part.'"

Contrary to Conway's comments, the FDA plainly believes it does "have jurisdiction over vaping and vape shops," which is consistent with the interpretation upheld by the D.C. Circuit. And if open-system vaping devices and the e-liquids used in them are indeed tobacco products subject to FDA regulation, the Tobacco Control Act seems to preclude a flavor ban that is selectively applied to "a specific category of retail outlets."

Perhaps what the FDA plans to do is ban flavored cartridges everywhere, based on the premise that Juul-like products are the ones preferred by teenaged vapers, while allowing flavored e-liquids used in open-system devices. But that distinction would not draw a line between different categories of retailers, and it would not rely on a new understanding of the agency's authority.

Last year the FDA proposed a rule that would allow sales of flavored e-liquids in stores that do not admit minors (i.e., vape shops) or that put those products in "a section" that "adequately prevents entry of persons under the age of 18," as long as the products "are not visible or accessible to persons under the age of 18 at any time." Although that approach notionally allows convenience stores to continue selling flavored e-liquids, the segregation requirement probably would be prohibitive in practice. It is therefore not clear such a rule would pass muster under the Tobacco Control Act. While allowing adults to continue buying flavored e-liquids from some sources is certainly preferable to a blanket ban, I'm not sure how that policy can be reconciled with the law.