The US Food and Drug Administration is taking steps to stop the sale of flavored, cartridge-based e-cigarettes, which are widely used by children. In a final policy announced Jan. 2, the agency says that in 30 days it will begin enforcement actions against companies that make, distribute, or sell many unauthorized e-cigarette products. The policy does not apply to products that contain tobacco or menthol flavors, or any flavors used in e-cigarette devices with refillable tanks. The action is intended to address the epidemic of youth vaping in the US. It does not address the thousands of recent cases of serious vaping lung illnesses, which health officials have linked to contaminated vaping products containing tetrahydrocannabinol (THC), the psychoactive ingredient in cannabis. A 2019 survey suggests that nearly 1 million youths in the US vape nicotine e-cigarettes daily and that they favor products with fruit or mint flavors. Surveys also suggest that young people primarily vape cartridge-based devices, which are easy to use and conceal. The FDA’s policy attempts to rein in such vaping while still allowing some flavored e-cigarette products to stay on the market for adults to use to quit smoking tobacco.