The US Food and Drug Administration (FDA) announced on its website that as of October 7, it had issued denial of acceptance (RTA) letters for synthetic nicotine (NTN) products in more than 889,000 Premarket Tobacco Product Applications (PMTA) that did not meet acceptance criteria.

The agency has accepted more than 1,600 applications, the vast majority of which are for e-cigarettes or vape products.

"While application review is ongoing, FDA remains vigilant in monitoring the market and will continue to use our compliance and enforcement resources to curb the illegal marketing of [non-tobacco nicotine] NTN products," the agency wrote. "To date, the FDA has issued more than 60 warning letters to manufacturers, including brands that are popular among young people, such as Puff Bar. Manufacturer warning letters include those whose products have been submitted but for which the agency has taken negative action."

The FDA also issued more than 300 warning letters to retailers for selling NTN products to minors and imposed civil penalties on two retailers for selling NTN products to minors.

"To date, the FDA has not approved any NTN products. As a result, all NTN products on the market are sold illegally and are at risk of FDA enforcement action, "the FDA said. "It is illegal for retailers or distributors to sell or distribute e-cigarettes that are not authorized by the FDA, and those who engage in such conduct are subject to FDA enforcement, such as forfeiture, injunctions, or civil penalties."