Fifty-five Democratic U.S. House members sent a letter to the Trump Administration on Thursday asking for removal of all flavored e-cigarettes from the market.

“The FDA reports that 97% of youth e-cigarette users vaped a flavored e-cigarette and a large share of children that began using these products did so because of their appealing flavors,” wrote the lawmakers. U.S. Rep. Diana DeGette was one of the lead authors, and U.S. Rep. Jason Crow was also a signatory.

The letter came in response to the administration’s announcement in early January that it will prioritize enforcement against the sale of most flavored vape cartridges. All electronic cigarettes are currently not on the market legally, but the U.S. Food & Drug Administration is using its enforcement discretion to permit the continued distribution. It has largely chosen to focus on companies’ marketing and sales practices.

The policy was a reversal from the original position of the White House. In September, the FDA announced plans to go further than the eventual guidelines would allow.

“The Trump Administration is making it clear that we intend to clear the market of flavored e-cigarettes,” said U.S. Secretary of Health and Human Services Alex Azar at the time.

Lawmakers cited that e-cigarette use among adolescents has risen, and can affect brain development.

“We are deeply alarmed that this policy exempts open tank-based products, disposable flavored e-cigarettes and certain flavored e-cigarette cartridges, including menthol and even tobacco,” they wrote. “These exemptions are all but certain to increase the popularity of refillable flavor pod systems”.