Several Democratic senators have signed a letter urging large retailers to stop selling tobacco products.

The letter comes months after the same senators sent a letter to Walgreens over the company’s alleged widespread sale of tobacco to children. Following the announcement by the Food and Drug Administration that flavored e-cigarettes will be banned, Walmart announced that it will cease e-cigarette flavor and device sales. The FDA announced earlier this year that several of America’s largest pharmacies have been illegally selling tobacco products. Now, the senators are concerned over the two public health crises striking the US. First, there’s the issue of minors becoming addicted to tobacco products at higher rates. Second, there’s the issue of hundreds of cases of lung disease being caused by vaping across the US, with eleven deaths recorded so far.

“These products—including e-cigarettes and the accompanying kid-friendly flavors—have never been proven safe. E-cigarettes have never been proven effective at helping people quit smoking. They do not have technology in place to ensure proper use. And they are being used primarily by children under the age of 18, in part because your company is either unwilling or unable to keep these products out of the hands of children who frequent your stores,” the Senators wrote in the letter.