Walmart has announced its plans to stop selling e-cigarettes, just days after U.S. health officials confirmed a seventh vaping-related death.

The retail giant confirmed its decision in a memo published Friday by CNBC, signaling another major blow to the $2.6 billion vaping industry.

"Given the growing federal, state and local regulatory complexity and uncertainty regarding e-cigarettes, we plan to discontinue the sale of electronic nicotine delivery products at all Walmart and Sam’s Club U.S. locations," the company's memo read. "We will complete our exit after selling through current inventory."

On Thursday, the Centers for Disease Control and Prevention confirmed there were 530 lung injury cases related to e-cigarettes, aka vapes. About 16 percent of the cases involve individuals under the age 18, fueling concerns about underage tobacco use. Walmart announced earlier this year that it would no longer sell "fruit- and dessert-flavored electronic nicotine delivery systems," which have become popular among teens. The company also said it was raising the minimum age to purchase tobacco to 21.

The CDC has not linked the respiratory illnesses to a specific brand or substance, but said most of the affected patients have admitted to using vaping products containing THC, the main psychoactive compound found in cannabis; however, there are many other cases in which patients have reported using both THC and nicotine, while some have claimed to have only used nicotine-containing products. 

The CDC has urged the public to stop using e-cigarette products as the agency continues to investigate.

"Our laboratory is working closely with our federal and state partners to identify the products or substances that may be causing the illnesses and have received more than 120 samples from the states so far," acting FDA Commissioner Ned Sharpless said in a statement earlier this month. "The FDA is analyzing these for a broad range of chemicals but no one substance, including Vitamin E acetate, has been identified in all of the samples tested. Importantly, identifying any compounds present in the samples will be one piece of the puzzle but won’t necessarily answer questions about causality, which makes our ongoing work critical."