In the latest trouble for the vaping industry, the Federal Trade Commission announced Thursday that it has opened an investigation into the marketing practices of six e-cigarette manufacturers.

The companies are Fontem US, a subsidiary of Imperial Brands; Juul Labs Inc., part-owned by Altria; Logic Technology Development LLC; NJOY LLC; Nu Mark LLC and R.J. Reynolds Vapor Co. 

The FTC is demanding the companies to provide it with written reports and data files "concerning the sales, practices and methods of advertising," in their vaping products from 2015 through 2018. The agency wants to see whether the companies targeted minors in that period, after a huge increase in e-cigarette popularity in recent years among young people was reported by the U.S. surgeon general as well as a rising number of reports of adverse health effects among users of vaping products.

As of Oct. 1, 1,080 lung injury cases associated with using e-cigarette or vaping products had been reported to the Centers for Disease Control and Prevention from 48 states and one U.S. territory, with 18 confirmed deaths, according to a CDC release posted on Thursday.

The commission is demanding annual data on sales and giveaways of e-cigarettes and liquids,  the characteristics of products, including their flavors; the amount of money companies spent on promotion and product placement and websites and social media accounts; the money they spent on ads and affiliate programs, influencer marketing and college campus promotions, among other things.

Gregory Conley, an attorney who is a spokesman for the American Vaping Association, a nonprofit advocacy group based in Connecticut, said: "The FTC is unlikely to learn anything new from this investigation, as multiple state attorneys general, the FDA and Congress have all thoroughly examined the marketing practices of Juul. As for the other five companies, none of them has anything to worry about as all of their past marketing has been largely unobjectionable with some minor exceptions that are unlikely to rise to the level that would allow for the FTC to take enforcement action against anyone." 

The FTC probe comes as the Food and Drug Administration, state attorneys general and cities  are also ramping up investigations and enacting restrictions on the marketing of e-cigarettes and other vaping products amid a rising number of users and increased reports of illnesses.

In early September, the FDA sent a letter to the chief executive officer and chief legal officer Jerry Masoudi demanding the company amend its advertising statements, including that its products were "much safer than cigarettes." Juul CEO Kevin Burns stepped down from office on Sept. 25 amid criticism and announced it would cease advertising. 

Also last month, citing the regulatory challenges, Walmart Inc. announced it would cease selling e-cigarettes and vaping products at its Walmart and Sam's Club stores, a decision that elicited criticism from the American Vaping Association because the stores continue to sell combustible tobacco products. Some of the illnesses reported have been associated with vaping of cannabis products as well as nicotine products.