The mystery of the outbreak of vaping-related lung illnesses is still not solved.
But investigators in Illinois and Wisconsin have found some clues, they announced Friday in a press briefing.
Investigators in these two states conducted detailed interviews with 86 patients — mostly young men — and 66% said they had vaped THC products labeled as Dank Vapes. THC is the psychoactive ingredient in cannabis.
What are Dank Vapes and how could they be fueling the outbreak?
"Dank Vapes appears to be the most prominent in a class of largely counterfeit brands, with common packaging that is easily available online and that is used by distributors to market THC-containing cartridges," said a report from state investigators published Friday by the Centers for Disease Control and Prevention.
The CDC has been warning since the outbreak began about the risks of buying products "off the street," and Friday's update highlighted the risks of the black market. Sometimes young consumers don't even realize that they're buying unregulated or illicit products.
"THC-based products were most often acquired from informal sources such as down the street from friends or from a dealer," said Jennifer Layden of the Illinois Department of Public Health at the press briefing.
Around the country, law enforcement is trying to crack down on black market dealers. In Wisconsin earlier this month, two brothers were arrested for allegedly running a large THC vape ring.
And earlier this week, police in Waynesboro, Va., arrested three men and recovered more than 1,000 vape cartridges that were labeled as containing a 90% THC oil mixture.
"They're labeled Dank Vapes," Capt. Mike Martin of the Waynesboro Police Department says. "They appear commercially packaged, and there are a variety of different flavors."
The mixture appears as "a standard-looking brownish oil. ... It has the consistency of ... maybe, like a motor oil," Martin says.
"We've never seen a haul like this," Martin says. He estimates they recovered about $35,000 worth of vaping product. "They were selling these [on] the street."
One difficultly in unraveling this outbreak is that many of the patients around the country who have gotten sick acknowledge using both THC and nicotine vaping products and have used a wide variety of brands and products. In fact, the 86 patients in Wisconsin and Illinois reported using 234 different products.
Nonetheless, investigators now seem more focused on the role THC may be playing in this outbreak, since the majority of the people who have become ill around the country reported using THC or both THC and nicotine, according to a CDC report published Friday. And the CDC updated its warning against vaping to emphasize the risk of THC products: "CDC recommends people consider refraining from using e-cigarette, or vaping, products, particularly those containing THC," the CDC's Anne Schuchat said during a telebriefing Friday.
For people who are unsuspecting, black market products like Dank Vapes can be deceptive.
"Dank Vapes sounds like a cool name, it sounds like a cool product and it looks like legitimate packaging," says Jeffrey Kahn, who operates a medical marijuana dispensary in Washington, D.C. But, he says, unlike the regulated products he sells, you don't necessarily know what's in black market products. "If one or two or hundreds of people are unscrupulously filling them with dangerous material, then people could suffer," he adds.