State health officials said Friday that many patients sickened with mysterious lung injuries used black market marijuana vaping devices, offering the strongest clues so far into what might be making people sick.

Officials in Wisconsin and Illinois, the states that were the first to report cases, conducted in-depth interviews with 86 patients who said they used a wide range of e-cigarette products. The vast majority reported using illicit products containing THC, the psychoactive component of marijuana. The products were sold as prefilled vape cartridges — tiny disposable containers — and obtained from informal sources, officials said.

Nearly 70 percent of those patients said they used Dank Vapes cartridges, which appear to be predominant 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 with no obvious centralized production or distribution,” according to a report released by the Centers for Disease Control and Prevention on Friday.

Other brands identified by people with the lung injury include TKO, Off White, Moon Rocks, Chronic Carts and others. Industry experts said many THC products on the black market come from distributors who buy empty cartridges, fill them with THC mixtures, then purchase packaging with those brand labels.

Amid growing alarm about the lung illnesses and increases in youth-vaping rates, states are rushing to enact bans and restrictions on vaping products. On Friday, Washington state Gov. Jay Inslee (D) directed officials to impose an emergency ban on flavored vaping products — both nicotine and those containing THC. The governor told the state Board of Health to vote on the ban the next time it meets: Oct. 9. He also said he would push legislation to make the prohibition permanent.

Earlier this week, Rhode Island Gov. Gina Raimondo (D) signed an executive order barring the sale of flavored e-cigarettes throughout the state. State officials said the regulations would be effective for four months and could be extended for another two months. In Massachusetts, Gov. Charlie Baker (R) announced a four-month ban on all vaping products. Michigan and New York also are banning flavored-e-cigarette products.

Other states, including Virginia, are considering similar action.

On the federal level, the Food and Drug Administration is preparing a ban on flavors in nicotine e-cigarettes that was endorsed Sept. 11 by President Trump. Administration officials have said the ban would prohibit retail and online sales of flavored vaping products except for those that are tobacco-flavored. The order is expected to be finished in the next several weeks and go into effect 30 to 60 days after that. It would effectively remove flavored products from the marketplace until, and if, they get authorization from the FDA.

Both the state and federal actions could be delayed or blocked by legal challenges.

The Vapor Technology Association, a national trade group, along with two New York-based businesses, on Wednesday sued to try to stop the New York ban. “Banning flavors for vapor products, while leaving all flavored combustible products on shelves can only entice all users to smoke more,” said Tony Abboud, executive director of the group. In Michigan, the owner of a vape shop filed suit in a bid to block the flavor ban of Gov. Gretchen Whitmer (D).

In the marijuana industry, vaping cartridges are among the most popular items in both the legal and illicit markets, industry analysts have said.

Officials have said there is no single e-cigarette or vaping product, brand or specific substance that has been definitively linked to the growing national outbreak. Patients have used many kinds of products with a wide array of ingredients, some of which may have been mixed with potentially illicit substances, such as marijuana.

But the predominant use of prefilled THC-containing cartridges among patients who have been sickened “suggests that they play an important role” in causing the outbreak, the report said.

So far, 805 cases have been reported in 46 states and one U.S. territory, and at least 12 people have died.

Nationally, CDC officials said most of the people in the outbreak, or 77 percent, reported using THC-containing products or both THC and nicotine-containing products. That is the “most prominent link across all patients,” said Anne Schuchat, the CDC’s principal deputy director, during a briefing with reporters.

The data from Wisconsin and Illinois, which Schuchat described as “very compelling,” along with more information from a national snapshot of patients who fell ill, prompted the CDC to modify its warning Friday. The agency is urging people to consider refraining from using any e-cigarette products, especially those containing THC.

At the same time, even though evidence is “pointing to greater concern around THC-containing products,” Schuchat said officials don’t know whether that is the “only risky substance for lung injuries.”

“We are in the midst of a complex investigation that is encompassing nearly all states, and involves serious, life-threatening disease in young healthy people who have reported the use of a wide variety of substances and products,” Schuchat said.

Officials don’t know whether the illicit THC-containing vape cartridges associated with injuries in Wisconsin and Illinois are also linked to cases elsewhere. The FDA, which has been testing samples collected from patients, has not yet provided results on what substances were in the illicit cartridges collected from Wisconsin and Illinois patients. Patients obtained most of their illicit THC products from informal sources, including friends, illicit dealers or off the street, said Jennifer Layden, chief medical officer for Illinois’s health department.

Some teens who regularly use THC vape cartridges say they are aware of many counterfeit products. One Northern Virginia high school senior said he relies on his regular supplier, who graduated from the same high school, to buy products from legal dispensaries in the District, where recreational use is legal.

“I’ve smoked with him and smoked his stuff with him,” said the 17-year-old student, who spoke on the condition of anonymity to be candid.

Officials also don’t know whether there is a particular solvent or adulterant in one product, whether there are multiple products, or whether there are multiple brands involved, Schuchat said.

Officials have said they suspect the cause of the lung disease to be some kind of chemical exposure. One key focus of investigators is vitamin E oil, known as vitamin E acetate. Experts in the legal marijuana industry have said it has been used in the marijuana black market to stretch out THC oil that is used to fill vape cartridges. It is colorless and odorless, has similar viscosity to THC oil, and is much cheaper.

Vitamin E acetate, which is sold legally, is commonly used as a nutritional supplement and in skin-care products. It’s not harmful when ingested or applied to the skin. But health officials have warned it could be hazardous when inhaled, potentially causing the sorts of symptoms many patients have reported: cough, shortness of breath and chest pain.

Vitamin E acetate has been found in THC products taken from sickened patients and tested by state labs and the FDA’s forensic lab, officials have said.

The national investigation now includes a criminal probe by the FDA and the Drug Enforcement Administration. Officials are not pursuing individual vapers. But the FDA is investigating whether individuals are manufacturing or distributing illicit, adulterated vaping products that caused illness and death for personal profit. That would be considered a criminal act, officials said.

In a second report released Friday, CDC officials provided more detail about patients and what they reported vaping. More than two-thirds are male, with a median age of 23. Of 514 patients for whom officials had information on what they vaped, 395, or about 77 percent, said they used THC-containing products, with or without nicotine-containing products; 82, or 16 percent, said they exclusively used nicotine-containing products.

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