Around Washington state, cannabis shops are being required to hang signs warning customers of "severe lung injuries" and "deaths" associated with vaping.
Kevin Heiderich, a co-owner of one such shop, House of Cannabis in Tacoma, Wash., believes the government response to vaping illnesses should focus on the black market.
"Something has just changed and no one really knows what it is," he says.
Still, Heiderich supports more rigorous testing so the regulated market is perceived as safer. This summer, his shops began contacting all their suppliers to verify what's in their products.
He acknowledges some "bad actors" could be selling products on the legal market in Washington.
"Hopefully, that is the exception to the rule, and any regulation that does come down puts an end to those sort of business practices," he says. "We don't need those people in the market."
Health officials nationwide are still puzzling over why some who vape are coming down with a severe respiratory illness and, in some cases, dying. So far, the Centers for Disease Control and Prevention's investigation has identified more than 1,600 cases, but has yet to pinpoint a lone cause that explains all cases.
Many cases have been traced back to vape cartridges filled with THC (the psychoactive ingredient in cannabis) — cartridges the users found on the black market. Some who have gotten ill were vaping both THC and nicotine, according to CDC reports. A smaller percentage report using only nicotine.
"The data do continue to point to THC-containing products as the source of the vast majority of individuals' lung injury," Dr. Anne Schuchat, the CDC's principal deputy director, told reporters at a press briefing Friday.
"There are continuing cases that do not report that history," she said, "but I'd like to stress that we don't know what the risky material or substance is, and THC may be a marker for a way that cartridges are prepared or the way devices are producing harm."
Schuchat said it remains to be seen if that is also happening with devices that contain nicotine — not just THC.
"We are seeing the THC as a marker for products that are risky," she said, "but at this time, because of the continued presence of cases that only report exclusive nicotine-containing e-cigarette or vaping product use, we feel that it is very important for people to consider refraining from use of any kind of e-cigarette."
In response to the CDC's ongoing investigation, a handful of states have banned certain vaping products. States where recreational marijuana is legal are also taking a second look at their regulations.
Massachusetts moved to temporarily stop the sale of all vaping products. Oregon and Washington have enacted emergency bans on flavored vaping products. (A judge in Oregon has since put a stay on the temporary ban of flavored nicotine vapes, but allowed the ban on flavored vapes containing THC to stand.)
Some cases of lung injury in Washington and Oregon may be linked to products of the regulated cannabis market, according to local health agencies, raising questions about the safeguards for consumers who vape legal products.
"I could barely breathe"
Charles Wilcoxen, a police officer for the Puyallup Tribe in Washington state, turned to vaping cannabis nearly two years ago. The 44-year-old U.S. Army veteran says he assumed it was a safer alternative to smoking the plant.
Wilcoxen says he would buy the vape cartridges from Washington's legal marijuana shops and use them on his off-duty days to relieve stress.
There was nothing unusual about his vaping routine in September he says — "I used the same device and the same cartridges as I had in the past."
But this time Wilcoxen very quickly became sick. Shortly after vaping, he began wheezing heavily. Soon he was nauseated and running a fever.
"I just felt horrible," he remembers. "I tried to get through the weekend and tough it out."
At first, Wilcoxen thought it could be the flu. But then he started to suspect his illness might be related to his vaping. When Wilcoxen woke up one morning and could barely breathe, he decided to go to the emergency room.
"Literally, I would take five steps and have to hunch over and try to catch my breath," he says.
He ended up spending three days in the hospital.
Doctors found a strange build-up in his lungs and sent it for analysis. The results came back positive for lipoid pneumonia — a rare respiratory illness caused by oils or fats entering the lungs. It's one of the vaping-related conditions researchers have identified in others hospitalized in recent months.
Wilcoxen is still recovering and has decided to sue.
His lawsuit alleges that defects in the vaping products led to his illness. He's going after six companies that have a role in manufacturing or distributing the cartridges or the vaping device.
"Buy something off the black market, you are taking your chances," says Mark Lindquist, Wilcoxen's attorney. But customers who buy their vape products from a state-licensed store, he says, should be able to count on getting a safe product.
States look to new rules
Testing standards for cannabis vary across the legalized market in the U.S.
The state of Washington requires that vape products sold in stores be checked for, among others things, potency, toxins and residual solvents used in the extraction process. Some states, including California, go even further and mandate testing for other substances, such as pesticides.
These regulations, however, don't necessarily require checking for other potentially harmful chemicals that sometimes find their way into vape cartridges on the black market and could, conceivably, turn up in legal cartridges, too.
The ongoing investigation into vaping-related illnesses has revealed that illicit THC cartridges sometimes contain so-called "cutting agents" like Vitamin E acetate, which isn't safe to inhale.
Shannon Stevens, laboratory director for Confidence Analytics, which has a state license to test cannabis products in Washington, says a cutting agent is typically used to dilute the THC oil in the black market supply.
But state labs in Washington aren't necessarily looking for Vitamin E acetate.
"There is no requirement to test for any sort of cutting agent," Stevens says.
In recent months, more customers have been asking her laboratory to test for Vitamin E, out of concern for its possible role in the vaping-illness outbreak.
Stevens says she'd be "surprised" to discover Vitamin E in one of the products sold in Washington's legal retail stores. "But I definitely wouldn't exclude the possibility," she says, "because there are no checks on that right now."
Washington state bans flavors
In an effort to identify harmful chemicals, Washington state regulators are collecting information from cannabis companies that make vaping products.
In the meantime, the Washington State Board of Health recently passed a four-month emergency ban on flavored vaping products, which applies to both nicotine and THC.
"We aren't waiting for Big Tobacco to tell us what is in their products," Gov. Jay Inslee said, in announcing his executive order to prohibit the sale of certain vaping products.
Inslee's administration is framing the outbreak as yet another symptom of the rise in youth vaping.
Dr. Kathy Lofy, the state health officer for Washington, says a ban on flavored products will discourage young people from vaping in the first place.
"While we don't know yet exactly what is causing severe lung injury, we did like the option of banning flavors because we know the youth are very attracted to flavors," she says.
But the state's public health leaders also acknowledge the ban isn't necessarily a remedy to the current outbreak of illnesses.
"We are not saying that the flavors are what are causing this current lung injury or illness," said Washington's Secretary of Health John Wiesman before voting in favor of the ban. "We obviously don't yet know what that is."
Before Washington passed its ban, many from the vape industry criticized the move as heavy-handed and misguided. And some public health experts warn the ban could backfire.
"There is this risk when you ban something [legal] that people will be driven to the black market," says Ziva Cooper, director of the UCLA Cannabis Research Initiative.
Cooper says the regulated cannabis market is already fraught with problems. People walk into a cannabis shop with neatly packaged products and believe everything has undergone rigorous safety testing, she says.
"They think they can trust what's on the labels," says Cooper, "but the truth is the labels don't necessarily accurately portray what's actually in the products."
She says it doesn't help that the public health messaging is all over the place — often lumping together cannabis and nicotine products.
Given all the unknowns about the vaping illnesses, the CDC continues to issue broad warnings about the risks of vaping.
Schuchat says vapers can't assume that some states have a better handle on quality than other states.
"Whether the substances that are in products that are completely unregulated by the states are riskier than the products that are regulated by the states," Schuchat recently told reporters, "I don't think we have good data either way."
This story is part of NPR's partnership with Kaiser Health News, a nonprofit, editorially independent program of the Kaiser Family Foundation. KHN is not affiliated with Kaiser Permanente.
Will Stone is a freelance reporter based in Seattle. He is on Twitter at @wstonereports.
SCOTT SIMON, HOST:
The Centers for Disease Control say most of the cases of respiratory illness from vaping are linked to products containing THC, the psychoactive ingredient in cannabis. People have gotten sick even in states where marijuana sales are legal and where marijuana must undergo some quality testing. Will Stone brings us the story of a man who got sick in Washington State, where recreational pot has been sold since 2014.
WILL STONE, BYLINE: About two years ago, Charles Wilcoxen turned to vaping marijuana, believing it would be better than smoking it.
CHARLES WILCOXEN: I felt that vaping was a safer alternative. It was - I truly believed that.
STONE: Wilcoxen would buy the vape cartridges from Washington's legal marijuana shops, where they're tested for things like mold. The 44-year-old is an Army veteran and runner, and he was in good health until one day last month. After vaping, Wilcoxen became sick very quickly. He started wheezing. Soon he was nauseous and running a fever.
WILCOXEN: I felt miserable. You know, it was, like, flu-like symptoms.
STONE: After a few days he began to wonder, could it be the vape?
WILCOXEN: And I used the same device, same cartridges that I'd been using in the past.
STONE: The next day, he woke up and could barely breathe.
WILCOXEN: Literally I would take five steps and have to hunch over and try to catch my breath.
STONE: Wilcoxen ended up spending three days in the hospital. Doctors found buildup in his lungs and sent it for tests.
WILCOXEN: It all came back positive results for lipoid pneumonia, which was indicative for - from the vaping. You know, it's where it came from.
STONE: Lipoid pneumonia, the same respiratory condition identified in some others who have fallen ill after vaping. Wilcoxen decided to sue. He's going after six companies. All have a role in manufacturing or distributing the vaping device or the cartridges that contain a liquid form of THC, the psychoactive ingredient in marijuana. Public health agencies have traced many cases of vaping illnesses back to THC products, some bought on the black market.
Testing has shown those illicit THC cartridges can contain cutting agents like vitamin E acetate, which isn't safe to inhale. But Wilcoxen says he only went to state-licensed stores. Washington requires that labs test marijuana for potency and certain contaminants, but not other chemicals added to the liquid THC.
SHANNON STEVENS: There is no requirement to test for any sort of cutting agent.
STONE: Shannon Stevens is laboratory director for Confidence Analytics, which has a state license to test cannabis products in Washington.
STEVENS: I would be surprised to learn that an illegal product in our retail stores had been identified as having been cut like this, but I definitely wouldn't exclude the possibility.
STONE: Like other states, Washington is trying to identify what harmful chemicals might be in vaping products. In the meantime, the state has passed a four-month emergency ban on flavored vaping products. It applies to both nicotine and THC. Dr. Kathy Lofy is the state health officer for Washington.
KATHY LOFY: While we don't yet know exactly what's causing severe lung injury, we did like the option of banning flavors because we know that, you know, youth are very attracted to the flavors.
STONE: But the state's public health leaders acknowledged that prohibiting flavors won't necessarily stop the current outbreak of illnesses. Ziva Cooper directs the UCLA Cannabis Research Initiative.
ZIVA COOPER: There is this risk when you ban something that people will be driven to the black market.
STONE: Even in states where cannabis is regulated, Cooper says the market is fraught with problems. People are walking into stores and buying neatly packaged products that look legit.
COOPER: They think that they can trust what's on the labels. But the truth is is that the labels don't necessarily accurately portray what's actually in the products.
STONE: For now, the Centers for Disease Control and Prevention is keeping warnings about vaping brought. At a recent congressional hearing, CDC's deputy director Dr. Anne Schuchat said while most cases are linked to the black market, her agency doesn't yet have a clear picture of the risks where marijuana is legal.
ANNE SCHUCHAT: Whether the substances that are in products that are completely unregulated by the states are riskier than the products that are regulated by the states, I don't think we have good data either way.
STONE: Until more is known, those who vape need to realize that no matter where they, live the safety regulations vary. And testing, even in states where pot is legal, has not necessarily caught up with whatever might be causing the current outbreak of illness. For NPR News, I'm Will Stone in Seattle.
SIMON: And that story comes to us from NPR's reporting partnership with Kaiser Health News.
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