Leafly investigation: Lax THC vape rules still allow toxins into your lungs

Legal THC vape rules need tightening: Here’s why. | Leafly


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In 2019 and 2020, vaping-associated lung injuries killed 68 people and injured 2,807 across the United States. As reported by Leafly and later confirmed by officials at the Centers for Disease Control and Prevention (CDC), those injuries and deaths were almost exclusively associated with unlicensed THC vape cartridges purchased from the illicit market.

At the heart of the health crisis was a relatively new vape cartridge additive known as vitamin E acetate. Unlicensed cartridge manufacturers were using the substance, a common ingredient in beard cream, to thicken the cartridge oil and boost profit margins.

After the poisonings, officials at the CDC said the number one thing state cannabis regulators could do to protect public health was ensure that “chemicals of concern” like vitamin E acetate did not enter the state-licensed THC vape cartridge supply.

As of early 2021, cannabis regulators have not done that.

Leafly’s comprehensive review of THC vape cartridge rules in the 15 legal cannabis states found loopholes where chemicals of concern can get in.

A Leafly investigation into current and forthcoming regulations around THC vape cartridges in the 15 legal cannabis states reveals that more than a year after the vape lung (also known as EVALI or VAPI) crisis, a few states have banned vitamin E oil, but not a single state upgraded its THC vape cartridge testing requirements up to the standard currently required for all nicotine vape cartridges in Europe and Canada.

State cannabis regulators have generally done a great job of protecting the health of consumers by requiring tests for toxins like pesticides, residual solvents, heavy metals, mold, and bacteria. Manufacturers are also required to test and disclose the exact potency of every product on the label.

But sometime around late 2018, THC vape cartridges escaped the bounds of those safeguards. A new wave of novel cartridge oil additives, thickeners, thinners, diluents, and artificial flavors began flooding the market. The new additives were mostly limited to illicit-market vape carts, but a few seeped into the legal regulated market as well.

Those new additives included:

  • Vitamin E acetate, aka beard cream oil
  • Squalene, a shark liver oil substance
  • Thousands of food flavorings not approved for inhalation

What kept these toxins from flooding into the legal THC vape supply? Only the good conscience of many licensed vape cartridge manufacturers—and a bit of luck. Nothing in the regulatory system of any state would have prohibited most of the new wave of additives.

Even today, the existing patchwork of state rules—with their yawning safety gaps and a total absence of federal oversight—has experts throwing up their hands.

Sickened lungs show up as cloudy on the left x-ray, and clear after treatment of one suspected VAPI patient in Utah. (Courtesy University of Utah)
Certain vape additives are associated with lung injury, which shows up as cloudy on the left x-ray, and clear after treatment of one suspected VAPI patient in Utah. (Courtesy University of Utah)

Vape chemistry and regulations expert David Heldreth Jr. stepped down as the Chief Science Officer of a vape flavoring company. “It’s painful,” he told Leafly. “It’s one of those things where the industry just popped up and grew so quickly, it’s really difficult to keep up with what people innovate.”

CannaCraft, California’s biggest vape maker, forbids non-cannabis ingredients in its products, citing a lack of safety data. But the only thing keeping the company from adding mystery flavorings is the integrity of company officials. Many in the industry are doing it right. Others have less scruples. Consumers have few ways to tell.

“I think we do a lot of things well, but there’s certainly room for improvement,” said Matthew Elmes, a molecular biologist and Director of Scientific Affairs for CannaCraft. “There are so many things that aren’t tested for, and we don’t know, as consumers, what’s going on there.”

Leafly’s comprehensive review of THC vape cartridge rules in the 15 legal cannabis states found loopholes where those chemicals can get in.

Those gaps exist in three major categories: emissions testing, known toxins, and mystery additives.

Safety gap 1: emissions testing

On Nov. 8, the Centers for Disease Control and Prevention confirmed Aug. 30 Leafly findings of a new, toxic cutting agent in the illicit THC vape cart supply chain—vitamin E acetate. Above, a woman using a vaping device in Mayfield Heights, Ohio (Tony Dejak/AP)
Above, a woman using a vaping device in Mayfield Heights, Ohio (Tony Dejak/AP)

None of the 15 adult-use states and the 20-plus medical states currently requires manufacturers to test vapor coming out of a vape pen. This is known as “emissions testing,” and it’s required of all nicotine vaping products in Europe and Canada.

Here’s why it matters. Experts said emissions tests can reveal heavy metals found not in the raw cannabis oil but in vapor from shoddy devices, or toxins from burning unsafe mixtures.

Vaping expert Arnaud Dumas de Rauly, chairman of the International Standards Organization (ISO) committee on vapor products, told Leafly, “Every state should be doing emissions testing—100%.”

“I personally would feel the safest seeing those [emissions] results,” said CannaCraft’s Matt Elmes. “A lot of the cheaper hardware or pens that operate at higher temperatures certainly have the potential to leech extra heavy metals into that oil upon use.”

“We’re talking about consumer safety. Without it, our industry will just die.”

Arnaud Dumas de Rauly, chairman of the International Standards Organization (ISO) committee on vapor products

“We’re talking about consumer safety,” added Arnaud Dumas de Rauly. “Without it, our industry will just die.”

Emissions testing technology already exists. Europe and Canada require it. What’s lacking in the United States? The political interest and will to adopt a testing standard.

That’s starting to change—but far too slowly. Colorado will become the first state to mandate emissions testing, next year in 2022.

No other state has a THC vape cartridge emissions testing requirement in the pipeline. Even in Colorado, millions of cartridges will sell between now and 2022.

Safety gap 2: known toxins

vape lung injury, dangers of vaping cannabis, marijuana vaping illness
Cannabis extract can be diluted with a variety of clear, odorless, heavy oils dangerous to inhale, like vitamin E acetate, pictured above. (Courtesy of Lauren Bishop/CDC)

The world’s largest legal cannabis market, California, never explicitly banned vitamin E acetate, which caused the vape injury outbreak in 2019 and 2020. The nation’s biggest industry trade group, the National Cannabis Industry Association (NCIA), recommends a complete ban of the substance. Both regulated manufacturers and illicit ones seem to have stopped using it when VAPI hit.

Washington, Colorado, and Oregon have banned the substance. But other legal states have not followed.

In California, state regulators only require manufacturers to disclose that a vape cartridge contains vitamin E acetate. That’s like allowing Coors to add a little bathtub gin to every beer as long as they disclose its presence on the label.

Safety gap 3: mystery additives and flavors

The FDA never approved a flavor for use on lung tissue. But it’s a business anyway. Above, a Los Angeles storefront advertises terpenes. (David Downs/Leafly File Photo)

Most state cannabis regulations never mention the words “additive” or “flavoring,” two of the biggest vectors of harm in vape pens uncovered in last year’s lung injury outbreak.

Nine years after legalizing cannabis, officials in Washington state will finally—this month—begin taking public comment on the definition of a “flavor,” and create a process for banning toxins from vape cartridges.

National Cannabis Industry Association media relations director Morgan Fox endorsed the idea, saying it’s “appropriate and useful” for all states to create a banned additives list—as well as a rigorous and transparent process to decide which substances are added or removed from the list.

Potential solutions

Many experts say state vape safety rules need upgrades to a new baseline founded upon the precautionary principle. That is: Anything non-cannabis gets prohibited unless and until it’s proven safe for human inhalation.

Rules updates should happen before—not after—the next outbreak of lung injuries. This is about fortifying the legal markets amid the collapse of prohibition.

“I think banning entirely, or at least limiting, the types of diluents or additives in inhalable oil absolutely should be discussed in the future regulations,” said CannaCraft’s Elmes.

Other experts worry about the unintended consequences of bans. Dramatic overreach, they say, could drive millions of consumers to the illicit market, which contains more and higher levels of inhaled toxins.

Dr. Jahan Marcu, editor in chief of the American Journal of Endocannabinoid Medicine, helped author the American Herbal Pharmacopoeia’s imprint on cannabis quality assurance. Marcu prefers a mix of bans, moratoriums, mandatory disclosures, and allowed additives, depending on the substance.

“We want to avoid going from a bad situation to a potentially worse situation,” Marcu said. “We need better data from products [currently] on the market.”

What consumers can do

Until state regulators get around to updating THC vape testing rules, there are a few basic steps consumers can take to minimize the risk of inhaling toxic additives.

Those include:

  • Purchase only from state-licensed cannabis stores.
  • Use only licensed brand products.
  • Avoid products with vague ingredients.
  • Look into a brand’s stated vape oil practices—it’s often posted on their website.
  • Ask your budtender hard questions about what’s in a vape cart, and how they know it. If they can’t answer, they’ll start asking hard questions of their suppliers. Consumer pressure works.

Shop smarter

Here’s How to Buy and Review Vape Carts

There are good high-quality vape pens out there. Here's some ways to identify them. (Leafly)
There are good high-quality vape pens out there. Here’s some ways to identify them. (Leafly)

“I’ve talked to a number of producers who refuse to use anything that’s not cannabis-derived,” said Morgan Fox, at the National Cannabis Industry Association, which published a white paper on vape safety rules in 2020. But it’s not easy to find out who those producers are when you’re standing at the merch counter with a line of customers behind you.

Be on the lookout for vague ingredients. Potentially dangerous or contaminated additives are sometimes labeled as “natural flavorings.”

The FDA never approved a “natural” “flavor” for use on lung tissue. Quite the opposite: exploratory research keeps finding new harms from inhaling additives and flavors.

Marcu, who co-founded a pro-cannabis consultancy, Marcu and Aurora, in Washington state, said he doesn’t use legal vape pens right now.

Oregrown is voluntarily recalling the remainder of the Viscosity batch: “Oregrown PAX Era D9 Elite” vaping products manufactured on or prior to August 31, 2019. Above, a "PAX Era" style "pod" disposable cartridge for vaping THC oil. (David Downs/Leafly)
The vape pen and pod-product category (shown above) has evolved faster than regulators ever imagined. (David Downs/Leafly)

“I don’t want to pooh-pooh anyone’s product,” he told Leafly. “But it seems to me that I do not trust most vape [cartridges] on the market unless the company has a good toxicologist on staff.”

Heldreth Jr., now-CEO of hemp food company Ziese Farms and biotech firm Panacea Plant Sciences, also said he’s not buying vapes in Washington.

“I don’t particularly buy them in general,” he said. “When I did, I was always the person that would use cannabis-only vape products.”

Consumers who want the smooth draw of vapor without any chance of unknown additives should try dry herb vaporizers like the Volcano or the Pax 3. This class of products vaporize cannabis flower, which undergoes required testing in legal markets. It’s super-safe. For example, the Volcano vaporizer has been used in FDA-approved trials.

“I fully agree with working within the plant,” said Dumas de Rauly.

Tomorrow, part 2 of our investigation details the chemicals of concern to different state regulators.

Wednesday, part 3 explains what the federal government is doing, and the vape safety loopholes in each legalization state.

David Downs's Bio Image

David Downs

David Downs directs news and lifestyle coverage as the California Bureau Chief for Leafly.com. He’s written for WIRED, Rolling Stone and Billboard, and is the former cannabis editor of the San Francisco Chronicle, as well as the author of several cannabis books including ‘Marijuana Harvest’ by Ed Rosenthal and David Downs. He co-hosts The Hash podcast. TW: @davidrdowns | IG @daviddowns

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