VIDEOS

Follow Us

What we still don’t know about the chemical culprit in vaping illnesses

Months before the novel coronavirus took hold of the globe in late 2019, clusters of patients began appearing in emergency rooms throughout the US with a mysterious lung disease. Investigators quickly linked the illnesses not to a pathogen, but to patients’ use of vaping products. By examining the chemicals in these products, they eventually found a chief suspect: vitamin E acetate. The compound was being used as a cutting agent in some counterfeit or illicit cannabis-based vaping products. Still, many questions remain about how vitamin E acetate could have caused those injuries and whether it was acting alone. In this episode of Stereo Chemistry, host Kerri Jansen and C&EN senior reporter Britt Erickson sift through the complicated chemistry of vaping and explore some new evidence in the investigation. They’ll also discuss how the tragic events of last summer could prove to be a wake-up call for chemical regulators as they evaluate vaping products.

The following is the script for the podcast. We have edited the interviews within for length and clarity.

Ruby Johnson: My daughter went from a healthy, vibrant 18-year-old to a patient who needed rapidly increasing amounts of oxygen and medications to treat her declining health. . . . I’ll never forget watching her cry that she literally couldn’t breathe without excruciating pain, as she was pumped full of IV fluids, antibiotics, steroids, pain meds, anti-nausea meds, and a diuretic to clear fluid from her badly inflamed lungs.

Kerri Jansen: The testimony we just heard comes from Ruby Johnson of Illinois, whose teenage daughter developed a terrifying lung illness that resulted in a weeklong hospital stay as she struggled to breathe. Although this story might bring to mind the symptoms of COVID-19, the disease caused by the novel coronavirus, the situation Ruby is describing happened months before the first cases of COVID-19 were reported.

Last summer, across the US, emergency rooms began reporting clusters of patients presenting with mysterious lung injuries, which caused breathing difficulty and, in the most severe cases, could lead to death. Scientists scrambled to identify a culprit, and eventually they hit on vaping products, electronic cigarettes that heat various liquids to vaporize their contents so that users can inhale ingredients like nicotine. The mysterious lung illnesses came to be known as EVALI, E-V-A-L-I, which stands for E-cigarette or Vaping Product Use-Associated Lung Injury.

By the time the US had reached the peak of the panic over EVALI, toward the end of September 2019, more than 800 people had become sick, and 12 had died. As the US Centers for Disease Control and Prevention and other organizations pursued a cause for EVALI, regular press briefings revealed the extent of what was unknown. Here’s Anne Schuchat during one of those briefings. She was part of a team investigating EVALI at the CDC.

Anne Schuchat: I know that this is very frustrating for the public and the media. It’s very frustrating for us. This is a complex investigation, and I don’t think that we should expect definitive answers imminently.

Kerri: In the months that followed, investigators did start to uncover some answers. A chemical called vitamin E acetate emerged as a prime suspect late last year after scientists reported finding it in the lung fluid of most EVALI patients that they tested, as well as in many products the patients had reported using. One additional piece of evidence supporting this chemical as the culprit is that ever since the possible connection between vitamin E acetate and EVALI was made public, emergency room visits related to the disease have declined, perhaps because the news spooked sellers who were using it in their products.

But the case is far from closed. Questions remain about how exactly vitamin E acetate could have caused those injuries, and whether it was acting alone.

In this episode of Stereo Chemistry, we’re going to sift through the complicated chemistry of vaping and explore some new evidence in the EVALI investigation. We’ll also look at how the tragic events of last summer could prove to be a wake-up call for chemical regulators.

I’m your host Kerri Jansen. And because I’m decidedly not an expert in chemical regulation, I’ve decided to call in someone who is. Joining me from her farm in West Virginia is Britt Erickson, a senior reporter at C&EN. Hi Britt.

Britt Erickson: Hi Kerri.

Kerri: Thanks so much for joining us for this episode. So you’ve been covering vaping chemicals for a while now. And I’m curious—when did you start to see vaping become a thing? It seems like at least in the last few years, there was some pretty significant growth in that area.

Britt: Definitely, I would say probably 2010 and beyond, but we didn’t see too much. I think I first covered it in 2016, when the federal government was starting to consider regulating e-cigarettes. We didn’t hear too much about the potential harm of e-cigarettes until the severe lung injuries that happened last summer. Then it really got attention, because young people were becoming ill.

Kerri: Now, there are tons of products on the market, and they’re divided into two main groups, nicotine-based products, which are often flavored, and cannabis-based products, which typically contain THC, tetrahydrocannabinol, the psychoactive ingredient in marijuana. The nicotine and THC is delivered in vape juice, or e-juice—that’s the liquid that gets vaporized by an e-cigarette. The devices themselves are usually handheld, battery-operated gadgets that heat vape juice to produce an inhalable vapor.

Britt, you were telling me that vaping products are generally marketed at people to help them stop smoking traditional combustible cigarettes. The idea is that because regular cigarettes are combustible, they generate cancer-causing compounds that e-cigarettes don’t. Unfortunately, you also mentioned that e-cigarettes have become popular with younger people?

Britt: What we have seen is a huge uptick in the number of youth taking up vaping, because some of the flavors are appealing to kids. Things like cookies and cream or watermelon. So a lot of teenagers are vaping. We’ve seen the statistics and they’re really high right now. I think it’s close to 25% of high school students have vaped within the last month.

Kerri: Right. We all saw headlines about the cartridge-based e-cigarettes—the Juul brand, for example—that particularly appealed to young people because they’re more easily concealed. When the EVALI outbreak started, I know the investigation was complicated by the fact that patients would have used multiple products. For instance, an e-cigarette like a Juul, maybe also a cannabis-based vaping product, and some people were smoking traditional cigarettes, too. All of that had to be evaluated, right?

Britt: Right. A lot of the patients were doing both nicotine and THC products. So there was confusion over what was causing the illnesses. We also don’t know a lot about what’s in these products. So that’s, you know, if you don’t know what it’s in them to begin with, it’s kind of hard to figure out what’s causing the problem.

Kerri: And in this episode we’ll hear from some of the scientists who are trying to answer that exact question: Exactly what is in these things. And what happens when the chemicals in these vape juices get into your lungs. The EVALI outbreak seems to have drawn a lot of attention to this issue.

Britt: Absolutely. I think people are more concerned about what is in the vaping products than they were before. I think what really came out was how much we don’t know about what is in these products, particularly the flavors. Some of the chemicals in vaping liquids might be perfectly safe when ingested, but we know very little about what they do to your lungs. They simply weren’t designed to be inhaled.

Kerri: We’re going to come back to our prime suspect in the EVALI case, vitamin E acetate, a little later in the episode. But even before the spike in lung injuries last year, scientists had been exploring vape juice and raising concerns about its health effects. Robert Strongin is one of them. He’s an organic chemist at Portland State University who started studying vape juice after seeing the products crop up all around campus and in Portland.

Robert Strongin: You know, it seemed all of a sudden one day they were everywhere. They seemed to pop up very, very quickly. We basically were very suspicious. These were being touted as safe, completely safe materials made up of water vapor. And there’s very little water in these.

Kerri: What Rob’s talking about here are e-cigarettes that deliver nicotine. The vape juices in these devices dissolve nicotine primarily in a pair of solvents: propylene glycol and vegetable glycerin, nicknamed PG/VG. Both chemicals are commonly used in personal care products and as food additives. The propylene glycol is a thin, runny liquid that helps prevent vape devices from gunking up, and it produces a throat sensation that some users prefer because it’s similar to the experience of smoking tobacco. The glycerin has a slightly sweet taste, and it helps create those big clouds of white vapor you see. And there are also some flavoring compounds in the mix.

What concerned Rob is that, although the solvents and the flavoring compounds were considered food safe, it was largely unknown how they behaved when heated, vaporized, and inhaled.

Robert Strongin: Our lungs and our lung tissue are very sensitive. And as things get delivered in the lungs, they go right to the bloodstream without any protective processing from our bodies.

Kerri: Rob hypothesized that the temperatures used by most vape devices to heat the e-juice—generally between 190 and 230 degrees Celsius—would accelerate the breakdown of the chemicals in vape juice, creating any number of unknown chemicals. So for the last several years, he and colleagues have been working to identify and understand the chemical reactions involved in vaping. To do this, he uses something called a smoking machine. I was picturing like a mechanical hand clutching a vape pen, but it turns out that’s not what it is. Rob describes his smoking machine as more like a vacuum, just a normal piece of nonhumanoid lab equipment you can buy. It’s fairly common in labs that study vaping. You can vaporize a sample and then collect the volatiles with this vacuum device for further study.

Britt: Yeah. So they have been using smoking machines for a very long time to look at what is in tobacco products. And they can set them so that it mimics the amount of puffing that a normal person would do. You’re trying to mimic what a person would do without using a person.

Kerri: Right. Using the smoking machine, Rob’s team studied how people themselves could affect what they’d inhale.

Robert Strongin: Everybody’s a little different, and one of the things we found is yes, it actually does affect the chemistry. The inhalation rate can actually affect the amount and type of degradation products that one can find.

Kerri: Taking that variability into account, Rob and his team began examining solvents like PG/VG. Solvents are the main components in noncannabis vape juices, making up the bulk of the liquid.

The scientists confirmed that propylene glycol and glycerin would decompose with heat to form toxic aldehydes like formaldehyde, acetaldehyde, and acrolein. They also explored other vape juice components like the flavor enhancer triacetin. They isotopically labeled the chemicals so they could track them as they broke down and interacted with other compounds in vape juice.

More recently, the team has turned to the flavor chemicals in e-cigarettes. There are thousands of flavoring formulations, but most pull from a set of a couple dozen popular chemicals, Rob says. These flavor compounds are typically organic, aromatic molecules like vanillin, which has, you guessed it, a vanilla flavor. Chocolate flavors often rely on pyrazine. The team is now isolating and identifying these compounds’ breakdown products and studying how they interact with the solvents. The work is ongoing, in part because the development of new vape juice flavors is also ongoing.

Robert Strongin: New formulations and new device types come out with regularity. There are new designs all the time. So it’s a very dynamic field; the target keeps moving.

Kerri: But identifying the chemicals present in the breakdown products of e-juice is just the first piece of the puzzle. Rob says that for most of these chemicals, we just don’t know what their effect is on lungs, and at what levels they may be unsafe.

Robert Strongin: One of the big problems in the field, every time we find a new breakdown product, is there’s very little toxicological data. I think that’s the main reason there’s so much unknown, is because no one ever thought people would be inhaling these chemicals! No one ever imagined. It’s been frustrating that we don’t have tox data on most of the ingredients in e-cigarettes. And there’s a big, big need for it, as these materials continue to be used. And, you know, it’s kind of the Wild West.

Kerri: So Britt, I wanted to come back to you a little bit here. Rob is invoking the lawlessness of the early American frontier to express what I think is his frustration at there not being more control of what’s going into these products. My understanding of the Wild West, which, full disclosure, is based solely on the HBO series Deadwood, is that it was kind of a free-for-all, there weren’t a lot of enforceable rules, everyone had to fend for themselves. So thinking about nicotine- and cannabis-based vaping products, is that an accurate comparison? I mean, who’s in charge here?

Britt: Right, it is kind of the Wild West. Let’s start with cannabis. Because cannabis is a Schedule 1 substance under the Controlled Substances Act, it’s illegal at the federal level. So the FDA really cannot regulate it. But it’s not illegal in some states. Each state has different laws governing cannabis and cannabis vaping products. Now with nicotine vaping products, the Food and Drug Administration has authority to regulate them, but they’ve sort of kicked the can down the road for many years, rather than exercise their authority. Recently, though, a lawsuit brought by public health and anti-tobacco groups resulted in a court order forcing the FDA to step in and regulate e-cigarettes. Now, under that order, the FDA must soon require manufacturers to submit applications to get approval for their products. As part of that approval process, it might be that the FDA will require manufacturers to list the ingredients in their products, but we don’t know whether that will happen for sure.

Kerri: So manufacturers are not required, on a federal level, to disclose all of their ingredients currently.

Britt: That’s correct. We really don’t know what’s in these flavors.

Kerri: How are flavoring chemicals typically regulated, independent of vaping products?

Britt: Well, a lot of them are regulated as food additives, and they are what’s called “generally recognized as safe.” But it’s one thing to be ingesting a chemical. It’s another thing to be inhaling a chemical. We really need to know how these chemicals affect your lung tissue. I mean, it’s nice to know what’s in there, but we need to know what effects they’re going to have on people.

Kerri: And so there are some scientists who are studying the health effects of vaping chemicals. I spoke with Irfan Rahman at the University of Rochester Medical Center, who, like Rob, was studying this subject long before the EVALI outbreak hit the news cycle.

Irfan Rahman: This is an important question, what dose, and what time, and how long of exposure can lead to toxicity. So we are working on that. And once we identify a chemical in those liquids and vapors, then we look at the effect of those chemicals, whether they’re toxic or not.

Kerri: Irfan’s team is screening thousands of chemicals for negative health effects, using human cells, mice models, and even interviews with humans who vape. What they found is that the chemicals in common vape juices can disturb delicate lung cell structures, damage DNA, and generally irritate lung cells. That can change the way lung processes work. And, worse, Irfan says that once the body recognizes that damage, it reacts with an inflammatory response, which can lead to injuries associated with pneumonia.

Irfan and his team were in the midst of studying the health impacts of e-cigarette use when he started hearing reports last summer of a new lung illness from the medical center’s affiliated hospitals.

Irfan Rahman: So that put us last year in June, some serious lung injurious responses they started seeing in our hospital. Doctors informed me that there are cases coming here and it looks like acute lung injury, like a pneumonia, and they didn’t have a clue what was happening.

Kerri: Patients were coming in with a variety of symptoms, but primarily cough, shortness of breath, or chest pain. Most were young, otherwise healthy people. Many deteriorated quickly and required mechanical ventilation. There was no treatment available except supportive care—helping the patient stay alive and breathing while waiting for their body to heal. Some patients did not recover.

Irfan calls this time “a nightmare.” Identifying a cause of these injuries was still months away. And in Texas, pulmonary physician Farrah Kheradmand was seeing the same thing.

Farrah Kheradmand: It sort of started in July, maybe late June, in clusters of patients who presented with shortness of breath, hypoxemia, meaning low oxygen saturation, and on chest X-ray or CT scan of the chest, they would have evidence for a pneumonic process.

Kerri: “A pneumonic process” meaning the scans would show inflammation of the lung’s air sacs, which interferes with the lungs being able to do their job. Farrah says typically, this type of damage to lungs arises because of an infection with a virus or bacterium. But those tests were coming back negative.

Farrah Kheradmand: The viral pathology, bacterial culturing, all of that would be negative in these young people that otherwise had no other health issues.

Kerri: That’s when doctors started to realize that the cause of these illnesses was something other than a pathogen, something they hadn’t seen before. As case numbers climbed, health officials and scientists embarked on an investigation that would lead them to eventually point the finger at vaping, and more specifically, vitamin E acetate.

We’ll continue with that story after a quick break. When we come back, we’ll look at the evidence that led investigators to vitamin E acetate and explore why some think the mystery isn’t yet solved.

Dorea Reeser: Hey everyone, Dorea Reeser here. I’m C&EN’s senior audience engagement editor. Here at C&EN, we’re working hard to keep you up to date on news related to the COVID-19 pandemic. And we know the flood of information can feel overwhelming. So C&EN has collected all of its coronavirus stories in one place, at cenm.ag/coronavirus. There, you’ll find the latest news on virus biology, vaccine development, and how the pandemic is affecting the chemistry community. You’ll also have access to free webinars, including a recent one about repurposing existing drugs to treat COVID-19, moderated by C&EN’s pharma editor, Lisa Jarvis.

Again, you can find all those stories and more at cenm.ag/coronavirus. That coverage is available for free, and if you’d like to support our nonprofit journalism with a donation, there’s now a way for you to do so. You can find more information at donate.acs.org, and we’ll post a link in this episode’s description.

Thank you for your support. We’re proud to bring you rigorously reported news about the race to understand and respond to COVID-19. And now, back to the show.

Kerri: We left our story just as doctors started to see a pattern in cases of a new lung disease with no obvious cause. By the end of June 2019, dozens of people had become sick, and health officials were determined to pinpoint a culprit. Britt, you were following this investigation in the early stages last year. Can you describe what you were seeing?

Britt: In the beginning, there really wasn’t a clue as to what was happening. They weren’t even sure whether it was a THC vaping product or a nicotine vaping product. People were really at a loss as to what the heck was going on. They knew that young people were dying, and they didn’t know why it was affecting young people. So it was really a mystery for quite a few weeks.

Kerri: At first, the investigation was focused on analyzing samples of vape juice provided by the patients, but the problem was that many of the samples were mostly empty, so there wasn’t a whole lot of liquid there for testing. And as people began looking at other vape juices, not necessarily used by EVALI patients, they started finding all sorts of things that aren’t good for you, like heavy metals, pesticides, other contaminants. So there were a lot of theories flying around in the first couple of months after case numbers really began to climb in June.

Britt: It really wasn’t until September, when the New York Department of Health discovered vitamin E acetate in several of the samples that they had analyzed. And it was sort of this aha moment that maybe it’s the vitamin E acetate.

Kerri: Vitamin E acetate is an ester, and it’s the product of vitamin E reacting with acetic acid. It’s got a long hydrocarbon chain on it, making it greasy, so it’s often used in products like hand creams. You’ll also see it in multivitamins. During the EVALI investigation, which was probing all sorts of vape juices, the chemical was primarily found in THC-based products.

Britt: And it wasn’t even legal THC products that were purchased at dispensaries. These were products that were bought off the street informally. They were given to people by their friends. They were purchased online over the internet. They were counterfeits. It wasn’t the legal products.

Kerri: Meaning that in some states, THC products are legal, and you can purchase them at stores called dispensaries. But there is still a black market in those regions as well as in places without legal options.

Britt: Right, in some states, it’s still completely illegal, whereas in others it’s OK to use recreationally.

Kerri: OK, so the vitamin E acetate was showing up in THC-based vape juice. But not the kind you’d get at dispensaries. It was showing up in vape juice acquired from what officials have been calling “informal sources”—counterfeit or illicit products. The black-market sellers would use vitamin E acetate as a cutting agent, meaning that they could dilute vape juice without changing its viscosity in a noticeable way. Essentially, they were pulling a fast one to make more money on a diluted product.

Britt: So you’re not getting what you think you’re getting. There’s no requirements for labeling. Whereas in a dispensary, they have to tell you how much THC is in the product. If you’re buying it from the black market, you have no idea what you’re getting. It could be laced with pesticides, heavy metals. In the black market is probably a lot of the products that were rejected from the legal market.

Kerri: According to trade websites and law-enforcement reports, vitamin E acetate was a fairly recent addition to vape juice, appearing on the market as recently as late 2018. And CDC scientists reported finding vitamin E acetate in most of the samples they tested of lung fluid from EVALI patients. It was absent from samples from healthy people. That’s certainly a compelling link. But remember, vitamin E acetate was already common in multivitamins and cosmetics—we eat this stuff and smear it on our skin without a problem. Scientists didn’t know how that chemical could cause the severe, life-threatening symptoms seen with EVALI.

So they got to work to find a mechanism that would confirm that vitamin E acetate was responsible for EVALI, or find an alternative cause, keeping in mind that their explanation would have to account for two prevailing markers of the EVALI cases. The first is lipoid pneumonia, a specific form of pneumonia where lipids—fat molecules—accumulate within immune cells in the lungs, disrupting the lungs’ function and starving the body of oxygen. It might make sense that vitamin E acetate could cause this condition because it has that greasy hydrocarbon chain, so some scientists thought it could be simply accumulating in lung tissue.

But a second marker of EVALI was more puzzling. Samples of lung tissue from the worst cases revealed more severe damage—areas of lung tissue that had been completely destroyed. You may have heard this characterized in news reports as resembling chemical burns. Such injuries didn’t seem to fit the theory that inhaled fats were to blame.

Donal O’Shea: You couldn’t see this type of chemical damage, chemical burn-type damage from vitamin E acetate alone. So, yeah, a complicated story becoming even more complicated.

Kerri: That’s Donal O’Shea, a chemist at the Royal College of Surgeons in Ireland. Donal says that although Ireland didn’t experience a vaping-related outbreak like the US did, the overseas news reports pinpointing vitamin E acetate as a key suspect piqued his interest. He was familiar with a related compound, phenol acetate, and knew that when heated, the chemical produces a potent toxin, ketene gas. Ketenes are compounds with a carbon-carbon-oxygen group, where there are double bonds between all three of those atoms. Perhaps the same poison was lurking in the byproducts of vitamin E acetate.

Donal O’Shea: From a pure chemistry point of view, I guess what I knew was that a simple phenol acetate produces ketene upon pyrolysis. I didn’t know for certain if the vitamin E acetate would produce it, but suspected that it would.

Kerri: Donal used a commercial e-cigarette device to vaporize vitamin E acetate. He collected the vapors, and ketene was there. Donal published the results in the journal PNAS in March.

Although it’s a compelling lead, Donal’s research doesn’t confirm that vitamin E acetate–derived ketene caused the EVALI outbreak. That would require further studies. But it’s one possible explanation for those so-called chemical burns.

And then there’s something else that’s still unexplained in this investigation. Vitamin E acetate was found in most samples that were tested from EVALI patients, but not all of them. Now, it’s possible that some patients’ illnesses were misattributed to EVALI. But the CDC’s official position is that it hasn’t yet ruled out the possibility that an alternative cause for EVALI may exist—or that there were multiple causes.

rfan, the biochemist in Rochester, is one of the scientists who thinks multiple factors could be responsible for the EVALI outbreak. His team has been analyzing vape juice cartridges from EVALI patients to look for other ingredients that could be involved. In a recent paper in the journal Toxics, the researchers list several chemicals found in those samples that are known to cause symptoms that match EVALI. The lineup includes decane, naphthalene, isoprene, and silicon dioxide.

Irfan Rahman: Each individual chemical can have the EVALI-like symptoms when inhaled. So these are the top three, four chemicals which we identified as a suspect, chemicals that can cause pneumonia.

Kerri: And it’s also possible that various factors could overlap and compound to cause EVALI. The problem with taking this research any further is that many of the labs studying this problem—particularly those studying lung effects in animals—are at a standstill because of the COVID-19 pandemic.

One bit of good news is that cases of EVALI are on the decline. The illness hasn’t disappeared entirely, but the CDC reports a consistent downswing since the outbreak peaked in September. By February, when the CDC ceased reporting updated numbers, the weekly tally of cases had dropped into single digits. And the increased attention EVALI has forced on vaping products could ultimately result in a safer market. We’re already starting to see glimmers of change.

And that brings me back to you, Britt. I wanted to talk with you more about what it could look like to regulate these chemicals in the future. Did you see the dialogue around regulation change after the EVALI outbreak?

Britt: It absolutely did. There were a lot of calls early on to legalize cannabis at the federal level, but it’s unclear whether that would actually solve the problem. In states where cannabis is legal we still have a huge black market.

So on the nicotine side, what ended up happening is the FDA banned flavors in only these e-cigarettes with the enclosed cartridges, like the Juuls. So that’s just a small segment of the industry; it didn’t really stop the youth from vaping. There have been flavor bans at the state level. And I think we’re gonna start seeing more and more state-level actions if the FDA continues to drag its feet.

Kerri: And you mentioned earlier that the FDA is now moving toward regulating this market a little bit more. What do you think the impact of that will be?

Britt: The FDA is now requiring manufacturers to submit applications to show that their products are appropriate for the protection of public health. Now, what that means is a little unclear. But they will have to show the likelihood that kids will take up these products vs. the likelihood that people will stop smoking because of them. It’s this balancing act that they have to do. The deadline for those applications was originally May 12, but the FDA requested an extension because of the pandemic, and the new deadline is in September. But it could be the first that we see companies actually trying to figure out how they’re going to show that their products are appropriate for public health.

As far as how that will impact the market? Especially for the small mom-and-pop-type businesses, the cost of meeting those regulations can really be a burden. The big companies have the money to do the testing, the little companies don’t. And I think we will see regulation at some point. I don’t think it’s gonna be an if but a when. And I think the big guys are gonna win out here because they have the money to do all the testing.

Kerri: Pro-vaping organizations like the American Vaping Association and Vapor Technology Association have focused on the protection of small businesses as one of the key reasons they’re pushing for so-called “smart” regulations, or “fair and sensible” regulations. Neither organization responded to my questions about what that means. Their supporters maintain that e-cigarettes and other nicotine-containing vapor products are designed to provide adult smokers an alternative to cancer-causing cigarettes, and they’ve criticized statements that seem to conflate nicotine products with the THC-containing products linked to the EVALI cases.

Britt: Right. I think the feelings toward regulation might be a little different for the cannabis industry. The role of illicit THC products in the EVALI outbreak really threatened to cast the entire industry in a bad light, and so having more transparent quality control could help ensure trust in the legal market. We’re gonna continue to see states take the lead. I don’t think federal legalization of cannabis is on the horizon in the next few years. So I think it’s up to the states to do what they can to create a safe product.

Kerri: Well, thank you for sharing your expertise with us in this episode, Britt. Keep an eye on C&EN as we continue to cover the EVALI investigation. And I’m happy to say that Britt will be returning to Stereo Chemistry next month for a look at the Toxic Substances Control Act, TSCA. Britt, can you tell us a little about that story?

Britt: Yeah. So TSCA is the law governing the management of chemicals in the US. And about 4 years ago that law was revised, and so we’re going to look at how the Environmental Protection Agency has been implementing those changes, which involves evaluating new chemicals before they hit the market and assessing the risks of certain chemicals that have been in use for decades. Is the EPA protecting public health, or is it giving the chemical industry a free pass? That’s what we’ll explore.

Kerri: Be sure to subscribe to Stereo Chemistry so you don’t miss it.

This episode of Stereo Chemistry was written and produced by me, Kerri Jansen. It was edited by Lauren Wolf, Jyllian Kemsley, and Bibiana Campos Seijo. Heather Holt was our copy editor. The music in this episode was “Bring to Light” by Max H., “Plain Loafer” by Kevin MacLeod, and “Intimate” by Slpstrm. Stereo Chemistry is the official podcast of Chemical & Engineering News, which is published by the American Chemical Society.

Kerri Jansen/C&EN