Dry Puff: How Researchers Overturned The Formaldehyde E-Cig Scare

Many e-cig users were disturbed by the findings of researchers at Portland State University who discovered that, just like traditional cigarettes, vaporizers could produce formaldehyde, a highly toxic chemical that causes cancer.

Do Vapes Actually Create Formaldehyde?

Studies like this have been linked to sharp drops in the public perception of e-cigarettes. In 2010, around 84% of current smokers believed that vaping was safer than traditional cigarettes. By 2013, that proportion had declined to 65%. But scientific results are never as simple as “good” or “bad,” and the media has a tendency of dumbing down findings to spin out eye-catching headlines.

True to form, the “formaldehyde study” is far more complicated than the sensational logic behind headlines like “Before You Vape: High Levels Of Formaldehyde Hidden In E-Cigs” (a story NBC News ran in January 2015).

Misleading E-Cig Study Warrants Closer Look

For one thing, the study looked only at personal vaporizers, complex devices that allow users to control the voltage with which eLiquid is made into vapor. That distinction turns out to be crucial, since you can’t change the voltage on convenience store e-cigs and (most) vape pens, and it’s really the voltage at which you vape that creates formaldehyde.

In theory, e-cigarettes do produce formaldehyde. At least one of the primary constituents of eLiquids, propylene glycol, is known to degrade into formaldehyde. So it’s not a stretch to suspect that vapes could create the dangerous chemical. But in their own study, the researchers from Portland State found that at low voltage, 3.3 volts, vaporizers didn’t actually create any formaldehyde. In reality, the carcinogen was only produced at an extremely high voltage, 5.5 volts. Admittedly, high voltage produced a lot of formaldehyde. The readings were so high that the researchers estimated an average vaper would be exposed to around 14 milligrams of formaldehyde every day.

Of course, traditional cigarettes produce formaldehyde, too. Depending on your study of preference, a pack of 20 combustible smokes exposes smokers to between 1 and 4 milligrams of formaldehyde. Obviously, that number is a lot lower than the 14 mg observed for vapes at high voltage, enough for the study to conclude that vaping could increase the risk of developing cancer 5 times over and above the risk with traditional cigarettes.

From Lab To Reality

There was, however, a slight problem. In the real world, vapers don’t use extremely high voltages. As anti-smoking organizations and pro-vape groups would soon point out, vaping at around 5 volts creates what e-cig users call the “dry puff phenomenon,” a taste too acrid for any palate to withstand. It’s a result, very literally, of overheating the vaporizer. At both voltages, the researchers had set their artificial puffing machine to take ten three-to-four second long puffs over the course of five minutes – something no vaper would actually do. In the real world, e-cig users shorten each puff as voltage increases, thereby avoiding “dry puffs” and, apparently, the production of formaldehyde.

But media sources, and anti-vaping lobbyist groups, grabbed onto the story and wouldn’t let go. Part of the problem is that the New England Journal of Medicine, one of the most respected medical journals in the world, published the Portland State paper. At least in the eyes of journalists, the research had been granted an instant patina of “quality science,” despite having nothing to do with the realities of vaping. Addiction experts, on the other hand, weren’t convinced.

Calls To Retract Paper Go Unheeded

In October 2015, the journal Addiction published an editorial the point of which should be apparent from its title: “Research letter on e-cigarette cancer risk was so misleading it should be retracted.” As anti-smoking campaigner Clive Bates and cardiologist Konstantinos Farsalinos put it the Portland State paper’s “calculations of human cancer risks [were] based on conditions that no human user would tolerate even momentarily, let alone over a full life-time.”

A flurry of critical responses followed, with Bates, Konstantinos and the paper’s original authors trading blows in a number of scholarly journals. While the debate soon became acrimonious, the New England Journal of Medicine refused to retract the paper. It still hasn’t, for a very simple reason: the study’s results weren’t actually fraudulent. Under the study’s conditions, well-documented in the paper, vaporizers did in fact create formaldehyde. The science was sound.

Bates and Farsalinos, though, argue that science doesn’t live in a vacuum. It will be interpreted by the public, so researchers have a duty to present their findings in ways that are hard to misinterpret. Beyond that, scientists have a duty to tackle the e-cig question under realistic conditions, not in artificial laboratory settings that share little resemblance to how vapers actually vape.

Bringing E-Cig Research Into The Real World

Thankfully, another team of scientists decided to take the formaldehyde scare head-on. In March of 2016, the journal Regulatory Toxicology and Pharmacology (a peer-reviewed journal dedicated specifically to helping government agencies put scientific data into practice) published a paper called “Effect of variable power levels on the yield of total aerosol mass and formation of aldehydes in e-cigarette aerosols.”

Testing 5 variable-voltage vaporizers, researchers at Penn State found that, despite drastic differences in the amount of formaldehyde produced, 3 out of the 5 e-cigs produced formaldehyde levels far lower than those found in traditional cigarettes, even at the highest voltage possible.

One device produced more formaldehyde than cigarettes, but only at its max voltage. Another e-cig, though, created more formaldehyde than combustible smokes at its lowest voltage. Set to its maximum voltage level, that e-cig, specified only as a “single top coil” vaporizer, produced more than 10 times the formaldehyde allowed by the Occupational Safety and Health Administration.

Even so, the researchers were careful to hedge their findings: “the results for Device 1 [which produced the high levels of formaldehyde] may not represent typical usage of this device, we hypothesize, and a typical user might experience noxious dry-puff effects and discontinue use at that power setting.”

Simulating Actual Vapers

Similar results were confirmed in an analysis presented at the Society for Research on Nicotine and Tobacco’s annual conference in Chicago. While the study was conducted by British American Tobacco, a large cigarette manufacturer, it really doesn’t seem horribly biased. It also took real-world variations in vaporizer use into account.

Close Up Of E-Cig During Use

The researchers used “lab-based vaping robots,” but programmed the machines to replicate e-cig use “in a realistic way.” Testing three different types of vaporizers (a “cig-a-like” vaporizer, a vape pen with clearomiser and a mod with variable voltage), the study found that none of the vapes produced a significant amount of formaldehyde. Wherever possible, the e-cigs were pushed into overdrive, replicating “worst case scenarios” at the highest possible voltage. Even under extreme conditions, the vaporizers produced well below the amount of formaldehyde acceptable to the World Health Organization.

Dr. Farsalinos even threw in his two cents, using “experienced vapers” to estimate the amount of formaldehyde produced by vaporizers under real-world conditions. In his study, published in Addiction‘s August 2015 edition, Farsalinos concluded that “electronic cigarettes produce high levels of aldehyde only in dry puff conditions, in which the liquid overheats, causing a strong unpleasant taste that e-cigarette users detect and avoid. Under normal vaping conditions aldehyde emissions are minimal, even in new-generation high-power e-cigarettes.”

Smart Regulations Require Quality Science

In most cases, then, it seems unrealistic to believe that vapers are at risk of inhaling dangerous amounts of formaldehyde. Does that mean e-cig manufacturers don’t have to worry about warning their consumers to the possibility? Not at all. Propylene glycol can turn into formaldehyde. Vapers have a right to know about that, and make their own informed decisions. But in the run-up to the US Food & Drug Administration’s announcement that e-cigs will be strictly regulated, politicians were still citing Portland State’s study as evidence of vaping’s dangers, without providing the necessary caveats.

What’s the upshot? Instead of demonizing vaporizing off-the-bat, we should be regulating the voltage at which e-cigarettes work and educating vapers on safer ways to use their devices. As currently sold, e-cigarettes vary widely in their characteristics, function and safety; that’s the lesson to be learned from the study conducted at Penn State. As we saw, one of the vaporizers produced more formaldehyde than e-cig users are likely to accept of their own accord. Caution, and thoughtful regulation, are obviously necessary.

The vaporizing debate has been fraught with misinformation – and fear – from the beginning. While we should be extremely careful in approaching this new technology, using out-dated studies to score political points is just bad science. It also takes our attention away from legitimate dangers, like the rash of recent e-cigarette explosions that have captured so much media attention. In all likelihood, cheap and defective e-cig batteries are being sold directly to consumers across the country. That’s something we should all be worried about.

Formaldehyde Risks Are Low. But What About Other Chemicals?

Vaping liquids may not be out of the woods yet, though. Recent research from Harvard’s T.H. Chan School of Public Health found three pretty dangerous chemicals hiding in flavored eLiquids.

Testing 51 flavored vapes (specifically flavors that seemed “appealing to youth”), a group led by Joseph G. Allen discovered that a vast majority of the e-cigs contained at least one flavoring chemical that researchers believe may cause severe respiratory diseases. Detected in 46 out of the 51 flavors, 2,3-Pentanedione was most common, followed closely by diacetyl. A similar chemical, acetoin, was found in 23 of the 51 vapes.

In the paper, Allen et al note that diacetyl was first linked to a condition dubbed “popcorn lung” in the early 2000s, after workers at a microwave popcorn plant in Missouri began coming down with bronchiolitis obliterans. Diacetyl is often used to flavor the artificial butter used in popcorn, which is really scary since, just as with vaporizing, most people prefer their popcorn hot. Worse, bronchiolotis obliterans, which happens after the airways in your lungs fill up with scar tissue, can only be treated through a lung transplant.

But again, this new data out of Harvard hasn’t been independently confirmed. As we learned from the vaping formaldehyde controversy, our conclusions should never be based on a single study, no matter how fool-proof the methodology. Science isn’t so much about proving facts; it’s about disproving myths. As one final example, the Harvard study never even mentioned that traditional cigarettes expose smokers to around 750 times the amount of diacetyl found in flavored vapes.