Myth: Vaping causes Popcorn Lung

Is Popcorn Lung the same thing as EVALI?

The two diseases are often conflated but are not the same.

While a variety of things can cause bronchiolitis obliterans (Popcorn Lung), it has been determined that E-cigarette, or Vaping, product use-Associated Lung Injury (EVALI) can be attributed to the addition of Vitamin E to make unregulated vape cartridges containing tetrahydrocannabinol (THC) from marijuana look thick and of higher quality. The additive was used for a brief period of time in 2019-2020. These thickeners were pulled from the market by their manufacturers as news of the EVALI outbreak spread.

Nicotine vapor products did not cause EVALI. Leading experts requested the Centers for Disease Control and Prevention (CDC) change the name of EVALI to help consumers better understand the difference between vaping THC and nicotine. The CDC declined to make that change.

Why are some experts claiming vaping causes Popcorn Lung?

In 2015 the paper "Flavoring Chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a Sample of 51 Products, Including Fruit-, Candy-, and Cocktail-Flavored E-Cigarettes" was published. The authors found Diacetyl in some of the e-liquids they tested. They concluded, "Our findings confirm the presence of diacetyl and other flavoring chemicals in flavored e-cigarettes. Because of the associations between diacetyl and bronchiolitis obliterans and other severe respiratory diseases among workers inhaling heated vapors containing diacetyl, urgent action is recommended to further evaluate the extent of this new exposure to diacetyl and related flavoring compounds in e-cigarettes." {The vapors that workers inhaled were not vapor from an e-cigarette.)

Harvard T.H. Chan School of Public Health issued a press release about the study, "Chemicals linked with severe respiratory disease found in common e-cigarette flavors (Link saved on Wayback Machine). While the safety of e-cigarettes does need to be monitored, the study and the press release did not compare the levels of the chemicals found to what is inhaled from smoking a combustible cigarette. Neither the paper nor the press release said people will get Popcorn Lung from vaping. They just raised concern about the possibility.

Carrie Arnold commented on this study and said, "this study did not assess levels of diacetyl, 2,3-pentanedione, and acetoin in actual users, much less health effects. So it’s premature to assume that exposure to these chemicals via e-cigarettes causes health problems."

The study and alarm over the potential danger of vaping made headlines across the US and globally. Most of the articles failed to mention there are more of these chemicals in combustible cigarettes, and there are no documented cases of Popcorn Lung being caused by smoking or vaping.

A chemical of concern that might pose potential harm swiftly morphed into known harm, and word began to spread that vaping causes Popcorn Lung, even though there were no documented cases of it actually occurring. A 2015 report published in the Milwaukee Journal Sentinal gave a historical run-down of cases of Popcorn Lung in the food industry and questioned why Diacetyl was allowed in e-cigarettes. The American Lung Association added information about Popcorn Lung and vaping on their website in 2016.

In 2018, Jonathan Winickoff, the former chair of the American Academy of Pediatrics Tobacco Consortium, a pediatrician at Massachusetts General Hospital and a professor at Harvard Medical School, said that he "believes that the vape industry is co-opting the national wellness trend—when, in fact, vaping can cause something called bronchiolitis obliterans, or popcorn lung."

Schools, in an attempt to keep teens safe and discourage them from experimenting with vaping began telling students they could get Popcorn Lung from vaping.

Misperceptions about the risk of getting Popcorn Lung from vaping can lead some people who smoke to avoid trying this safer alternative to help them quit smoking. A point that was made by Jennifer Pierce, Anders Abelmann, and Brent Finley in their commentary about the 2015 flavoring study.

What actions were taken to protect consumers after the study was released?

• Many e-liquid manufacturers switched to Diacetyl-free ingredients.
• Most flavor manufacturers reformulated their flavoring to Diacetyl-free formulas.
• As a further precaution to avoid the potential for their to be an issue in the future, some countries have banned the use of Daicetyl in e-liquids. Examples include Australia,Northern Ireland, Great Britain, and member states of the EU Tobacco Products Directive (TPD).

Are there any articles or Op-Eds trying to dispel this myth?

• October 17, 2019 - The Washington Post - Five myths about vaping
• September 12, 2023 - The Counterfactual - Is tobacco control the new Big Tobacco?

Who has corrected or deleted their incorrect information on Popcorn Lung?

• In December 2023, Harvard Health tweeted about Popcorn Lung. After a Community Note was post to it, Harvard deleted the tweet.

Who is sharing incorrect information on Popcorn Lung?

• American Lung Association
  • July 2016
  • January 2024.(wording slightly changed)
• World Bank Group Global Tobacco Control Program 2019
• World Health Organization
  • 2015 A systematic review of health effects of electronic cigarettes
  • 2021 WHO REPORT ON THE GLOBAL TOBACCO EPIDEMIC