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Cited by 137Smoking Behavior and CessationForensic Toxicology and Drug AnalysisIndoor Air Quality and Microbial Exposure

Potential for Release of Pulmonary Toxic Ketene from Vaping Pyrolysis of Vitamin E Acetate

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Wu, Dan, O’Shea, Donal F.·2020·Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.1920925117PMC PMC7104367

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Abstract

Significance: The Centers for Disease Control and Prevention has recently reported an increasing number of clinically cases of lung injury following use of vaping products. The cause(s) of this growing epidemic of vaping-associated pulmonary injury remain unidentified, although vitamin E acetate has been identified as one possible causative agent. In this research, a combined analytical, theoretical, and experimental study has shown that the vaping of vitamin E acetate has the potential to produce exceptionally toxic ketene gas, which may be a contributing factor to the upsurge in lung injuries associated with vaping products. Our important results will help inform medical practitioners, research scientists, and the public, which may assist in bringing this medical crisis under control.

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  • Not all vapes contain Vitamin E acetate (VEA), but VEA has been commonly found in illicit THC vape products and is strongly linked to EVALI due to its toxic effects when inhaled.

    “Despite the fact that not all vapes contain Vitamin E acetate (VEA), it has been commonly found in illicit THC vape products and is strongly linked to EVALI due to its toxic effects when inhaled [18,19,20].”

    From Mobilizing for Health: A Case Study of Kazakhstan’s Vaping Ban Advocacy Campaign (2025) · cites this paper as [19]

    The Abstract (page unavailable) says VEA is added to some vape mixtures, especially those containing THC, and reports its detection in lung-fluid samples from 48 of 51 patients with vaping-associated injury. It does not establish that VEA is commonly found specifically in illicit THC products. The Abstract identifies VEA only as a possible cause, while the Experimental Analysis (page unavailable) says the direct relevance of its toxic pyrolysis products to lung injury remains uncertain; the claim's causal wording is therefore too strong. (LLM, conf=0.87)

    Experimental — accuracy not yet measured

  • In the first six months of 2022, vape sales in Astana and Almaty increased by 372%.

    “In the first six months of 2022 alone, vape sales in the country’s two largest cities—Astana and Almaty—increased by 372% [19,28].”

    From Mobilizing for Health: A Case Study of Kazakhstan’s Vaping Ban Advocacy Campaign (2025) · cites this paper as [19]

    The Abstract discusses lung injury and ketene released by vaping vitamin E acetate; the Experimental Analysis discusses vaping pyrolysis. Searches for Astana, Almaty, Kazakhstan, 2022, and a 372% sales increase found no passage addressing the cited sales claim. (LLM, conf=0.78)

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Cites

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Research works printed but not linked: 19

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Sorted by citations

Authors
Wu, D., & O’Shea, D. F.
Affiliations
Royal College of Surgeons in Ireland (IE)
Corresponding author
  • Wu, Dan
  • O’Shea, Donal F.
ORCID
Venue
Proceedings of the National Academy of Sciences
Publisher
National Academy of Sciences
Published
2020-03-10
Volume
117
Issue
12
Pages
6349-6355
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
DOI
10.1073/pnas.1920925117
PMC
PMC7104367
OpenAlex
W3010753680
Cited by
137
References
0
Citations by year
2026: 7 · 2025: 15 · 2024: 12 · 2023: 14 · 2022: 28 · 2021: 26 · 2020: 34 · 2019: 1
FWCI
15.48
Type
journal article
Language
en
Open access
Licence
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion, cc-by-nc-nd)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by-nc-nd)
  • PubMed Central (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
  • Lenus, The Irish Health Repository (Dr Steevens Hospital Library) (submittedVersion)
Funders
  • Science Foundation Ireland (RC/2275)
  • SSPC Research Centre (RC/2275)
Topics
  • Health Sciences › Medicine › Physiology › Smoking Behavior and Cessation
  • Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Toxicology › Forensic Toxicology and Drug Analysis
  • Physical Sciences › Environmental Science › Health, Toxicology and Mutagenesis › Indoor Air Quality and Microbial Exposure
Keywords
alpha-tocopherol acetate, ketenes, vaping, electronic cigarettes, pulmonary toxicity, pyrolysis, lung injury, alkenes, benzene, public health education
MeSH terms
Vaping, Pyrolysis, Acetates, Ethylenes, Ketones, Phenols, Vitamin E, Molecular Structure, Lung Injury, Electronic Nicotine Delivery Systems

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