Compiling Evidence for EVALI: A Scoping Review of In Vivo Pulmonary Effects After Inhaling Vitamin E or Vitamin E Acetate. J Med Toxicol 2021 Jul;17(3):278-288
Date
02/03/2021Pubmed ID
33528766Pubmed Central ID
PMC8206445DOI
10.1007/s13181-021-00823-wScopus ID
2-s2.0-85100353209 (requires institutional sign-in at Scopus site) 7 CitationsAbstract
BACKGROUND: Vitamin E acetate (VEA) has come under significant scrutiny due to its association with E-cigarette or vaping product use-associated lung injury (EVALI). Various theoretical mechanisms have been proposed for toxicity, including tocopherol (vitamin E)-mediated surfactant damage, recruitment of inflammation, and pyrolysis of acetate to the pulmonary irritant ketene.
OBJECTIVE: Characterize studies in mammals evaluating inhaled VEA, vitamin E analogues, or pyrolyzed acetate that describe subsequent effects on the lung.
ELIGIBILITY: Research in all languages from time of inception to October 1, 2020, regarding mammals (human or animal) exposed to inhaled vitamin E analogues, or any compound containing acetate administered via inhalation after pyrolysis, and subsequent description of pulmonary effect.
SOURCES OF EVIDENCE: Ovid MEDLINE, Scopus, and Web of Science Core Collection.
RESULTS: In total, 786 unique articles were identified. After duplicate reviewer screening, 16 articles were eligible for inclusion. Tocopherol was evaluated in 68.8% (11/16) of the studies, VEA in 18.8% (3/16), and both VEA and tocopherol were evaluated in 12.5% (2/16). Of the five studies evaluating VEA, it was given by pyrolysis in 60.0% (3/5). No human studies were identified. All included trials were conducted on non-human mammals: 75.0% (12/16) rodent models and 25.0% (4/16) sheep models. Outcomes assessed were heterogeneous and included 57 unique outcomes.
CONCLUSIONS: Several questions still exist regarding the pulmonary toxicity of inhaled tocopherol and VEA. More studies are needed to determine whether tocopherol alone (i.e., without acetate) can cause pulmonary injury. Additionally, further studies of VEA should evaluate the impact that pyrolysis and co-administration with other compounds, such as tetrahydrocannabinol, have on the toxic potential of VEA.
Author List
Feldman R, Stanton M, Suelzer EMAuthors
Ryan J. Feldman PharmD Adjunct Assistant Professor in the School of Pharmacy Administration department at Medical College of WisconsinMatthew Stanton PharmD Adjunct Associate Professor in the School of Pharmacy Administration department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
AcetatesAdult
Aged
Aged, 80 and over
Animals
Electronic Nicotine Delivery Systems
Female
Humans
Inhalation Exposure
Lung Injury
Male
Middle Aged
Models, Animal
Vaping
Vitamin E