VAPING

Vaping II

Stephan C. Jahn, Ph.D.

Pharmacology and Therapeutics

University of Florida

Primary Source: Cao et al, J. Med. Toxicol. (2020)

Health Risks of Vaping

 Definitive studies require long time-periods

 Early results show evidence of damage to  Cardiovascular system

 Myocardial infarction

 Stroke

 Respiratory system  COPD

 Increased infection risk

Myocardial Infarction

Alzahrani et al. Association Between Electronic Cigarette Use and Myocardial Infarction [published correction appears in Am J Prev Med. 2019 Oct;57(4):579-584]. Am J Prev Med. 2018;55(4):455‐461. doi:10.1016/j.amepre.2018.05.004

Vaping and COVID-19

 COVID-19 cases more common in vapers and smokers  Very early data

 Self-reported

Shivani Mathur Gaiha, Jing Cheng, Bonnie Halpern-Felsher, Association Between Youth Smoking, Electronic Cigarette Use, and Coronavirus Disease 2019, Journal of Adolescent Health, August 2020

E-Cigarette, or Vaping, Product Use- Associated Lung Injury  EVALI

 Popcorn lung

 Gained widespread recognition summer 2019

 Criteria  Vaping within 90 days  Widespread abnormalities in imaging

 Ground glass on CT

 No pulmonary infection

 Symptoms  Respiratory

 Acute inflammatory response

 GI

Ground Glass

Mukhopadhyay et al. Lung Biopsy Findings in Severe Pulmonary Illness Associated With E-Cigarette Use (Vaping). Am J Clin Pathol. 2020;153(1):30‐39.

Time to Sleuth

 Most patients reported >1 year e-cigarette use

 Prevalence seemed to be increasing

 Assumed to be a “non-active” ingredient

 Diacetyl is used as butter flavor  Origin of “popcorn lung”  Didn’t seem to correlate

 82% had used THC e-liquid  Likely underreported  Most common brand: “Dank Vapes”

 Nearly all THC e-liquid contains vitamin-E acetate

Vitamin-E Acetate

 VEA

 Used as diluent  Propylene glycol and glycerin reduce viscosity of oil

 Visibly apparent

 Can be up to 90% of e-liquid

 Most common in “homemade” e-liquid  Dank Vapes

 Cartridges filled by retailers

VEA

 Generally regarded as safe  In cosmetics/supplements

 Antioxidant  Better shelf-life than vitamin-E

 Converted to vitamin-E in intestines  Not in lungs

Toxicological Mechanisms of VEA

 1. Converts lung surfactant from gel to liquid-crystal  Loss of function

 2. Heated VEA creates reactive molecules  Damaging lung tissues

 3. VEA may accumulate in lungs regardless of administration route

 4. THC may react with VEA  Importance?

VEA Doesn’t Have All the Answers

 Not all cases show VEA consumption  Underreporting?

 Link to GI symptoms?

The Difficult Choice

1 2

Tout Risks Tout Safety vs. Smoking

Vaping I

Stephan C. Jahn, Ph.D.

Pharmacology and Therapeutics

University of Florida

Primary Source: Cao et al, J. Med. Toxicol. (2020)

Vaping

 Well-intentioned catastrophe  Safer

 Cessation

 Entered US market in 2006

 Vaping  Inhalation of aerosols

 Three primary purposes  Nicotine

 THC

 Flavor

Who Vapes?

 Nonpoor, young whites  Especially men

 Exponential growth  2018: 13.5% 8th graders, 34% 12th graders  2019: 40.5% of 12th graders  Most users 18-24

 Mixed reasons  Young

 Social  Flavors

 Older  Cessation

Vaping Devices  First generation

 One-time-use “cig-a-likes”

 Second generation  Reusable  Larger battery

 Third generation  “Mods”  Customizable

 Fourth generation  “Pods”  Flashdrive appearance  Juul  Marketed heavily to youth

Malanga and Smith https://www.sjuhawknews.com/health- officials-urge-students-to-stop-using- electronic-cigarettes/

E-Liquids

 Hard to pin down  Little regulation

 Rapidly changing market

 User refillable

 Inhaled components depend on heat generated by device  Potential for reactions or decomposition

Nicotine E-Liquids

 Contains:  Nicotine

 Purified

 Highly variable concentrations

 Juul has patent for nicotine acid salt to increase absorption

 Propylene glycol and/or glycerin  Thickeners

 Water

 Flavoring

 Concentrated nicotine poses threat to toddlers

Toxicology of Thickeners

 Propylene Glycol and Glycerin

 Extremely common in food, cosmetics, and pharmaceuticals

 FDA “generally recognized as safe”

 Inhalation is a whole ‘nother ball game  Alveoli very delicate

 Decomposition products  i.e. acrolein

 Two studies show vaping thickeners alone causes epithelial injury and decreased oxygen absorption

Other E-Liquids

 THC  Similar to nicotine e-liquids in constituency

 Even more variability due to illicit nature

 More likely to contain vitamin-E acetate

 Used by ~20% of cannabis users

 Alcohol/caffeine  Dosages are small compared to normal consumption

 Still dangers due to excipients

 Other illicit drugs

 Flavors only

Vaping Pharmacokinetics

 Best studied with nicotine

 One session administers an average of 4 mg  3-4x one cigarette

 Plasma concentration plateaus around 13 ng/mL  Roughly equal to one cigarette

 Slower climb

 Less addictive?

St Helen G, Ross KC, Dempsey DA, Havel CM, Jacob P 3rd, Benowitz NL. Nicotine Delivery and Vaping Behavior During ad Libitum E-cigarette Access. Tob Regul Sci. 2016;2(4):363‐376. doi:10.18001/TRS.2.4.8