The impact of e-cigarettes on the brain could be similar to that of traditional cigarettes

Several studies indicate that the brain effects of nicotine exposure are also present with e-cigarettes, particularly in adolescents and due to higher nicotine concentrations.

The success of e-cigarettes has sparked a lot of research to assess their toxicity. While data is accumulating on the impact of vaping on the respiratory and cardiovascular systems, several studies show that it also has consequences on brain function, particularly in adolescents [1].

A possible neurological impact

These studies not only show that the effects of nicotine delivered by e-cigarettes are similar to those of smoked cigarettes, but they also highlight the particularities of e-cigarettes, namely their nicotine delivery system and the chemical aromas associated with them.

As is the case with cigarette smoke, the nicotine contained in the vapor of e-cigarettes manages to cross the barrier that usually protects the brain from any toxin coming from outside. The endothelial cells of the micro-blood vessels that make up this barrier are very sensitive to chemical variations in the brain environment; their alteration could lead to cognitive decline and microvascular dysfunction. These well-known consequences of long-term smoking are found in a very similar way with nicotine from e-cigarettes [2].

This impact on cognitive functions and memory is also highlighted by a study on an animal model, in mice exposed during gestation to e-cigarette vapor [3]. These experimental data in animals suggest potential consequences of vaping on the human fetus as well as on the neurological development of adolescents, whose brain is still in full formation [4].

Another study shows that e-cigarette vapor produces a stress response in neural stem cells, which could ultimately affect brain development [5].

Specific effects of nicotine exposure in adolescents

The consequences of brain exposure to nicotine are particularly sensitive in the neurological development of adolescents [6], which raises not only the question of access to e-cigarettes for this population, but also that of the concentration of nicotine in the inhaled vapor. The current trend is indeed towards increasing nicotine concentrations, particularly in pre-filled e-cigarettes such as Juul, which suggests an amplification of this neurological damage in the long term. The chemical components of the flavors present in e-liquids are also suspected of interfering at the microvascular level with the self-regulation mechanisms of the brain [7], which suggests a potential harmfulness of e-cigarettes on the brain, beyond the specific action of nicotine.

While all of these data deserve to be fully validated by other studies, these results highlight the cardiovascular repercussions of vaping and their impact on the brain and already allow us to affirm that "electronic cigarettes cannot be considered as safe products at the cardiovascular level" [8]. They also encourage us to adopt the greatest caution with regard to studies funded by the tobacco industry, which is doing its part to demonstrate the safety of vaping products.

Keywords: vaping, electronic cigarette, flavors, nicotine, adolescents, brain

©Tobacco Free Generation

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[1] Silva G, Accumulating Evidence Suggests E-Cigarettes Are Likely As Harmful To The Brain As Regular Smoking, Forbes. Published June 6, 2021, accessed June 9, 2021. [2] Kuntic M. et al., Short-term e-cigarette vapor exposure causes vascular oxidative stress and dysfunction: evidence for a close connection to brain damage and a key role of the phagocytic NADPH oxidase (NOX-2). Eur Heart J. 2020 Jul 7; 41(26): 2472–2483. [3] Church JS, Chace-Donahue F, Blum JL, Ratner JR, Zelikoff JT, Schwartzer JJ. Neuroinflammatory and behavioral outcomes measured in adult offspring of mice exposed prenatally to e-cigarette aerosols. About Health Perspective. 2020;128(4):47006. [4] Tobore TO, On the potential harmful effects of E-Cigarettes (EC) on the developing brain: The relationship between vaping-induced oxidative stress and adolescent/young adults social maladjustment. J Adolesc. 2019 Oct;76:202-209. [5] Zahedi A, Phandthong R, Chaili A, Leung S, Omaiye E, Talbot P, Mitochondrial Stress Response in Neural Stem Cells Exposed to Electronic Cigarettes. iScience. 2019 Jun 28;16:250-269. [6] Yuan M, Cross S, Loughlin S, Leslie F, Nicotine and the adolescent brain. J Physiol 593.16 (2015) pp 3397–3412. [7] Tobacco Free Generation, Toxicity of compounds formed in e-liquids? Published November 25, 2020, accessed June 9, 2021. [8] Skotsimara G, Antonopoulos AS, Oikonomou E, Siasos G, Ioakeimidis N, Tsalamandris S, Charalambous G, Galiatsatos N, Vlachopoulos C, Tousoulis D., Cardiovascular effects of electronic cigarettes: A systematic review and meta-analysis. Eur J Prev Cardiol 2019;26:1219–1228.National Committee Against Smoking |