Vaping is a slang term used to describe a method for inhaling tobacco or other herbs without literally burning them with a flame. Electric heating devices turn volatile chemicals within the tobacco or herb into a vapor (gaseous form of the chemical) that can be inhaled. Typically smokers of tobacco don’t draw the smoke of cigarettes or a pipe deeply into the lungs while smokers of marijuana do tend to inhale and hold the smoke. Either type of smoking does create toxins from the act of burning the herb/tobacco leaf.
Electric vaping cartridges heat a liquid mixture that may contain nicotine from tobacco or THC/CBD from marijuana possibly along with other chemicals to help keep the mixture mixed (emulsifying oils such as glycerine) or chemicals that add a flavor and/or odor. The goal of vaping was to reduce the health risks that are linked to carcinogens in tobacco or to the chemicals that are created during burning a substance (too many decorative candles in a poorly ventilated home can also be a health hazard). Unfortunately there have been health problems and even some deaths linked to vaping nicotine or cannabinoid containing vape products.
Health risks have been linked to the glycerine (exogenous lipoid pneumonia (ELP), a type of pneumonia caused by excess fats/lipids in lung cells) (2), however other health problems have also occurred. No one chemical has been found that can be linked to all of the health problems or deaths that have occurred. (1) In addition to the type of pneumonia attributed to the glycerine content, several of the chemicals used to add flavor to vape products have been linked to various negative health symptoms.
Cinnamon contains cinnamaldehyde which has been found to be a health risk in vape products. (7) Risks have also been linked to o-vanillin, found naturally in vanilla, and pentanedione (found in honey). Other potentially harmful chemicals were also a frequent problem when fifty flavored vape products were tested 92% were positive for diacetyl, acetylpropionyl, or acetoin. (9) Glycerine may be harmful as a fatty substance that doesn’t belong in the lungs but may also be acting as modulators or activators of TRPV channels. (glycerine/glycerol) (12) Butter flavorings use 2-3-Pentanedione which has already been associated with lung problems associated with microwave popcorn. (13)
More complex flavors include several flavoring chemicals in combination, and risk may also increase from combinations or increased total quantity of the chemicals used as flavorings. Products available for sale may not be subject to regulation or labeling requirements so what a vape liquid contains may not be available to a consumer or a medical professional.
Natural phytonutrients found in vanilla and cinnamon add fragrance and health benefits, however when inhaled deeply into the lungs they may be overactivating cells due to their ability to open channels through cell membrane walls which allows excess calcium to enter the cell, or through the membranes of mitochondria found within cells. Cinnamaldehyde and vanillin are both TRP channel activators. TRP channels are portals through the cell membrane wall or in the membrane of organelles within the cell such as mitochondria, the main energy producing part of every cell. The TRPA1 channel is a type associated with coughing and mucous production. (8) Ethyl vanillin activates TRPA1 channels (10) and more typically vanillin is known to activate TRPV channels (the V stands for vanilloid). (11)
Vitamin E content in vape mixtures has also been linked with health risks associated with vaping. (4) Vitamin E can act as a preservative against oxidation, or spoilage of the oil content in a mixture, and it may also act as a TRP channel modulator – affecting the ability of other chemicals to open TRP channels. Vitamin E might help keep them closed in some tested conditions. (5) Cannabinoids can also act as TRP channel activators. (6) The non-euphoria producing cannabinoid known as CBD activates TRPV1 channels and the euphoria producing cannabinoid in marijuana known as THC activates the TRPA1 channels. (11)
Normally the fragrance of foods is sensed within the nose. The tongue and the lungs have no scent receptors. The cinnamon smells fragrant in small amounts but sniff a large amount and you may sneeze and your nose will likely start dripping with extra mucous production. Extra mucous production is a protective mechanism to keep potentially harmful or irritating chemicals from being inhaled into the lungs.
Horseradish has a very pungent smell and hot pepper simply burns when eaten or when it gets on delicate mucous membranes and eating either will also cause increased mucous production and release – in other words – a runny nose. Horseradish and hot pepper also contain potent TRP channel activators – they are causing mucous to be released. Extra mucous production is normal for your nose, it can just drip or be blown out, but deep within your lungs too much mucous production can cause the lungs to overfill and it may lead to pneumonia or Chronic Obstructive Pulmonary Disease (COPD) also involves lungs that are too full of liquid. COPD patients are recommended to avoid use of e-cigarettes as they may increase the inflammatory response of COPD lung cells (3)
The simplest take home point might be to avoid flavors in vape products altogether – the lungs can’t smell them, neither can your tongue, only your nose can. Unless you are inhaling through your nose, where mucous membranes are designed to prevent entry of toxic chemicals and TRP channel activators, then it would likely be safest to avoid sweetened or flavored vape products and avoiding unregulated products helps reduce the risk of unknown ingredients present in unknown amounts. An article on Healthline includes a long list of specific chemicals found in vape products that may have health risks. The article reviews other known health risks and includes links to the research articles. See: Is Vaping Bad for You? And 12 Other FAQs. (9)
*Vaping is not recommended during pregnancy due to the health hazards that are known, and the many unknowns about the health risks to a developing baby.
- Vaping, Part 2: ELP, Pneumonia and Oils.
- Vaping, Part 3: Combined risks – oils and TRP channel activators.
Disclaimer: This information is provided for educational purposes within the guidelines of Fair Use. It is not intended to provide individual guidance. Please seek a health care provider for individualized health care guidance.
- Health Canada, Information Update – Health Canada warns of potential risk of pulmonary illness associated with vaping products, Oct. 11, 2019, email@example.com; https://www.newswire.ca/news-releases/information-update-health-canada-warns-of-potential-risk-of-pulmonary-illness-associated-with-vaping-products-867534807.html
- Viswam D, Trotter S, Burge PS, Walters GI, Respiratory failure caused by lipoid pneumonia from vaping e-cigarettes. BMJ Publishing Group Limited 2018 http://dx.doi.org/10.1136/bcr-2018-224350 , https://casereports.bmj.com/content/2018/bcr-2018-224350
- Heightened response to e-cigarettes in COPD, European Respiratory Society, https://openres.ersjournals.com/content/5/1/00192-2018
- Brueck H, Vaping is leading to a spate of lung injuries, comas, and death. Lung experts say oils like vitamin E may be partially to blame. Insider, Sep 19, 2019, https://www.insider.com/why-is-vaping-dangerous-for-your-lun
- Nazıroğlu M, Özgül C, Vitamin E modulates oxidative stress and protein kinase C activator (PMA)-induced TRPM2 channel gate in dorsal root ganglion of rats. C. J Bioenerg Biomembr (2013) 45: 541. https://doi.org/10.1007/s10863-013-9524-x https://link.springer.com/article/10.1007/s10863-013-9524-x
- Muller C, Morales P, Reggio PH. Cannabinoid Ligands Targeting TRP Channels. Front Mol Neurosci. 2019;11:487. Published 2019 Jan 15. doi:10.3389/fnmol.2018.00487 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6340993/
- Clapp PW, Lavrich KS, van Heusden CA, et al., Cinnamaldehyde in flavored e-cigarette liquids temporarily suppresses bronchial epithelial cell ciliary motility by dysregulation of mitochondrial function. American Journal of Physiology-Lung Cellular and Molecular PhysiologyVol. 316, No. 3, https://www.physiology.org/doi/abs/10.1152/ajplung.00304.2018?journalCode=ajplung
- Geppetti P, Patacchini R, Nassini R, Materazzi S, Cough: The Emerging Role of the TRPA1 Channel. Lung (2010) 188(Suppl 1): 63. https://doi.org/10.1007/s00408-009-9201-3 https://link.springer.com/article/10.1007/s00408-009-9201-3
- Is Vaping Bad for You? And 12 Other FAQs, Healthline https://www.healthline.com/health/is-vaping-bad-for-you
- Wu SW, Fowler DK, Shaffer FJ, Lindberg JEM, Peters JH. Ethyl Vanillin Activates TRPA1. J Pharmacol Exp Ther. 2017;362(3):368–377. doi:10.1124/jpet.116.239384 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5539581/
- Premkumar LS. Transient receptor potential channels as targets for phytochemicals. ACS Chem Neurosci. 2014;5(11):1117–1130. doi:10.1021/cn500094a https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4240255/
- Kahn-Kirby AH, Dantzker JLM, Apicella AJ, et al., Specific Polyunsaturated Fatty Acids Drive TRPV-Dependent Sensory Signaling In Vivo. Cell, Vol 119, Issue 6, 17 Dec. 2004, pp 889-900 https://www.sciencedirect.com/science/article/pii/S0092867404010475#!
- CDC – Flavorings-Related Lung Disease: Exposures to Flavoring Chemicals, NIOSH Workplace Safety and Health Topic, https://www.cdc.gov/niosh/topics/flavorings/exposure.html