Vaporizer (inhalation device)

A vaporizer or vaporiser, colloquially known as a vape, is a device used to vaporize substances for inhalation. Plant substances can be used, commonly cannabis, tobacco, or other herbs or blends of essential oil.^[1] However, they are most commonly filled with a combination propylene glycol, glycerin, and drugs such as nicotine (e.g. extract from tobacco) or tetrahydrocannabinol as a liquid solution.^[2]

A vaporization heat wand and vaporization chamber bowl used to deliver vapor through a water pipe

Vaporizers contain various forms of extraction chambers including straight bore, venturi, or sequential venturi, and are made of materials such as metal or glass. The extracted vapor may be collected in an inflatable bag, or inhaled directly through a hose or pipe. When used properly, cooler temperatures due to lack of combustion^[3] result in significantly more efficient extraction of the ingredients. Hence, the irritating and harmful effects of smoking are heavily reduced,^{[4][5][6][7][8]} as is its secondhand smoke.

Cannabis vaporizers

Cannabis flower is commonly consumed using a dry herb vaporizer. The cannabis may be heated in a chamber via indirect flame exposure or an electrical heating element, allowing users to inhale the resulting vapor. The temperatures reached are cooler than the combustion temperature of cannabis, which is around 230–315 °C (445–600 °F).^[9]

Vaporizing is more efficient than smoking, because approximately 30% of THC in cannabis or hashish cigarettes is destroyed by pyrolysis during smoking.^[10]

Cannabis is also consumed via the vaporization of cannabis concentrates or oils that have been extracted from the plant, commonly referred to as "dabbing". Users typically employ a torch to heat a small cup shaped quartz or titanium attachment on a bong before dabbing the oil onto the heated surface and inhaling the vapors through the bong.^[11] This route of consumption is generally much more potent than smoking or vaporizing marijuana flower due to the increased concentration of cannabinoids. Users typically report that the effects of dabbing are much more intense than regular cannabis, while also being shorter lived.^[12]

Cannabis concentrate is also commonly used in e-cigarette style vaporizer pens in the form of liquid containers known as cartridges. A battery connected to the atomizer is used to heat the cannabis oil, creating a vapor that is inhaled by the user. Cartridges typically contain different preparations of cannabis oil mixed with cannabinoids, terpenes, solvents (primarily Propylene glycol and Glycerol) used for thinning, fatty acids, and flavonoids. Natural or artificial terpenes are frequently added by manufacturers to enhance flavor, often using blends that mimic popular cannabis strains or sugary foods such as candy or pastries.^[13]

•  
  Vaporizer with water-cooling
•  
  A conduction-style vaporizer
•  
  A passive-convection "vaporization pipe" with flame filter
•  
  A man inhaling cannabis concentrate vapor from a dab rig
•  
  New York State Department of Health image showcasing a variety of THC vapes and packaging

Of the studies that have investigated cannabis vaporization, few have addressed the quality of the vapor extracted and delivered; instead, studies usually focus on the mode of usage of the vaporizers. However, those that have addressed vapor quality have demonstrated promising results. Such studies suggest that the absence of combustion results in an aerosol that contains significantly lower amounts of harmful substances found in smoke, such as tar, carbon monoxide, and carcinogenic compounds known as polynuclear aromatic hydrocarbons (PAH).^[14][9][15] One study found that cannabis smoke contains 111 compounds (including several carcinogenic PAHs) in addition to the cannabinoids, whereas only 3 additional compounds were identified in cannabis vapor, other than the cannabinoids.^[9] This suggests that the vaporization of cannabis may be a safer alternative to combusted cannabis.^[16] On the other hand, a study in the UK (where cannabis is illegal) found that some illicitly distributed cannabis vaporizers contained harmful levels of xylazine, an animal sedative which can lead to overdose.^[17]

E-cigarette vaporizers

Main article: Electronic cigarette

 

Various types of electronic cigarettes

An electronic cigarette is a handheld battery-powered vaporizer that simulates smoking by providing some of the behavioral aspects of smoking, including the hand-to-mouth action of smoking, but without combusting tobacco.^[18] Using an e-cigarette is known as "vaping" and the user is referred to as a "vaper."^[19] Instead of cigarette smoke, the user inhales an aerosol, commonly called vapor.^[20] E-cigarettes typically have a heating element that atomizes a liquid solution called e-liquid.^[21] E-cigarettes may be automatically activated by taking a puff;^[22] others turn on manually by pressing a button.^[19] Some e-cigarettes look like traditional cigarettes,^[23] but they come in many variations.^[19] Most versions are reusable, though some are disposable.^[24] There are first-generation,^[25] second-generation,^[26] third-generation,^[27] and fourth-generation devices.^[28] E-liquids usually contain propylene glycol, glycerin, nicotine, flavorings, additives, and differing amounts of contaminants.^[29] E-liquids are also sold without propylene glycol,^[30] nicotine,^[31] or flavors. ^[32]

The benefits and the health risks of e-cigarettes are uncertain.^[33][34][35] There is tentative evidence they may help people quit smoking,^[36] although they have not been proven to be more effective than smoking cessation medicine.^[37] There is concern with the possibility that non-smokers and children may start nicotine use with e-cigarettes at a rate higher than anticipated than if they were never created.^[38] Following the possibility of nicotine addiction from e-cigarette use, there is concern children may start smoking cigarettes.^[38] Youth who use e-cigarettes are more likely to go on to smoke cigarettes.^[39][40] Their part in tobacco harm reduction is unclear,^[41] while another review found they appear to have the potential to lower tobacco-related death and disease.^[42] Regulated US Food and Drug Administration nicotine replacement products may be safer than e-cigarettes,^[41] but e-cigarettes are generally seen as safer than combusted tobacco products.^[43][44] It is estimated their safety risk to users is similar to that of smokeless tobacco.^[45] The long-term effects of e-cigarette use are unknown.^[46][47][48] The risk from serious adverse events was reported in 2016 to be low.^[49] Less serious adverse effects include abdominal pain, headache, blurry vision,^[50] throat and mouth irritation, vomiting, nausea, and coughing.^[51] Nicotine itself is associated with some health harms.^[52] In 2019 and 2020, an outbreak of severe lung illness throughout the US has been linked to the use of contaminated black market THC vape cartridges.^[53]

Other drug

Vaporizers can be used to inhale other recreational drugs as well. A wide variety can be consumed this way, either dissolved in e-liquid or vaporized directly.^[54] The use of e-cigarettes to inhale the psychedelic drug DMT has been reported.^[55]

Medical vaporizers

Studies have shown that vaporizing cannabis exposes the user to lower levels of harmful substances than smoking cannabis.^{[9][56][57][58]} These findings are important for it is estimated that 10–20% of patients with chronic pain, multiple sclerosis, epilepsy, and HIV/AIDS have admitted to smoking cannabis for therapeutic purposes. For patients, a study found that smoking cannabis sativa reduced daily pain by 34%, a statistically significant amount.^[59]

In a study published in the Journal of Psychopharmacology in May 2008, it was stated that vaporizers were a "suitable method for the administration of THC".^[60] A 2007 study by the University of California, San Francisco, published in the Journal of the American Academy of Neurology, found that "there was virtually no exposure to harmful combustion products using the vaporizing device".^[7] A 2006 study performed by researchers at Leiden University found that vaporizers were "safe and effective cannabinoid delivery system(s)". The study stated that the amount of THC delivered by vaporizers were equivalent to the amount delivered by smoking.^[58] Because of those studies and other studies, vaporizers are considered medically sound devices for delivering THC.^[14]

Efficiency

The proposed factors affecting output include:^[9][58]

• Temperature
• Specimen density
• Weight, content of water and essential oils
• Consistency of material in the filling chamber
• Storage time of the vapor
• Inhalation method (breathing technique)

Not all those have been scientifically tested. Research using vaporizers found the delivery efficiency highest at around 226 °C (439 °F), falling to about half efficiency at 150 to 180 °C (302 to 356 °F) depending on material.^[58] The purest preparations produced the highest efficiencies, about 56% for pure THC versus 29% for plant material (female flower tops) with 12% THCA content. Besides THC, several other cannabinoids as well as a range of other plant components including terpenoids were detected in the plant material. Using pure THC in the vaporizer, no degradation products (delta-8-THC (D8-THC), cannabinol (CBN), or unknown compounds) were detected by HPLC analysis.^[58] The longer vapor is stored, the more THC is lost as it condenses on the surface of the vaporizer or the balloon. This loss may be negligible over a few minutes but may exceed 50% after 90 minutes.^[58] The Leiden University study found that as much as 30–40% of inhaled THC was not absorbed by the lungs but simply exhaled. However, they did not find large individual differences in the amounts exhaled.^[58]

Culinary application

Vaporizers are sometimes used by chefs as a method of applying controlled heat to herbs and spices to release flavors that are otherwise difficult to titrate or apply, or that might be spoiled by overheating during cooking.^[61][62][63] Grant Achatz, chef-proprietor of Alinea in Chicago, "uses the aroma-filled bags as place-mats, punctured when plates are placed in front of the customer".^[61]

See also

 

Wikimedia Commons has media related to Vaporizers.

 

Look up vaporizer in Wiktionary, the free dictionary.

• Anesthetic vaporizer
• Aromatherapy
• Chasing the dragon
• Eagle Bill
• Nebulizer

Bibliography

• Wilder, Natalie; Daley, Claire; Sugarman, Jane; Partridge, James (April 2016). "Nicotine without smoke: Tobacco harm reduction". UK: Royal College of Physicians. pp. 1–191.
• "Electronic nicotine delivery systems" (PDF). World Health Organization. 21 July 2014. pp. 1–13.

References

1. Stefaniak, Aleksandr B.; LeBouf, Ryan F.; Ranpara, Anand C.; Leonard, Stephen S. (2021). "Toxicology of flavoring- and cannabis-containing e-liquids used in electronic delivery systems". Pharmacology & Therapeutics. 224: 107838. doi:10.1016/j.pharmthera.2021.107838. ISSN 0163-7258. PMC 8251682. PMID 33746051.
2. Li, Liqiao; Lee, Eon S.; Nguyen, Charlene; Zhu, Yifang (2020). "Effects of propylene glycol, vegetable glycerin, and nicotine on emissions and dynamics of electronic cigarette aerosols". Aerosol Science and Technology: The Journal of the American Association for Aerosol Research. 54 (11): 1270–1281. Bibcode:2020AerST..54.1270L. doi:10.1080/02786826.2020.1771270. ISSN 0278-6826. PMC 7590927. PMID 33116348.
3. Stephen A. Greene (2002). Veterinary Anesthesia and Pain Management Secrets. Elsevier Health Sciences. ISBN 978-1560534426.
4. Earleywine M, Barnwell SS (2007). "Decreased respiratory symptoms in cannabis users who vaporize". Harm Reduction Journal. 4: 11. doi:10.1186/1477-7517-4-11. PMC 1853086. PMID 17437626.
5. . www.aids.org. Archived from the original on 2010-07-18. Retrieved 2008-07-28.
6. Grotenhermen F (June 2001). "Harm Reduction Associated with Inhalation and Oral Administration of Cannabis and THC". Journal of Cannabis Therapeutics. 1 (3 & 4): 133–152. doi:10.1300/J175v01n03_09.
7. Abrams DI, Vizoso HP, Shade SB, Jay C, Kelly ME, Benowitz NL (November 2007). "Vaporization as a smokeless cannabis delivery system: a pilot study" (PDF). Clinical Pharmacology and Therapeutics. 82 (5): 572–578. doi:10.1038/sj.clpt.6100200. PMID 17429350. S2CID 14629288.
8. "The Centennial Celebration – Washington, D.C. September 13–17, 1948". Science. 108 (2800): 205–206. August 1948. doi:10.1126/science.108.2800.205. PMID 17821306.
9. Gieringer, Dale; St. Laurent, Joseph; Goodrich, Scott (9 February 2004). "Cannabis Vaporizer Combines Efficient Delivery of THC with Effective Suppression of Pyrolytic Compounds" (PDF). Journal of Cannabis Therapeutics. 4 (1): 7–27. doi:10.1300/J175v04n01_02. Retrieved June 20, 2010.
10. Marilyn A. Huestis; Michael L. Smith (2007), "Human Cannabinoid Pharmacokinetics and Interpretation of Cannabinoid Concentrations in Biological Fluids and Tissues", in Mahmoud A. ElSohly (ed.), Marijuana and the Cannabinoids, Humana Press, pp. 205–235
11. "Vaping & Marijuana Concentrates" (PDF). Drug Enforcement Administration. 2020. Retrieved 2023-10-28.
12. Chaiton, Michael; Kundu, Anasua; Rueda, Sergio; Di Ciano, Patricia (2021-08-26). "Are vaporizers a lower-risk alternative to smoking cannabis?". Canadian Journal of Public Health = Revue Canadienne de Santé Publique. 113 (2): 293–296. doi:10.17269/s41997-021-00565-w. ISSN 0008-4263. PMC 8975973. PMID 34448130.
13. Guo, Weihong; Vrdoljak, Gordon; Liao, Ven-Chi; Moezzi, Bahman (21 June 2021). "Major Constituents of Cannabis Vape Oil Liquid, Vapor and Aerosol in California Vape Oil Cartridge Samples". Frontiers in Chemistry. 9. Front Chem.: 694905. doi:10.3389/fchem.2021.694905. PMC 8333608. PMID 34368078.
14. Gieringer DH (June 2001). "Cannabis 'Vaporization'". Journal of Cannabis Therapeutics. 1 (3 & 4): 153–170. doi:10.1300/J175v01n03_10.
15. Abrams, D. I.; Vizoso, H. P.; Shade, S. B.; Jay, C.; Kelly, M. E.; Benowitz, N. L. (2007). "Vaporization as a Smokeless Cannabis Delivery System: A Pilot Study". Clinical Pharmacology & Therapeutics. 82 (5): 572–578. doi:10.1038/sj.clpt.6100200. ISSN 1532-6535. PMID 17429350. S2CID 14629288.
16. Loflin, Mallory; Earleywine, Mitch (2015). "No smoke, no fire: What the initial literature suggests regarding vapourized cannabis and respiratory risk". Canadian Journal of Respiratory Therapy. 51 (1): 7–9. ISSN 1205-9838. PMC 4456813. PMID 26078621.
17. Hall, Rachel (2024-04-10). "Animal tranquilliser found in cannabis vapes and illicit sedatives in UK". The Guardian. ISSN 0261-3077. Retrieved 2024-04-10.
18. Caponnetto, Pasquale; Campagna, Davide; Papale, Gabriella; Russo, Cristina; Polosa, Riccardo (2012). "The emerging phenomenon of electronic cigarettes". Expert Review of Respiratory Medicine. 6 (1): 63–74. doi:10.1586/ers.11.92. ISSN 1747-6348. PMID 22283580. S2CID 207223131.
19. Orellana-Barrios, Menfil A.; Payne, Drew; Mulkey, Zachary; Nugent, Kenneth (2015). "Electronic cigarettes-a narrative review for clinicians". The American Journal of Medicine. 128 (7): 674–81. doi:10.1016/j.amjmed.2015.01.033. ISSN 0002-9343. PMID 25731134.
20. Cheng, T. (2014). "Chemical evaluation of electronic cigarettes". Tobacco Control. 23 (Supplement 2): ii11–ii17. doi:10.1136/tobaccocontrol-2013-051482. ISSN 0964-4563. PMC 3995255. PMID 24732157.
21. Weaver, Michael; Breland, Alison; Spindle, Tory; Eissenberg, Thomas (2014). "Electronic Cigarettes". Journal of Addiction Medicine. 8 (4): 234–240. doi:10.1097/ADM.0000000000000043. ISSN 1932-0620. PMC 4123220. PMID 25089953.
22. Rahman, Muhammad; Hann, Nicholas; Wilson, Andrew; Worrall-Carter, Linda (2014). "Electronic cigarettes: patterns of use, health effects, use in smoking cessation and regulatory issues". Tobacco Induced Diseases. 12 (1): 21. doi:10.1186/1617-9625-12-21. PMC 4350653. PMID 25745382.
23. Pepper, J. K.; Brewer, N. T. (2013). "Electronic nicotine delivery system (electronic cigarette) awareness, use, reactions and beliefs: a systematic review". Tobacco Control. 23 (5): 375–384. doi:10.1136/tobaccocontrol-2013-051122. ISSN 0964-4563. PMC 4520227. PMID 24259045.
24. Drope, Jeffrey; Cahn, Zachary; Kennedy, Rosemary; Liber, Alex C.; Stoklosa, Michal; Henson, Rosemarie; Douglas, Clifford E.; Drope, Jacqui (2017). "Key issues surrounding the health impacts of electronic nicotine delivery systems (ENDS) and other sources of nicotine". CA: A Cancer Journal for Clinicians. 67 (6): 449–471. doi:10.3322/caac.21413. ISSN 0007-9235. PMID 28961314.
25. Bhatnagar, A.; Whitsel, L. P.; Ribisl, K. M.; Bullen, C.; Chaloupka, F.; Piano, M. R.; Robertson, R. M.; McAuley, T.; Goff, D.; Benowitz, N. (24 August 2014). "Electronic Cigarettes: A Policy Statement From the American Heart Association". Circulation. 130 (16): 1418–1436. doi:10.1161/CIR.0000000000000107. PMC 7643636. PMID 25156991.
26. Hayden McRobbie (2014). "Electronic cigarettes" (PDF). National Centre for Smoking Cessation and Training. pp. 1–16.
27. Farsalinos KE, Spyrou A, Tsimopoulou K, Stefopoulos C, Romagna G, Voudris V (2014). "Nicotine absorption from electronic cigarette use: Comparison between first and new-generation devices". Scientific Reports. 4: 4133. Bibcode:2014NatSR...4E4133F. doi:10.1038/srep04133. PMC 3935206. PMID 24569565.
28. Konstantinos Farsalinos. (PDF). gfn.net.co. Global Forum on Nicotine. Archived from the original (PDF) on 8 July 2015. Retrieved 23 September 2015.
29. England, Lucinda J.; Bunnell, Rebecca E.; Pechacek, Terry F.; Tong, Van T.; McAfee, Tim A. (2015). "Nicotine and the Developing Human". American Journal of Preventive Medicine. 49 (2): 286–93. doi:10.1016/j.amepre.2015.01.015. ISSN 0749-3797. PMC 4594223. PMID 25794473.
30. Oh, Anne Y.; Kacker, Ashutosh (December 2014). "Do electronic cigarettes impart a lower potential disease burden than conventional tobacco cigarettes?: Review on e-cigarette vapor versus tobacco smoke". The Laryngoscope. 124 (12): 2702–2706. doi:10.1002/lary.24750. PMID 25302452. S2CID 10560264.
31. Leduc, Charlotte; Quoix, Elisabeth (2016). "Is there a role for e-cigarettes in smoking cessation?". Therapeutic Advances in Respiratory Disease. 10 (2): 130–135. doi:10.1177/1753465815621233. ISSN 1753-4658. PMC 5933562. PMID 26668136.
32. Wilder 2016, p. 82.
33. Ebbert, Jon O.; Agunwamba, Amenah A.; Rutten, Lila J. (2015). "Counseling Patients on the Use of Electronic Cigarettes". Mayo Clinic Proceedings. 90 (1): 128–134. doi:10.1016/j.mayocp.2014.11.004. ISSN 0025-6196. PMID 25572196.
34. Siu, AL (22 September 2015). "Behavioral and Pharmacotherapy Interventions for Tobacco Smoking Cessation in Adults, Including Pregnant Women: U.S. Preventive Services Task Force Recommendation Statement". Annals of Internal Medicine. 163 (8): 622–34. doi:10.7326/M15-2023. PMID 26389730.
35. Harrell, PT; Simmons, VN; Correa, JB; Padhya, TA; Brandon, TH (4 June 2014). "Electronic Nicotine Delivery Systems ("E-cigarettes"): Review of Safety and Smoking Cessation Efficacy". Otolaryngology–Head and Neck Surgery. 151 (3): 381–393. doi:10.1177/0194599814536847. PMC 4376316. PMID 24898072.
36. McRobbie, Hayden; Bullen, Chris; Hartmann-Boyce, Jamie; Hajek, Peter; McRobbie, Hayden (2014). "Electronic cigarettes for smoking cessation and reduction". The Cochrane Database of Systematic Reviews. 12 (12): CD010216. doi:10.1002/14651858.CD010216.pub2. hdl:2292/27824. PMID 25515689.
37. McDonough, Mike (2015). "Update on medicines for smoking cessation". Australian Prescriber. 38 (4): 106–111. doi:10.18773/austprescr.2015.038. ISSN 0312-8008. PMC 4653977. PMID 26648633.
38. WHO 2014, p. 6.
39. "E-Cigarette Use Among Youth and Young Adults A Report of the Surgeon General: Fact Sheet" (PDF). Surgeon General of the United States. 2016.  This article incorporates text from this source, which is in the public domain.
40. Stratton 2018, p. Summary, 16. sfn error: no target: CITEREFStratton2018 (help)
41. Drummond, MB; Upson, D (February 2014). "Electronic cigarettes. Potential harms and benefits". Annals of the American Thoracic Society. 11 (2): 236–42. doi:10.1513/annalsats.201311-391fr. PMC 5469426. PMID 24575993.
42. M., Z.; Siegel, M (February 2011). "Electronic cigarettes as a harm reduction strategy for tobacco control: a step forward or a repeat of past mistakes?". Journal of Public Health Policy. 32 (1): 16–31. doi:10.1057/jphp.2010.41. PMID 21150942.
43. Knorst, Marli Maria; Benedetto, Igor Gorski; Hoffmeister, Mariana Costa; Gazzana, Marcelo Basso (2014). "The electronic cigarette: the new cigarette of the 21st century?". Jornal Brasileiro de Pneumologia. 40 (5): 564–572. doi:10.1590/S1806-37132014000500013. ISSN 1806-3713. PMC 4263338. PMID 25410845.
44. Burstyn, Igor (9 January 2014). "Peering through the mist: systematic review of what the chemistry of contaminants in electronic cigarettes tells us about health risks". BMC Public Health. 14 (1): 18. doi:10.1186/1471-2458-14-18. ISSN 1471-2458. PMC 3937158. PMID 24406205.
45. Caponnetto P; Russo C; Bruno CM; Alamo A; Amaradio MD; Polosa R. (Mar 2013). "Electronic cigarette: a possible substitute for cigarette dependence". Monaldi Archives for Chest Disease. 79 (1): 12–19. doi:10.4081/monaldi.2013.104. PMID 23741941.
46. Hartmann-Boyce, Jamie; McRobbie, Hayden; Lindson, Nicola; Bullen, Chris; Begh, Rachna; Theodoulou, Annika; Notley, Caitlin; Rigotti, Nancy A.; Turner, Tari; Butler, Ailsa R.; Fanshawe, Thomas R. (2021-04-29). "Electronic cigarettes for smoking cessation". The Cochrane Database of Systematic Reviews. 4 (8): CD010216. doi:10.1002/14651858.CD010216.pub5. ISSN 1469-493X. PMC 8092424. PMID 33913154.
47. Brady, Benjamin R.; De La Rosa, Jennifer S.; Nair, Uma S.; Leischow, Scott J. (2019). "Electronic Cigarette Policy Recommendations: A Scoping Review". American Journal of Health Behavior. 43 (1): 88–104. doi:10.5993/AJHB.43.1.8. ISSN 1087-3244. PMID 30522569. S2CID 54566712.
48. Bals, Robert; Boyd, Jeanette; Esposito, Susanna; Foronjy, Robert; Hiemstra, Pieter S.; Jiménez-Ruiz, Carlos A.; Katsaounou, Paraskevi; Lindberg, Anne; Metz, Carlos; Schober, Wolfgang; Spira, Avrum; Blasi, Francesco (2019). "Electronic cigarettes: a task force report from the European Respiratory Society". European Respiratory Journal. 53 (2): 1801151. doi:10.1183/13993003.01151-2018. ISSN 0903-1936. PMID 30464018.
49. Paley, Grace L.; Echalier, Elizabeth; Eck, Thomas W.; Hong, Augustine R.; Farooq, Asim V.; Gregory, Darren G.; Lubniewski, Anthony J. (2016). "Corneoscleral Laceration and Ocular Burns Caused by Electronic Cigarette Explosions". Cornea. 35 (7): 1015–1018. doi:10.1097/ICO.0000000000000881. ISSN 0277-3740. PMC 4900417. PMID 27191672.
50. Breland, Alison B.; Spindle, Tory; Weaver, Michael; Eissenberg, Thomas (2014). "Science and Electronic Cigarettes". Journal of Addiction Medicine. 8 (4): 223–233. doi:10.1097/ADM.0000000000000049. ISSN 1932-0620. PMC 4122311. PMID 25089952.
51. Grana, R; Benowitz, N; Glantz, SA (13 May 2014). "E-cigarettes: a scientific review". Circulation. 129 (19): 1972–86. doi:10.1161/circulationaha.114.007667. PMC 4018182. PMID 24821826.
52. Edgar, Julie (12 November 2013). "E-Cigarettes: Expert Q&A With the CDC". WebMD.
53. "Outbreak of Lung Illness Associated with Using E-cigarette Products". Centers for Disease Control and Prevention. 28 January 2020.  This article incorporates text from this source, which is in the public domain.
54. Varlet V (December 2016). "Drug Vaping: From the Dangers of Misuse to New Therapeutic Devices". Toxics. 4 (4): 29. doi:10.3390/toxics4040029. PMC 5606648. PMID 29051432.
55. Power M (2020-06-05). "I Sell DMT Vape Pens So People Can 'Break Through' at Their Own Speed". www.vice.com. Retrieved 2020-07-12.
56. "Marijuana Vaporizer Provides Same Level Of THC, Fewer Toxins, Study Shows", Official Journal of the American Academy of Neurology (summarized by Science Daily) (2007-05-16)". Sciencedaily.com. 2007-05-16. Retrieved 2011-02-23.
57. "Cal NORML/MAPS Study Shows Vaporizer Can Drastically Reduce Toxins in Marijuana Smoke". Canorml.org. Retrieved 2011-02-23.
58. Hazekamp A, Ruhaak R, Zuurman L, van Gerven J, Verpoorte R (June 2006). "Evaluation of a vaporizing device (Volcano) for the pulmonary administration of tetrahydrocannabinol". Journal of Pharmaceutical Sciences. 95 (6): 1308–17. doi:10.1002/jps.20574. PMID 16637053.
59. Barohn, Richard (2013). Peripheral Neuropathies, An Issue of Neurologic Clinics. Elsevier. ISBN 978-1455771226.
60. Zuurman L; Roy C; Schoemaker RC; et al. (September 2008). "Effect of intrapulmonary tetrahydrocannabinol administration in humans". Journal of Psychopharmacology. 22 (7): 707–16. doi:10.1177/0269881108089581. PMID 18515447. S2CID 6094814.
61. Bob Gledhill (22 August 2007). "Alinea restaurant uses Volcano as flavorizer". Caterersearch.com. Retrieved 2011-02-23.
62. "Tools for creating aromatic flavors". Chow.com. 2007-01-18. Retrieved 2011-02-23.
63. . Rimag.com. Archived from the original on 2009-01-24. Retrieved 2011-02-23.