Why Smoke Cannabis? 

Smoking cannabis is the most popular form of consumption due to its rapid onset and easy dose titration. Both of these premises makes smoking the ideal delivery mechanism for cannabis worldwide, despite some apparent health risks.  There is quite a range of methods to consume cannabis from edibles, vaping, transdermal and inhalation. Nevertheless, to most end-users, smoking is king. 

A comprehensive review of why one should use cannabis is a little beyond the scope of this summary (I mean, you’re here already looking to learn more about our filter, therefore, you already know about the benefits of cannabis), however, Dr. Sulak’s review is a great place to start. Mouhamed et al. also provides an excellent summary.

Given the many health benefits associated with cannabis use, wouldn’t it be nice to have a way to smoke cannabis in an individualized dosing regimen without having to worry about the “tar”, ash and other contaminants that routinely accompany smoking cannabis through a bong?

References:
[1] Carter GT, Weydt P, Kyashna-Tocha M, Abrams DI. Medicinal cannabis: rational guidelines for dosing. IDrugs. 2004 May;7(5):464-70. PMID: 15154108
[2] Backes, M. (2014). Cannabis pharmacy: the practical guide to medical marijuana. New York: Black Dog & Leventhal Publishers
[3] https://healer.com/cbd-cannabis-dosage-guide-project-cbd-interview-with-dr-sulak/ (accessed 11/2020)
[4] Grotenhermen, Franjo. (2001). Harm Reduction Associated with Inhalation and Oral Administration of Cannabis and THC. Journal of Cannabis Therapeutics. 1. 10.1300/J175v01n03_09.
[5] https://healer.com/the-health-effects-of-cannabis/ (accessed 11/2020)
[6] Mouhamed, Y., Vishnyakov, A., Qorri, B., Sambi, M., Frank, S. S., Nowierski, C., Lamba, A., Bhatti, U., & Szewczuk, M. R. (2018). Therapeutic potential of medicinal marijuana: an educational primer for health care professionals. Drug, healthcare and patient safety, 10, 45–66. https://doi.org/10.2147/DHPS.S158592

What is "Tar"?

"Tar” as related to smoking is defined by the Federal Trade Commission (FTC) as well as scientific literature as the total particulate matter minus nicotine and water delivered from commercial cigarettes that are smoked according to a standardized procedure.  

There is something to be noted regarding the similarities of the smoke contents between marijuana and cigarette smoke, namely, that aside from the nicotine content in tobacco smoke and THC content in marijuana smoke, that their smoke profiles are nearly identical.  

Both processes involve burning a leafy material, which produces a host of substances that are known to cause significant harmful health effects. In addition to the same carcinogenic properties, marijuana smoke contains four times the tar of cigarette smoke and the smoking profile/habits of cannabis users fully exposes them to that increased tar content. There is still mixed data regarding the link between marijuana smoke and lung cancer, however, the most recent evidence is concerning.

References:

[1] Rose JE, Wu T-C, Djahed B, Tashkin DP. Noninvasive measurements of smokers’ tar and nicotine intake. Behavioral Research Methods, Instruments and Computers 1987; 19:295 – 9. [2] Tashkin DP. Effects of marijuana smoking on the lung. Ann Am Thorac Soc. 2013 Jun;10(3):239-47. doi: 10.1513/AnnalsATS.201212-127FR. PMID: 23802821.
[3] Sheehan TJ, Hamnett HJ, Beasley R, Fitzmaurice PS. Chemical and physical variations of cannabis smoke from a variety of cannabis samples in New Zealand. Forensic Sciences Research. 2019; 4 (2): 168 – 178.
[4] Zhang LR, Morgenstern H, Greenland S, et al. Cannabis smoking and lung cancer risk: pooled analysis in the International Lung Cancer Consortium. Int J Cancer. 2015;136:894–903.
[5] Aldington S, Harwood M, Cox B, et al. Cannabis use and risk of lung cancer: a case-control study. Eur Resp J. 2008;31:280–286.
[6] Graves, B.M., Johnson, T.J., Nishida, R.T. et al. Comprehensive characterization of mainstream marijuana and tobacco smoke. Sci Rep 10, 7160 (2020). https://doi.org/10.1038/s41598-020-63120-6.
[7] Moir D, Rickert WS, Levasseur G, Larose Y, Maertens R, White P, Desjardins S. A comparison of mainstream and sidestream marijuana and tobacco cigarette smoke produced under two machine smoking conditions. Chem Res Toxicol. 2008 Feb;21(2):494-502. doi: 10.1021/tx700275p. Epub 2007 Dec 7. PMID: 18062674.
[8] Maertens RM, White PA, Rickert W, Levasseur G, Douglas GR, Bellier PV, McNamee JP, Thuppal V, Walker M, Desjardins S. The genotoxicity of mainstream and sidestream marijuana and tobacco smoke condensates. Chem Res Toxicol. 2009 Aug;22(8):1406-14. doi: 10.1021/tx9000286. PMID: 19947653. [9] Dryburgh LM, Bolan NS, Grof CPL, Galettis P, Schneider J, Lucas CJ, Martin JH. Cannabis contaminants: sources, distribution, human toxicity and pharmacologic effects. Br J Clin Pharmacol. 2018 Nov;84(11):2468-2476. doi: 10.1111/bcp.13695. Epub 2018 Aug 1. PMID: 29953631; PMCID: PMC6177718.
[10] Carter GT, Weydt P, Kyashna-Tocha M, Abrams D.I. Medicinal Cannabis: Rational guidelines for dosing. IDrugs, 2004; 7 (5), 464 – 470.
[11] Fehr KO, Kalant H. Analysis of cannabis smoke under different combustion conditions. Canadian Journal of Physiology and Pharmacology.1972; 50:761 – 767. https://doi.org/10.1139/y72-111.
[12] Russo EB. Current Therapeutic Cannabis Controversies and Clinical Trial Design Issues. Front Pharmacol. 2016 Sep 14;7:309. doi: 10.3389/fphar.2016.00309. PMID: 27683558; PMCID: PMC5022003.
[13] Wu TC, Tashkin DP, Djahed B, Rose JE. Pulmonary hazards of smoking marijuana as compared with tobacco. N Engl J Med. 1988 Feb 11;318(6):347-51. doi: 10.1056/NEJM198802113180603. PMID: 3340105.
[14] Gieringer D. Marijuana Water Pipe and Vaporizer Study. MAPS Newsletter. Vol 6 #3, 1996.