|
On 23 May 2006, Donald Tashkin, M.D., Professor of Medicine at the David Geffen School of Medicine at UCLA in Los Angeles announced that the use of cannabis does not appear to increase the risk of developing lung cancer, or increase the risk of head and neck cancers, such as cancer of the tongue, mouth, throat, or esophagus.<ref name="Study Finds No Link Between Marijuana Use And Lung Cancer">{{cite news |url=http://www.sciencedaily.com/releases/2006/05/060526083353.htm |title=Study Finds No Link Between Marijuana Use And Lung Cancer |newspaper=Science Daily |date=2006-05-26 |accessdate=10-12-2011}}</ref> The study involved 2252 participants, with some of the most chronic marijuana smokers having smoked over 22,000 marijuana cigarettes.<ref name="Study Finds No Link Between Marijuana Use And Lung Cancer"/><ref name="Tobacco">{{cite news|url=http://www.mapinc.org/drugnews/v05/n1106/a09.html?275821|title=Marijuana Smoking Does Not Cause Lung Cancer|org=Anderson Valley Advertiser|author=Fred Gardner|date=2006-07-06}}</ref><ref name=tashkin1997>Tashkin, D. P., Simmons, M. S., Sherrill, D. L., and Coulson, A. H. 1997. . ''American Journal of Respiratory and Critical Care Medicine'' '''155'''(1): 141-148. Retrieved on 5 March 2007</ref><ref name="UCLA study">{{cite news |url=http://www.washingtonpost.com/wp-dyn/content/article/2006/05/25/AR2006052501729_pf.html |title=Study finds no marijuana-lung cancer link |publisher=Washington Post |date=2006-05-26 |accessdate=2006-07-13 |first=Marc |last=Kaufman}}</ref> The finding of Donald Tashkin, M.D., and his team of researchers in 2006 refined their earlier studies published in a Dec. 17th 2000 edition of the peer-reviewed journal Cancer Epidemiology Biomarker and Prevention.<ref>{{citation |url=http://www.sciencedaily.com/releases/1999/12/991220082058.htm |title=Researchers At UCLA's Jonsson Cancer Center Report Smoking Marijuana May Increase Risk Of Head And Neck Cancers |publisher=Sciencedaily.com |date=1999-12-20 |accessdate=2011-04-20}}</ref> Many opponents of marijuana incorrectly cite the original finding of UCLA Medical Center from 2000 as "proof" that marijuana leaves the users at higher risk for cancer of the lung, and cancerous tumors,<ref name=TumorGrowth>{{cite news|url=http://www.drugabuse.gov/MedAdv/00/NR6-20.html|title=Study Finds Marijuana Ingredient Promotes Tumor Growth, Impairs Anti-Tumor Defenses|org=Journal of Immunology|author=Dr. Steven M. Dubinett|date=July 2006}}</ref> even though the researchers at the UCLA Medical Center have revised their finding with a more in-depth study on the effects of the use of marijuana. This seemed to contradict assumptions made after some studies, like those from Dale Gieringer et al., which found that 118 carcinogens were produced when marijuana underwent combustion, and two carcinogens {2-Methyl-2, 4(2H-1-benzopyran-5-ol) & 5-azulene-3,8-dione} formed when marijuana underwent vaporization with the ].<ref name="Sarafian TA, Kouyoumjian S, Tashkin D, Roth MD 2002 171–9">{{cite journal |author=Sarafian TA, Kouyoumjian S, Tashkin D, Roth MD |title=Synergistic cytotoxicity of Delta(9)-tetrahydrocannabinol and butylated hydroxyanisole |journal=Toxicol. Lett. |volume=133 |issue=2-3 |pages=171–9 |year=2002 |month=July |pmid=12119125 |doi= 10.1016/S0378-4274(02)00134-0|url=http://linkinghub.elsevier.com/retrieve/pii/S0378427402001340}}</ref><ref name="Gieringer D., St. Laurent J., and Goodrich S.">{{cite journal |author=Gieringer D., St. Laurent J., and Goodrich S. |title=Cannabis Vaporizer Combines Efficient Delivery of THC with Effective Suppression of Pyrolytic Compounds |journal=Journal of Cannabis Therapeutics |volume= 4 |issue=1 |pages=7–27 |year=2008 |month=Oct |doi=10.1300/J175v04n01_02 |url= http://www.tandfonline.com/doi/abs/10.1300/J175v04n01_02}}</ref> To help explain this seemingly chemical proof of carcinogenicity inherent in the process of combustion, Tashkin noted that "one possible explanation for the new findings, he said, is that THC, a chemical in marijuana smoke, may encourage aging cells to die earlier and therefore be less likely to undergo cancerous transformation."<ref name="Study Finds No Link Between Marijuana Use And Lung Cancer"/> |
|
|
In a study of ten smokers with mild respiratory issues Hii et al. found evidence of lung disease in the form of severe bullae (fluid-filled, thin-walled blisters) of different shapes and sizes. Despite such lung disease, the patients' chest x-rays were normal and lung function was only mildly reduced in nearly half of the patients. The cannabis-smoking patient group was, on average, 41 years old—considerably younger than previously research tobacco-smoking patients with lung disease, who had an average age of between 62–67 years. The researchers conclude that the younger age of lung disease and poorer lung function may be due to different smoking patterns demonstrated in cannabis smokers,<ref>Hii, S.W., Tam, J.D.C., Thompson, B.R. & Naughton, M.T. (2008). Bullous lung disease due to marijuana. ''Respirology 13, 122-127''</ref> who have been found to inhale larger amounts of smoke, which is held in the lungs for longer periods of time.<ref>{{cite web|url=http://ncpic.org.au/ncpic/publications/factsheets/article/cannabis-and-tobacco-use// |title=NCPIC Cannabis and tobacco factsheet |publisher=Ncpic.org.au |date=2011-03-11 |accessdate=2011-04-20}}</ref> |
|