We caution the public against smoking marijuana because of the risks it poses to lung health.
Received Nov 30; Accepted Oct This article has been cited by other articles in PMC. Abstract More people are using the cannabis plant as modern basic and clinical science reaffirms and extends its medicinal uses. Concomitantly, concern and opposition to smoked medicine has occurred, in part due to the known carcinogenic consequences of smoking tobacco.
Are these reactions justified? While chemically very similar, there are fundamental differences in the pharmacological properties between cannabis and tobacco smoke.
Cannabis smoke contains cannabinoids whereas tobacco smoke contains nicotine. Available scientific data, that examines the carcinogenic properties of inhaling smoke and its biological consequences, suggests reasons why tobacco smoke, but not cannabis smoke, may result in lung cancer.
In addition to its high addiction potential [ 1 ], tobacco is causally associated with overdeaths yearly in the United States, and has a significant negative effect on health in general [ 2 ].
More specifically, overlung-related deaths in were attributed to tobacco smoke [ 3 ]. Comparable consequences would naturally be expected from cannabis smoking since the burning of plant material in the form of cigarettes generates a large variety of compounds that possess numerous biological activities [ 4 ].
While cannabis smoke has been implicated in respiratory dysfunction, including the conversion of respiratory cells to what appears to be a pre-cancerous state [ 5 ], it has not been causally linked with tobacco related cancers [ 6 ] such as lung, colon or rectal cancers.
|Learn About Marijuana: Factsheets: Marijuana and Tobacco Use||Tobacco Smoking Marijuana vs.|
Recently, Hashibe et al [ 7 ] carried out an epidemiological analysis of marijuana smoking and cancer. A connection between marijuana smoking and lung or colorectal cancer was not observed. These conclusions are reinforced by the recent work of Tashkin and coworkers [ 8 ] who were unable to demonstrate a cannabis smoke and lung cancer link, despite clearly demonstrating cannabis smoke-induced cellular damage.
Furthermore, compounds found in cannabis have been shown to kill numerous cancer types including: The effects of cannabinoids are complex and sometimes contradicting, often exhibiting biphasic responses.
For example, in contrast to the tumor killing properties mentioned above, low doses of THC may stimulate the growth of lung cancer cells in vitro [ 15 ].
The genotoxic effects of partially oxidized hydrocarbons created by burning either cannabis or tobacco have been widely examined as the likely source of genetic changes that lead to the carcinogenic state [ 16 ]. As a result, the medical potential of cannabis has been obscured by the potential negative impact of using a smoked medicine [ 17 ].
Those who deny the validity of "medical marijuana," cite that marijuana smoke contains four fold more tars than does tobacco smoke [ 18 ]. Nevertheless, smoking is often the preferred route of intake by medical cannabis users because rapid action allows self-titration [ 19 ].
Are the biological consequences of smoking cannabis and tobacco similar? Smoke from tobacco and cannabis contains many of the same carcinogens and tumor promoters [ 2021 ].
However, cannabis and tobacco have additional pharmacological activities, both receptor-dependent and independent, that result in different biological endpoints. Polycyclic aromatic hydrocarbons found in smoke are pro-carcinogens that are converted to carcinogens by the enzymatic activity of the cytochrome PA1 oxidase protein CYP1A1 gene product.
Benzo [a] pyrene is converted to its carcinogenic metabolite diol epoxide, which binds to specific hyper-mutable nucleotide sequences in the K-ras oncogene and p53 tumor suppressor [ 22 ]. Recent work by Roth et al. Thus, despite potentially higher levels of polycyclic aromatic hydrocarbons found in cannabis smoke compared to tobacco smoke dependent on what part of the plant is smokedthe THC present in cannabis smoke should exert a protective effect against pro-carcinogens that require activation.
In contrast, nicotine activates some CYP1A1 activities, thus potentially increasing the carcinogenic effects of tobacco smoke [ 24 ].Marijuana Smoke and Cancer Consequently, studies have so far failed to identify an association between cannabis smoke exposure and elevated risks of smoking-related cancers, such as cancers of the.
Additionally, researchers looking to study long-term marijuana use have had difficulty in finding people who regularly smoke marijuana but don’t also smoke tobacco cigarettes.
Marijuana users usually inhale more deeply and hold their breath longer than tobacco smokers do, which increases the lungs' exposure to carcinogenic smoke, so puff for puff, smoking marijuana increases the risk of cancer even more than smoking tobacco does.
A marijuana user poses a joint over some ground marijuana Nov. 4, , in Tempe, Ariz. (AP File Photo/Matt York) And another thing: cigarettes.
They’re all over the place in many films, markers of an era when smoking was far more common. The challenge of comparing marijuana smoke vs. tobacco some is more difficult because of various factors relevant to marijuana smoking.
Firstly, as mentioned earlier, many marijuana smokers use tobacco with marijuana, but other don’t. Social and Societal Stigmas of Cigarettes vs. Marijuana. Marijuana remains illegal for recreational use, though Alaska, California, Colorado, Hawaii, Maine, Montana, Nevada, Oregon, Vermont and Washington allow the use of marijuana for medical purposes, according to arteensevilla.com