# Not even the straight dope on dope (Still smokin' - 14Apr2006) **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [April 14, 2006, 1:51pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658 "2006-04-14T13:51:15Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![II\_Gyan\_II](https://avatars.discourse-cdn.com/v4/letter/i/bbe5ce/32.png) [@II\_Gyan\_II](https://boards.straightdope.com/u/II_Gyan_II)\ **Post date:** [April 14, 2006, 1:51pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/1 "2006-04-14T13:51:15Z")
This latest [column](http://www.straightdope.com/columns/060414.html) about marijuana is more or less OK, but could have used some up to date cites. > [@](#): > > Fact is, however, that smoking large amounts of potent marijuana makes some people go nuts. One study (Chopra and Smith, 1974) told of 200 Calcutta psychiatric patients hospitalized in the 60s for psychotic symptoms after major herb intake, including hallucinations, amnesia, paranoia, etc. In this 2006 article, he’s citing a 1974 study?!? There have been quite a few longitudinal studies conducted since then. In fact, in the last few years, there have been a torrent of studies warning about cannabis-psychosis link. Prompted by these studies, the British Home Secretary requested the British Parliament’s Advisory Council on the Misuse of Drugs to prepare a report on the state of the research. I’ll quote from that Dec-2005 [report](http://www.drugs.gov.uk/publication-search/acmd/cannabis-reclass-2005) … > [@ACMD Report](#): > > Over the past few years, there has been growing concern as to whether cannabis use might precipitate chronic, or enduring, psychotic illnesses, including schizophrenia. In view of the ability of cannabis to precipitate relapse in individuals with established schizophrenia (see paragraph 4.4), it is clearly a biologically plausible hypothesis. However, research in this area is fraught with problems of both study design and interpretation. > … > Because schizophrenia is comparatively uncommon, most of the studies on the effects of cannabis on mental health have used the presence of psychotic symptoms to study the effects of the drug. It is important to note that the conditions described in the literature as schizophreniform psychoses and psychotic symptoms do not necessarily lead to the longterm disability that is so common with schizophrenia. > … > Studies have, inevitably, been observational. But exposure, followed by the development of psychotic symptoms, is not necessarily causal. For example, the onset of schizophrenia usually occurs in the late teens or early twenties; and it is at that age that cannabis use is most prevalent. A temporal association – which is not necessarily a causal one – is therefore inevitable. > … > There are differences between studies in the methods of detection of psychotic symptoms (see paragraph 4.8). Only one study (11) has used the appropriate measures, and has had the statistical power, to assess whether cannabis use precedes the onset of an illness that meets the full diagnostic criteria for schizophrenia. Others with smaller numbers of subjects have sought information about the frequency of schizophreniform or other psychotic illnesses, and the presence of psychotic symptoms. > … > For individuals, the current evidence suggests, at worst, that using cannabis increases the lifetime risk of developing schizophrenia by 1%. Some individuals are at higher risk than others for developing schizophrenia from the use of cannabis, but there is currently no means by which these individuals can be identified > [@](#): > > Twenty years ago the realist’s view of pot was that, despite what 60s romantics liked to think, the stuff in some ways combined the worst features of alcohol and tobacco: it could get you dangerously wasted, and it might cause lung cancer. Re: lung cancer - there have been a few large studies about the marijuana-cancer link. This [review](http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16054989&query_hl=12&itool=pubmed_docsum) is a good summary: > [@Cannabis-cancer review](#): > > In the cohort studies, increased risks of lung or colorectal cancer due to marijuana smoking were not observed, but increased risks of prostate and cervical cancers among non-tobacco smokers, as well as adult-onset glioma among tobacco and non-tobacco smokers, were observed. Tentatively, there’s a [reported](http://www.ccrmg.org/journal/05aut/nocancer.html) study in process of being published (as confirmed by a friend in email with lead author) which suggests no increased risk. > [@](#): > > there’s reason to believe that cannabis, unlike nicotine, may not be inherently carcinogenic Neither is [nicotine](http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=14570033&query_hl=14&itool=pubmed_docsum), for that matter. Cecil probably meant tobacco, but even that would be wrong since “inherently carcinogenic” implies an near-inevitability of cancer in all smokers rather than the small minority of [smokers](http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=15213107) who actually get it: > [@Tobacco-mortality study](#): > > By combining the penultimate columns of tables 5 and 6, we calculated the annual lung cancer mortality rates per 1000 continuing cigarette smokers at ages 45-54 through to 75-84 to be 0.6 (that is, 8.5×33/487), 1.8, 6.2 and 8.7 respectively. ---
**Author:** ![PetW](https://avatars.discourse-cdn.com/v4/letter/p/d2c977/32.png) [@PetW](https://boards.straightdope.com/u/PetW)\ **Post date:** [April 14, 2006, 6:48pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/2 "2006-04-14T18:48:12Z")
I agree with pretty much everything you’ve said except > [@II Gyan II](#): > > Cecil probably meant tobacco, but even that would be wrong since “inherently carcinogenic” implies an near-inevitability of cancer in all smokers rather than the small minority of [smokers](http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=15213107) who actually get it: I think “inherently carcinogenic” may be referring to the possibility that cannabis isn’t carcinogenic by itself, but only when smoked. ---
**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\ **Post date:** [April 14, 2006, 8:15pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/3 "2006-04-14T20:15:37Z")
> [@II Gyan II](#): > > Neither is [nicotine](http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=14570033&query_hl=14&itool=pubmed_docsum), for that matter. [This cite suggests something slightly different](http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=151834): > [@](#): > > Redundant Akt activation by nicotine and NNK could contribute to tobacco-related carcinogenesis by regulating two processes critical for tumorigenesis, cell growth and apoptosis. > … > Multiple lines of evidence support our hypothesis that nicotinic activation of Akt plays a role in lung tumorigenesis. > … > Nicotinic alteration of other cell types may also contribute to lung tumorigenesis. In addition to increasing epithelial cell survival as described in this report, nicotine can stimulate endothelial cell growth and angiogenesis (43). This is relevant because a lung cancer precursor lesion, angiogenic squamous dysplasia (44), was recently described that recapitulates the growth-promoting effects of nicotine on epithelial and endothelial cells in vivo. Whether the angiogenic properties of nicotine require Akt activation is unclear, but multiple angiogenic factors induced by nicotine, including VEGF and angiopoietin (45, 46), require activation of Akt for biologic activity. It seems to me that nicotine may indeed play a role in causing tumors. > [@Il Gyan](#): > > Cecil probably meant tobacco, but even that would be wrong since “inherently carcinogenic” implies an near-inevitability of cancer in all smokers rather than the small minority of [smokers](http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=15213107) who actually get it: Where do you get that “inherently carcinogenic” implies a near-inevitability of cancer in all smokers? All “carcinogenic” means is [capable of causing cancer](http://www.cdc.gov/niosh/2001-133o.html). Daniel ---
**Author:** ![II\_Gyan\_II](https://avatars.discourse-cdn.com/v4/letter/i/bbe5ce/32.png) [@II\_Gyan\_II](https://boards.straightdope.com/u/II_Gyan_II)\ **Post date:** [April 14, 2006, 8:42pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/4 "2006-04-14T20:42:16Z")
> [@Left Hand of Dorkness](#): > > It seems to me that nicotine may indeed play a role in causing tumors. It may, but Cecil is clearly attributing cig-smoking-caused cancers to nicotine, although that’s not where the blame falls. Even in the ‘Discussion’ section of your cite, it says: “_Although nicotine per se is not thought to be carcinogenic, the risks of long-term nicotine supplementation are unknown._”. > [@](#): > > Where do you get that “inherently carcinogenic” implies a near-inevitability of cancer in all smokers? Then “inherently carcinogenic” is an oxymoron. Inherently means ‘inseparably’. It doesn’t make sense to apply an absolutist adjective to a probabilistic category. I was treating carcinogenic as ‘causing cancer’, although the -ic should have warned me. ---
**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\ **Post date:** [April 14, 2006, 8:55pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/5 "2006-04-14T20:55:34Z")
> [@II Gyan II](#): > > It may, but Cecil is clearly attributing cig-smoking-caused cancers to nicotine, although that’s not where the blame falls. Even in the ‘Discussion’ section of your cite, it says: “_Although nicotine per se is not thought to be carcinogenic, the risks of long-term nicotine supplementation are unknown._”. It seems to me up i nthe air. I think you’re right, though, that “tobacco” would have been a better word there; it’d also be more analogous to “cannabis.” So I’l remove that quibble. > [@](#): > > Then “inherently carcinogenic” is an oxymoron. Inherently means ‘inseparably’. It doesn’t make sense to apply an absolutist adjective to a probabilistic category. I was treating carcinogenic as ‘causing cancer’, although the -ic should have warned me. Yes, “inherently” means “inseparably.” It doesn’t mean “inevitably” or “always.” If your quibble is right, then it’s **wrong** to say that nicotine is inherently carcinogenic, but it’s a useful distinction to make that it’s not. Nicotine doesn’t cause cancer itself, but it addicts people to habits that cause them to ingest carcinogens; one could say it’s indirectly carcinogenic, but not inherently carcinogenic. THC might not be inherently carcinogenic, by comparison, but IF it turns out that other components of marijuana are carcinogenic, then by encouraging folks to ingest these other components, THC could be called indirectly carcinogenic. Daniel ---
**Author:** ![II\_Gyan\_II](https://avatars.discourse-cdn.com/v4/letter/i/bbe5ce/32.png) [@II\_Gyan\_II](https://boards.straightdope.com/u/II_Gyan_II)\ **Post date:** [April 14, 2006, 9:20pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/6 "2006-04-14T21:20:50Z")
> [@Left Hand of Dorkness](#): > > Yes, “inherently” means “inseparably.” It doesn’t mean “inevitably” or “always.” For X to be inseparably ‘something’, it means it is always ‘something’; otherwise it’s separable. > [@](#): > > one could say it’s indirectly carcinogenic, but not inherently carcinogenic. The problem with this general discussion is that context matters and it is being lost. Given that people get cancer naturally i.e. in the absence of the input of any recognized risk factors, do we say that the human body is inherently carcinogenic? By the apparent standard, I’d guess Yes. Thing is, with tobacco or cannabis or any other “carcinogen”, not all who are exposed to them get cancer, yet we attribute the agency to the external agent, when actually it’s a synergistic event. Even among 70 year old continuing smokers, there are 6.2 lung cancer deaths p.a. among 1000 smokers, which is closely aligned with the incidence given the survival odds (60% dead within a year of getting the lung cancer), yet we don’t say that those 6 individuals had a vulnerable physiology, but that smoking killed them. The causality is shifted from the nexus to the external agent. In that light, I was objecting to labelling tobacco as ‘inherently carcinogenic’, given the lack of near-inevitability. Now if we shift the argument to prevalence i.e. among 10,000 cucumber-eaters, X get cancer, whereas among celery-eaters, only X/15 get cancer. And that X crosses some arbitrary threshold such that we think it’s reasonable to label cucumber as “inherently carcinogenic”, well, then that’s a subjective judgement. ---
**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\ **Post date:** [April 14, 2006, 9:36pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/7 "2006-04-14T21:36:57Z")
> [@II Gyan II](#): > > For X to be inseparably ‘something’, it means it is always ‘something’; otherwise it’s separable. Even if I accept your semantic argument–which I don’t–it’s still incorrect to say that it’s a mistake to call something “inherently carcinogenic.” Russian Roulette is an inherently risky game, even if we define “risky” as “capable of causing harm,” and even if only one chamber is loaded. This is an unexceptional combination of words. As for the rest of your post, it looks to me as if you’re arguing against tobacco being carcinogenic. Yeah, good luck with that. Daniel ---
**Author:** ![Khadaji](https://avatars.discourse-cdn.com/v4/letter/k/9e8a1a/32.png) [@Khadaji](https://boards.straightdope.com/u/Khadaji)\ **Post date:** [April 14, 2006, 10:09pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/8 "2006-04-14T22:09:25Z")
When I was diagnosed with Glaucoma I did a brief investigation and found that some studies are not embracing it as a treatment either: From [here](http://www.nei.nih.gov/news/statements/marij.asp) > [@](#): > > Studies in the early 1970s showed that marijuana, when smoked, lowered intraocular pressure (IOP) in people with normal pressure and those with glaucoma. In an effort to determine whether marijuana, or drugs derived from marijuana, might be effective as a glaucoma treatment, the National Eye Institute (NEI) supported research studies beginning in 1978. These studies demonstrated that some derivatives of marijuana transiently lowered IOP when administered orally, intravenously, or by smoking, but not when topically applied to the eye. > > However, none of these studies demonstrated that marijuana – or any of its components – could lower IOP as effectively as drugs already on the market. In addition, some potentially serious side effects were noted, including an increased heart rate and a decrease in blood pressure in studies using smoked marijuana. And [here](http://www.mfiles.org/Marijuana/medicinal_use/b3_glaucoma.html) > [@](#): > > The dose of marijuana necessary to produce a clinically relevant effect in the short term appears to produce an unacceptable level of undesirable side effects such as euphoria, systemic hypotension, and/or dry eye and conjunctival hyperemia in the majority of glaucoma patients in whom the drug has been carefully studied."National Institutes of Health Report, page 12 ---
**Author:** ![II\_Gyan\_II](https://avatars.discourse-cdn.com/v4/letter/i/bbe5ce/32.png) [@II\_Gyan\_II](https://boards.straightdope.com/u/II_Gyan_II)\ **Post date:** [April 14, 2006, 10:17pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/9 "2006-04-14T22:17:34Z")
> [@Left Hand of Dorkness](#): > > Russian Roulette is an inherently risky game, even if we define “risky” as “capable of causing harm,” and even if only one chamber is loaded. Everything is inherently risky. Either we use ‘inherently’ to mean A)non-zero risk B)some risk above a subjective threshold C)inevitable (or near) The first standard is useless; the second, a value judgement, and the third, IMHO, the only useful one. > [@](#): > > As for the rest of your post, it looks to me as if you’re arguing against tobacco being carcinogenic. I’m not. I argued that the human body is itself “inherently carcinogenic” if we use criteria A above. In that case, tobacco qualifies. If we use C, then it doesn’t. ---
**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\ **Post date:** [April 15, 2006, 6:37pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/10 "2006-04-15T18:37:04Z")
> [@II Gyan II](#): > > Everything is inherently risky. Either we use ‘inherently’ to mean > > A)non-zero risk > B)some risk above a subjective threshold > C)inevitable (or near) > > The first standard is useless; the second, a value judgement, and the third, IMHO, the only useful one. And yet nearly everyone uses B, yes? Or can you point to a variety of sources (especially relevant sources–e.g., discussions of health risks from peer-reviewed sources) that use A or C? Daniel ---
**Author:** ![II\_Gyan\_II](https://avatars.discourse-cdn.com/v4/letter/i/bbe5ce/32.png) [@II\_Gyan\_II](https://boards.straightdope.com/u/II_Gyan_II)\ **Post date:** [April 15, 2006, 7:09pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/11 "2006-04-15T19:09:30Z")
> [@Left Hand of Dorkness](#): > > And yet nearly everyone uses B, yes? Which makes the word ‘inherently’ useless, as far as communicating objective information goes. ---
**Author:** ![Moirai](https://avatars.discourse-cdn.com/v4/letter/m/96bed5/32.png) [@Moirai](https://boards.straightdope.com/u/Moirai)\ **Post date:** [April 15, 2006, 8:50pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/12 "2006-04-15T20:50:20Z")
My SIL, while doing post-doctoral work at USC, was part of an ongoing study of prepubescent (under 12, IIRC) marijuana use causing psychotic episodes. In a number of the kids , the psychosis was permanent- at least, they haven’t come out of it in the 5 years since… Rather disturbing study- don’t know if the lab has published yet but I will check. ---
**Author:** ![anaitys](https://avatars.discourse-cdn.com/v4/letter/a/34f0e0/32.png) [@anaitys](https://boards.straightdope.com/u/anaitys)\ **Post date:** [April 15, 2006, 11:53pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/13 "2006-04-15T23:53:56Z")
I’ve got a colleague who published the study showing a correlation between a certain genotype for a neuron receptor and adolescent marijuana increasing incidence of schizophrenia by age 26. What it boils down to, he says, is that if you’ve got a certain genetic propensity to it, smoking dope as an adolescence more than doubles your chance of becoming schizophrenic in adulthood. He also says there are not current plans to offer a quick mail-in genetic test for this, but maybe there ought to be :o) ---
**Author:** ![II\_Gyan\_II](https://avatars.discourse-cdn.com/v4/letter/i/bbe5ce/32.png) [@II\_Gyan\_II](https://boards.straightdope.com/u/II_Gyan_II)\ **Post date:** [April 16, 2006, 1:08am UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/14 "2006-04-16T01:08:34Z")
The study referenced by **anaitys** is Moderation of the effect of adolescent-onset cannabis use on adult psychosis by a functional polymorphism in the catechol-O-methyltransferase gene: longitudinal evidence of a gene X environment interaction. ([abstract](http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Abstract&list_uids=15866551), [PDF](http://www.ukcia.org/research/COMTgene.pdf) of full paper) ---
**Author:** ![DSYoungEsq](https://avatars.discourse-cdn.com/v4/letter/d/c6cbf5/32.png) [@DSYoungEsq](https://boards.straightdope.com/u/DSYoungEsq)\ **Post date:** [April 17, 2006, 2:02pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/15 "2006-04-17T14:02:02Z")
> [@II Gyan II](#): > > Everything is inherently risky. Either we use ‘inherently’ to mean > > A)non-zero risk > B)some risk above a subjective threshold > C)inevitable (or near) > > The first standard is useless; the second, a value judgement, and the third, IMHO, the only useful one. I have an interesting thought. How about we use the word “inherent” as it is actually defined: " involved in the constitution or essential character of something : belonging by nature or habit " Russian Roulette is “inherently” risky because risk is an essential character of the game. You “risk” death each time you pull the trigger, even though death is not an inevitable outcome. It would be, by contrast, incorrect to call it an “inherently deadly” game, unless the rules forced trigger pulling to the point of someone being shot, or unless you define “deadly” to mean “having a chance of death.” For something to be “inherently carcinogenic,” all that is needed is that the factor of carcinogenicy (the ability to cause cancer) is an essential character of the substance. That is, is it the substance itself that creates the possibility of cancer, as opposed to the substance only being involved in cancer when combined with other factors. Which is not to say I have an opinion on the application of that term to either nicotine or any other substance under discussion. It just helps to argue semantics using actual definitions, not made up concepts… ---
**Author:** ![II\_Gyan\_II](https://avatars.discourse-cdn.com/v4/letter/i/bbe5ce/32.png) [@II\_Gyan\_II](https://boards.straightdope.com/u/II_Gyan_II)\ **Post date:** [April 17, 2006, 2:35pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/16 "2006-04-17T14:35:31Z")
> [@DSYoungEsq](#): > > I have an interesting thought. How about we use the word “inherent” as it is actually defined: > … > It just helps to argue semantics using actual definitions, not made up concepts… “Actually defined” by whom? English is not like French, with some national academy dictating the rules. I already provided the definition of ‘inherently’ above, as ‘inseparably’, from Google definitions. > [@](#): > > That is, is it the substance itself that creates the possibility of cancer, as opposed to the substance only being involved in cancer when combined with other factors. This can never be shown, as you would have to examine every cigarette smoker’s complex bodily constitution thoroughly to detect commonality of features among those who got cancer and possible differences from those who didn’t. ---
**Author:** ![CJJ](https://avatars.discourse-cdn.com/v4/letter/c/ecc23a/32.png) [@CJJ](https://boards.straightdope.com/u/CJJ)\ **Post date:** [April 17, 2006, 4:18pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/17 "2006-04-17T16:18:25Z")
> [@II Gyan II](#): > > “Actually defined” by whom? English is not like French, with some national academy dictating the rules. > > I already provided the definition of ‘inherently’ above, as ‘inseparably’, from Google definitions. [Merriam-Webster definition for “inherently”](http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=inherently) - involved in the constitution or essential character of something : belonging by nature or habit I think this is a rather standard definition; it’s not much of a leap to say “belongs by nature” = “inseparable”, though I’m personally having trouble finding a definition on-line that “inseparable” as a synonym for “inherent”. It should be clear by now that calling cannabis “inherently carcinogenic” means that the substance itself possesses cancer-causing qualities, rather than, e.g., the method by which it is ingested. Anticipating your objection: > [@II Gyan II](#): > > This can never be shown, as you would have to examine every cigarette smoker’s complex bodily constitution thoroughly to detect commonality of features among those who got cancer and possible differences from those who didn’t. Then I think it’s the word “carcinogenic” that you have a problem with. By the definition you propose, nothing could be carcinogenic unless it produced cancer in every single case. This, to me, seems like an overly-fastidious requirement, as is the earlier quibble that words must convey only clear, objective information to be useful. If I were you, I’d concede the point and move on; it’s distracting you from the far more important ideas raised in your original post. ---
**Author:** ![II\_Gyan\_II](https://avatars.discourse-cdn.com/v4/letter/i/bbe5ce/32.png) [@II\_Gyan\_II](https://boards.straightdope.com/u/II_Gyan_II)\ **Post date:** [April 17, 2006, 4:52pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/18 "2006-04-17T16:52:05Z")
> [@CJJ\*](#): > > It should be clear by now that calling cannabis “inherently carcinogenic” means that the substance itself possesses cancer-causing qualities, rather than, e.g., the method by which it is ingested. The point I’m making is saying that ‘something’ is “inherently carcinogenic” indicates that the presence of something is the controlling variable. As shown in the tobacco study cited above, dosage matters. Even among those who have ingested similar gross dosage, a small minority of smokers get lung cancer. There are many other variables involved. From that perspective, it makes little sense to label tobacco “inherently” carcinogenic. ---
**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\ **Post date:** [April 17, 2006, 6:15pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/19 "2006-04-17T18:15:58Z")
> [@II Gyan II](#): > > The point I’m making is saying that ‘something’ is “inherently carcinogenic” indicates that the presence of something is the controlling variable. By “controlling variable,” do you simply mean that, all other factors being equal, the presence of this substance creates an increased risk of cancer? If so, you’re correct, and tobacco is inherently carcinogenic. The fact that a small minority of smokers get cancer is not the point: the point is that they get lung cancer in hugely disproportionate numbers when compared to nonsmokers. Consider “carcinogenic” to mean “a ticket for the cancer lotto.” Not everyone who buys a ticket wins the lottery, but if you don’t buy a ticket, you’re not going to win. (Note, of course, that tobacco is only one of many carcinogens). The fact that only humans are eligible to win the lottery, or that only a small minority of lottery-ticket-holders win, in no way invalidates this idea. All other factors will never be equal, of course; that’s why we have epidemiological studies, to smooth out those other factors. It appears to me that you’re trying to postmodernify the word “carcinogenic,” to analyze it into meaninglessness. I’m not sure what the purpose of such an effort would be. Daniel ---
**Author:** ![II\_Gyan\_II](https://avatars.discourse-cdn.com/v4/letter/i/bbe5ce/32.png) [@II\_Gyan\_II](https://boards.straightdope.com/u/II_Gyan_II)\ **Post date:** [April 17, 2006, 7:12pm UTC](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658/20 "2006-04-17T19:12:19Z")
> [@Left Hand of Dorkness](#): > > The fact that a small minority of smokers get cancer is not the point: the point is that they get lung cancer in hugely disproportionate numbers when compared to nonsmokers. Except that dosage matters; so does [method](http://cebp.aacrjournals.org/cgi/content/abstract/13/12/2035) of administration. The mere presence is not risky. Dosage, frequency & method are the salient variables. Saying that tobacco is “inherently” carcinogenic gives the impression that you are at risk of cancer irrespective of how modulate the tobacco use, but the increased risk doesn’t show up in epidemiological studies until you cross a certain dosage threshold. [Next page](https://boards.straightdope.com/t/not-even-the-straight-dope-on-dope-still-smokin-14apr2006/352658.md?page=2)