Foolish Ingestion?

Social and Physical Risks of Marijuana

Posted May 19, 2014


 I am not an authority, personally or professionally, on drug use but I have become something of an expert on foolish action, which I define as behavior that ignores risk. Living just outside Denver--Ground Zero for the recreational marijuana legalization movement in the US--has caused me to become interested in marijuana use, particularly as it relates to the topic of risk-ignoring. This is a tricky topic for me, as I do not want to appear to be an opponent of legalization: someone who is offering exaggerated warnings against the dangers of pot-use, as in the 1936 cautionary propaganda film “reefer madness.”

 In fact, like most liberals (of both the libertarian and political stripe), I consider marijuana to be benign for most users, and with many medical and other benefits; I think that its legalization is a generally good idea, for various reasons, including freedom (people should be left alone to make decisions, good or bad, that affect mainly themselves), politics (legalization is something that voters increasingly want), economics (marijuana can be a huge source of new tax revenues), crime policy (the war on drugs does not prevent drug use and has catastrophically and unfairly filled our prisons), and public health (unregulated illegal drugs are undoubtedly more dangerous than regulated legal ones).

 But any public policy or individual action comes with both rewards and risks, and when societies or persons get in trouble it is usually because avoidable risks were ignored. And making it possible for any adult to walk into a store and casually purchase marijuana in various forms does entail some risks, as was the case with the legalization (after an analogous, but shorter, period of Prohibition) of another mood-altering substance: alcohol. Risks come in two forms: social and physical. I shall discuss several sub-categories of risk within each of those two broad categories, and then focus on the one area of marijuana use--ingestibles (cannabis-laced cookies and candies)--where the risks are greater than perhaps had been realized.

                         Social Risks of Cannabis Legalization and Use

 There are five forms of social risk associated with present-day marijuana use. One of them (infiltration by criminal elements), impacts society, while four of them (legal difficulty, job termination, addiction, loss of motivation) impact individuals. Of these four, the first two (legal difficulty, job termination) are problematic mainly due to external rules and realities which a foolish user (more due to stupidity than to drug effects) ignores at his or her peril.

 Infiltration by Criminal Elements

 Just as illegal gambling and drug distribution has been a specialty of criminal cartels and gangs, legalization of these activities likely will continue to appeal to these elements. That was certainly true in Nevada with the involvement of the Mafia in legalized gambling, and there are some signs that the same thing is happening in the legalized marijuana industry, as seen in involvement of Russian mobsters in Dutch “coffee shops” and recent closures of two nascent pot businesses in Denver (the real “New Amsterdam”?) because of apparent money-laundering infiltration by Mexican drug criminals. These are manageable risks, however, and give something for police forces to investigate (and to use new tax sources for), as their attention is diverted from pursuing low-level drug users and distributors.

 Legal Difficulty faced by Marijuana Users

 At one time possession of even small amounts of marijuana could expose one to a lengthy jail sentence, but today possession for personal use only has been decriminalized in most places. Smoking dope in public continues to be frowned on, however, even in Colorado (which legalizes sales, but does not authorize using in the place where it is sold or elsewhere, such as in private clubs). That prohibition is starting to erode, however, and enforcement is difficult to carry out, especially in mass events such as a planned open-air concert series (which the state is trying to shut down) by the Colorado Symphony Orchestra in which attendees are encouraged to bring their own grass to smoke while listening to the (presumably drug-themed) music.

 The main legal risk to marijuana users in a legalized state such as Colorado (other than the increasing likelihood of being arrested for driving while stoned), comes when purchasers come in contact with a legal jurisdiction or authority outside of or above Colorado. An example driving across state lines (allegedly, Wyoming cops are targeting state residents with a just-purchased stash driving northward from Denver). In theory, non-state residents cannot purchase, but I know from my one store visit (for research purposes, of course) that IDs are not checked except for age, when making these (because of bank shunning of pot business) cash-only purchases. Most users are well-aware of such risks, however, and know of the need to exercise care when dealing with the less marijuana-tolerant world outside of Colorado. Naïve, stubborn or highly addicted individuals sometimes fail to heed these rules, as in the case of a college student I know who got in trouble after he repeatedly ignored his college’s warning not to toke in public places on campus.

Threat of Job Loss

 The biggest social cost of legal marijuana use comes from the fact that many habitual users, especially those in relatively low-paying jobs, work in settings where a positive result on a drug test, often randomly administered, is a bar to obtaining or retaining a job. Acquiring a reputation as a marijuana user can follow a person and create problems years later. Because residues of marijuana stay in the body for days, it is difficult for daily users to beat drug tests, even when they know they are coming. This can have serious financial consequences for a busted person, as seen in the many stories of professional football and basketball players—for whom marijuana does not enhance performance, but undoubtedly helps to deal with the constant physical grind—who get suspended from their high-paying jobs.

 Risk of Addiction

 Although marijuana does not have nearly the addictive power of other drugs, such as say heroin and cocaine (or even alcohol), it is a myth to claim that it is never addictive. About ten percent of marijuana users can be said to be addicted both for psychological and physical reasons (ceasing use can cause physical and emotional discomfort for a heavy user). One sign of marijuana addiction is the development of a tolerance, which causes the person to greatly increase the amount and frequency of use. (This dose-increasing mechanism in fact is also seen in heroin addicts, and is one of the explanations [others being the increased potency of the product, and the ever-present possibility of allergic reactions to unknown adulterants] for the many high-profile deaths occurring over the years to celebrity heroin injectors, such as most recently, Phillip Seymour Hoffman). Unlike other drugs, overusing or overdosing on marijuana will almost certainly not kill you (this topic is addressed below), but it can have other undesirable effects.

 Loss of Motivation

 The most-noted deleterious consequence of heavy marijuana use is a loss of motivation in academic and work pursuits, as in such things as no longer taking school assignments, career ambitions or other strivings seriously. In Timothy Leary’s famous 1966 counter-culture quote “turn on, tune in, drop out,” this effect of hallucinogenic drug use was portrayed as a good thing. More recently, California Governor Jerry Brown (who in his late 1970’s incarnation as “Governor Moonbeam” likely took an occasional puff, although he refuses to talk about it), has recently come out against legalization of marijuana, pointing to research suggesting heavy pot use can bring about brain changes and related cognitive deficits. Mainly, however, he used a motivational argument, saying in a TV interview “How many people can get stoned and still have a great state or a great nation? The world’s pretty dangerous, very competitive. I think we need to stay alert, if not 24 hours a day, more than some of the potheads might be able to put together.”

 This position, arguing that legalized marijuana will jeopardize American economic competitiveness, has been widely ridiculed, probably for good reason. Nevertheless, Brown has a point when he argues that wider availability of marijuana will likely cause some people to jump off the Protestant Ethic bandwagon. But his argument rests on three questionable assumptions: (a) that these people could not have gotten grass illegally (which of course they could); (b) that the fate which befalls some individuals will affect most individuals (which of course it will not); and (c) that the causal connection works in only one direction (when in fact the marijuana use may be a result, rather than the cause, of weak achievement motivation). Furthermore, the same “nanny state” arguments about deleterious societal consequences were used in the 1920’s to try and prevent resuming legal sale of alcohol (which has messed up many more lives than marijuana) and were ultimately rejected as overly paternalistic.

The main concern I have on the motivational front has to do with adolescents and pre-adolescents, who in spite of age restrictions on pot purchases, will likely have easier access to grass once it is legalized. Kids who are stoners are generally mess-ups in school and elsewhere, but their access to drugs (and alcohol, which is probably a bigger problem for them) is already substantial, and their use is affected more by negative peer influences than accessibility. The teens most likely to be affected by legalization are the straight-arrow high achievers, along the lines of Bill Gates (who used LSD, and probably weed, when young, and who—along with other software moguls--has refused to impose drug-testing at his company) who Jerry Brown seems most concerned about. Here the impact may be less from availability of the drug, or from peer influences, as from the implicit “pot is okay” message they are getting when they see their middle-aged parents start to light up.

                            Physical Risk of Cannabis Legalization and Use

 Proponents of marijuana legalization argue that, in contrast to other substances, marijuana is a perfectly safe drug to imbibe. This is undoubtedly an exaggeration, given that any consumed chemical substance, no matter how generally safe, can be unsafe for some people. In this section, I discuss briefly five possible physical side effects: lung damage, unsafe driving, brain changes, cardiac responses and psychotic reactions.

 Effects on Lung Function

 Because ceremonial cannabis use is central to the Rastafari religion practiced by many Jamaican reggae musicians, and as the most famous such musician, Bob Marley, died allegedly of lung cancer at age 36, I assumed there would be some evidence that smoking weed causes lung disease, including emphysema and lung cancer. In fact, Marley died of melanoma, which had spread to various organs including his lungs. Furthermore, Marley was also a heavy smoker of tobacco, something that is true of many marijuana smokers, so the effects are somewhat confounded. Although marijuana smoke contains many of the same carcinogenic particles found in tobacco smoke, there is no evidence that by itself it causes serious lung disease. The likely explanation is that moderate marijuana users smoke at most one or two joints a day, while moderate tobacco users smoke a pack (twenty cigarettes) or more a day. Nevertheless, very heavy and long-term marijuana use undoubtedly causes some lung irritation, and related symptoms such as coughing and mucus accumulation. Marijuana inhalation is probably not good for one’s lungs, but there is no evidence at this point that it causes serious lung disease. However, with much more widespread marijuana use, a different picture may begin to emerge.

 Effects on Driving Competence

 There is a general belief among legalization advocates that cannabis does not cause driving to become significantly impaired. In fact, this is one belief that happens to be true. Many studies have found that while psychomotor functioning and reaction time are mildly affected by cannabis, crash culpability remains normal. The most likely explanation is that people who are high on marijuana are very aware of that fact, and drive more cautiously, by slowing down, narrowing their focus and becoming more alert for danger. In contract, people who have consumed alcohol become less concerned about danger and drive more recklessly. This will not stop police authorities from trying to develop new test protocols for identifying and arresting stoned drivers, in the mistaken belief that cannabis-affected drivers pose a major public menace. At least based on current knowledge, that does not appear to be the case.

 Possible Cognitive Diminution

 As marijuana affects brain functioning, one should ask about the nature and permanency of brain effects. There is no discernible evidence of structural changes in the brains of marijuana users. There is some evidence of short-term effects on memory, learning and executive functioning (planning and reasoning), although the effects are mild and temporary. There is some evidence that for chronic long-term users, cognitive capacities are somewhat diminished, although the studies are poorly controlled and results are confounded (people with lower cognitive capacity may be more attracted to habitual use). Paradoxically, in one of the few well-controlled studies, chronic users were not affected in their ability to perform complex cognitive tasks after using cannabis, perhaps because of their greater tolerance (in the same way that alcoholics are often little affected cognitively by alcohol, until of course they become sloppy drunk). In sum, while cognitive functioning is likely affected short term by marijuana use, this is probably not as big as problem as some alarmists (such as California Governor Jerry Brown) allege.

 Cardiac Responses

 It is known that marijuana use brings about an elevation in one’s heart rate. However, the general belief among medical experts has been that death cannot occur from an overdose of marijuana, even in individuals with underlying heart disease. There is one exception to the assertion that marijuana cannot cause death, and that is when marijuana is consumed in combination with some other substance. A careful study in Germany, however, claims to have found evidence that marijuana was the sole cause of death in two cases. Nevertheless, death from a physiological response to acute cannabis intoxication is so remote a possibility as to not be worthy of concern. Death resulting from marijuana-induced psychotic behavior is a different story, however.

 Psychotic Reactions

 My only experience with marijuana was back in the 1970’s when a poor quality joint would be passed among a group of party-goers and everyone would take a drag. Whether due to low potency, insufficient number of puffs from sharing, or my own Bill Clintonesque inexperience with inhaling, the stuff never had any effect on me (other than from exposure to germs) and I wondered why marijuana was considered a hallucinogen. Then one day I found out.

 At a party around 1978 in California, several joints made from high quality weed were passed out and I had a reefer all to myself. Determined to finally get high, I inhaled furiously, and when I started to feel the effects, I kept on going for a minute or two longer. Then I began to have hallucinations, mostly of an auditory nature along with depersonalization (a kind of out of body experience) and paranoid delusions. The whole experience was very negative and scary. This bad trip (technically, a cannabis-induced psychotic state) lasted for a couple of hours, and I seriously thought I was permanently losing my mind. Fortunately, the other people at the party were experienced users who had mostly all had at least one bad trip, and they were very supportive and calmly reassuring in talking me down. That was over 35 years ago and except for one celebratory puff recently, I have never tried marijuana again.

 One or more bad trips are reported in the experiences of a significant percentage of regular cannabis users. These are transient, and almost never do they result in permanent harm to the individual, except perhaps if there is an underlying predisposition to serious mental illness. The real danger of bad trips is when the person (often a first-timer who does not understand what is happening) does something rash, such as harming themselves or others. While very rare, that appears to be one of the risks of cannabis use, as two recent Denver stories illustrate. Both of them involved inexperienced users who had consumed a large quantity of marijuana in edible form purchased at one of the newly legalized marijuana outlets. In one case, a college student jumped out a hotel room window to his death, after consuming some cookies. In the other case, a man in his thirties killed his wife (who was in the process of calling 911 when he threatened to shoot himself) after consuming some gummy bears. As both of these events happened after ingestion of cannabis-laced edibles (something that has not happened, at least in Colorado, after smoking), I believe (also based on other evidence) that a case can be made for banning (or at least, much more strictly regulating), the commercial manufacture and distribution of marijuana-laced cookies, candies and beverages.

                                       The Problem Is Edibles

 There are three problems with edibles. The first one is that the doses are unknown, they vary considerably, and in many cases are reported to be extremely high. Clearly, it is improper to be selling any product for human consumption where the consumer has no idea of the nature or strength of what he or she is consuming. The second problem with edibles is that it takes much longer for the drug to take effect and the effects take much longer to go away. In a naïve user (as in the two recent Denver tragedies), when nothing happens for a while, the natural tendency is to keep taking more. Then when the drug effect does kick in, the result is acute intoxication and related problems. This is less likely to happen with inhaled marijuana, because the dose is lower, the effects are much more immediate and the user can more easily self-regulate the amount that is consumed. The third problem with commercially distributed edibles is that they look just like store-bought cookies and candies (even the packaging can give that impression) and thus have a high likelihood of being accidentally ingested by young children. (What little kid can resist eating a gummy bear?). The director of emergency medicine at the University of Colorado Medical School has reported a many-fold increase post-legalization in children admitted to the hospital after accidental poisoning from marijuana-laced edibles.

 With respect to weed sold in dried plant form, my feeling is that the risks, while not insubstantial, are acceptable. Any competent adult should be able to freely take on those risks, hopefully after calculating what those risks are. (Such knowledge-based calculation of risk, of course, usually is not performed). Edibles are a different story, however. Requiring people to bake their own marijuana-laced brownies seems a small inconvenience to impose in return for the greater public safety that would come from banning the sale of such a potentially dangerous product.


Two days after this column was first posted, the Governor of Colorado signed into law legislation that would require edibles to come in individual packages with clear indications that they contain drugs and in standard strenghts yet to be determined. The bill was signed at Colorado Children's Hospital, where many poisoned children have been treated. This is a good first step, and one that recognizes (at least for children) the public safety hazards posed by marijuana edibles.                    

                   Copyright Stephen Greenspan