Marijuana

Is Marijuana a Dangerous Drug?
Any discussion of marijuana should begin with the fact that there have been numerous official reports and studies, every one of which has concluded that marijuana poses no great risk to society and should not be criminalized. These include: the National Academy of Sciences' "Analysis of Marijuana Policy"(1982); the National Commission on Marihuana and Drug Abuse (the Shafer Report) (1973); the Canadian Government's Commission of Inquiry (Le Dain Report) (1970); the British Advisory Committee on Drug Dependency (Wooton Report) (1968); the La Guardia Report (1944); the Panama Canal Zone Military Investigations (1916-29); and Britain's monumental Indian Hemp Drugs Commission (1893-4).

It is sometimes claimed that there is "new evidence" showing marijuana is more harmful than was thought in the sixties. In fact, the most recent studies have tended to confirm marijuana's safety, refuting claims that it causes birth defects, brain damage, reduced testosterone, or increased drug abuse problems.
The current consensus is well stated in the 20th annual report of the California Research Advisory Panel (1990), which recommended that personal use and cultivation of marijuana be legalized: "An objective consideration of marijuana shows that it is responsible for less damage to society and the individual than are alcohol and cigarettes."

Is Marijuana Harmful?
Just as most experts agree that occasional or moderate use of marijuana is innocuous, they also agree that excessive use can be harmful. Research shows that the two major risks of excessive marijuana use are: respiratory disease due to smoking and accidental injuries due to impairment.

Marijuana and Smoking:
A recent survey by the Kaiser Permanente Center found that daily marijuana-only smokers have a 19% higher rate of respiratory complaints than non-smokers. These findings were not surprising, since it has long been known that, aside from its psychoactive ingredients, marijuana smoke contains virtually the same toxic gases and carcinogenic tars as tobacco. Human studies have found that marijuana smokers suffer similar kinds of respiratory damage as tobacco smokers, putting them at greater risk of bronchitis, sore throat, respiratory inflammation and infections.

Although there has not been enough epidemiological work to settle the matter definitively, it is widely suspected that marijuana smoking causes cancer. Studies have found apparently pre-cancerous cell changes in marijuana smokers. Some cancer specialists have reported a higher-than-expected incidence of throat, neck and tongue cancer in younger, marijuana-only smokers. Some cases have been fatal. While it has not been conclusively proven that marijuana smoking causes lung cancer, the evidence is highly suggestive. According to Dr. Donald Tashkin of UCLA, the leading expert on marijuana smoking:

    "Although more information is certainly needed, sufficient data have already been accumulated concerning the health effects of marijuana to warrant counseling by physicians against the smoking of marijuana as an important hazard to health."

Fortunately, the hazards of marijuana smoking can be reduced by various strategies:

   1. Use of higher-potency cannabis, which can be smoked in smaller quantities
   2. Use of waterpipes and other smoke reduction technologies, and ingesting marijuana orally instead of smoking it

Is it True that One Joint Equals One Pack of Cigarettes?
Some critics exaggerate the dangers of marijuana smoking by fallaciously citing a study by Dr. Tashkin which found that daily marijuana smokers experienced a "mild but significant" increase in airflow resistance in the large airways greater than that seen in persons smoking 16 cigarettes per day. What they ignore is that the same study examined other, more important aspects of lung health, in which marijuana smokers did much better than tobacco smokers. Dr. Tashkin himself disavows the notion that one joint equals 16 cigarettes.

A more widely accepted estimate is that marijuana smokers consume four times as much carcinogenic tar as cigarettes smokers per weight smoked. This does not necessarily mean that one joint equals four cigarettes, since joints usually weigh less. In fact, the average joint has been estimated to contain 0.4 grams of marijuana, a bit less than one-half the weight of a cigarette, making one joint equal to two cigarettes (actually, joint sizes range from cigar-sized spliffs smoked by Rastas, to very fine sinsemilla joints weighing as little as 0.2 grams). It should be noted that there is no exact equivalency between tobacco and marijuana smoking, because they affect different parts of the respiratory tract differently: whereas tobacco tends to penetrate to the smaller, peripheral passageways of the lungs, marijuana tends to concentrate on the larger, central passageways. One consequence of this is that marijuana, unlike tobacco, does not appear to cause emphysema.

Does Prohibition Reduce the Harmfulness of Marijuana Smoking?
Whatever the risks of marijuana smoking, the current laws make matters worse in several respects:

   1. Paraphernalia laws have impeded the development and marketing of water pipes and other, more advanced technology that could significantly reduce the harmfulness of marijuana smoke.
   2. Prohibition encourages the sale of marijuana that has been contaminated or adulterated by insecticides, Paraquat, etc., or mixed with other drugs such as PCP, crack and heroin.
   3. By raising the price of marijuana, prohibition makes it uneconomical to consume marijuana orally, the best way to avoid smoke exposure altogether; this is because eating typically requires two or three times as much marijuana as smoking.

Has Anyone Ever Died from Using Marijuana?
The Kaiser study also found that daily marijuana users have a 30% higher risk of injuries, presumably from accidents. These figures are significant, though not as high as comparable risks for heavy drinkers or tobacco addicts. That marijuana can cause accidents is scarcely surprising, since marijuana has been shown to degrade short-term memory, concentration, judgment, and coordination at complex tasks including driving. There have been numerous reports of marijuana-related accidents - some of them fatal, belying the attractive myth that no one has ever died from marijuana. One survey of 1023 emergency room trauma patients in Baltimore found that fully 34.7% were under the influence of marijuana, more even than alcohol (33.5%); half of these (16.5%) used both marijuana and alcohol in combination. This is perhaps the most troublesome research ever reported about marijuana; as we shall see, other accident studies have generally found marijuana to be less dangerous than alcohol.

Nonetheless, it is important to be informed on all sides of the issue. Marijuana smokers should be aware that accidents are the number one hazard of moderate marijuana use. In addition, of course, the psychoactive effects of cannabis can have many other adverse effects on performance, school work, and productivity.
Is Marijuana a Major Road Safety Hazard?
A growing body of research indicates that marijuana is on balance less of a road hazard than alcohol. Various surveys have found that half or more of fatal drivers have alcohol in their blood, as opposed to 7 - 20% with THC, the major psychoactive component of marijuana (a condition usually indicative of having smoked within the past 2-4 hours). The same studies show that some 70% - 90% of those who are THC-positive also have alcohol in their blood. It therefore appears that marijuana by itself is a minor road safety hazard, though the combination of marijuana and alcohol is not. Some research has even suggested that low doses of marijuana may sometimes improve driving performance, though this is probably not true in most cases.

Two major new studies by the National Highway Transportation Safety Administration have confirmed marijuana's relative safety compared with alcohol. The first, the most comprehensive drug accident study to date, surveyed blood samples from 1882 drivers killed in car, truck and motorcycle accidents in seven states during 1990-91. Alcohol was found in 51.5% of specimens, as against 17.8% for all other drugs combined. Marijuana, the second most common drug, appeared in just 6.7%. Two-thirds of the marijuana-using drivers also had alcohol. The report concluded that alcohol was by far the "dominant" drug-related problem in accidents. It went on to analyze the responsibility of drivers for the accidents they were involved in. It found that drivers who used alcohol were especially culpable in fatal accidents, and even more so when they combined it with marijuana or other drugs. However, those who used marijuana alone appeared to be if anything less culpable than non-drug users (though the data were insufficient to be statistically conclusive). The report concluded, "There was no indication that marijuana by itself was a cause of fatal accidents." (It must be emphasized that this is not the case when marijuana is combined with alcohol or other drugs).

Illicit Drug Information - Marijuana

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