Study finds cannabis least dangerous of illicit recreational drugs

A pair of researchers affiliated with several institutions in Germany, has found that of a number of drugs used by people for recreational purposes (i.e. for non-medicinal reasons and without a prescription) cannabis is the least dangerous—at least when measuring the lethality of a single dose. In their paper published in Scientific Reports, Dirk Lachenmeier and Jürgen Rehm describe their study of the lethality of several illicit drugs and their results.

In most circles, cannabis, aka marijuana, weed, etc., is considered far less harmful to the body than other drugs such as cocaine, heroin or even alcohol—at least in direct short term ways. In this new study, the researchers set out to learn if that is indeed the case. They subjected test animals to high doses of several drugs to learn their lethality levels, then compared what they found with the average use levels of real people who use the drugs recreationally—this allowed them to derive a ratio number they call a Margin of Exposure (MOE)—a measurement tool that indicates the lethality of a drug based on how much of it is usually taken. It does not take much cocaine, for example, to kill a person, but most people take far less than that limit and thus survive to try it again, and again, if they so desire. To show where cannabis stands with other popular recreational drugs, the researchers created a chart showing the MOE of various drugs, which showed that cannabis sat at the very bottom, by far the safest of the bunch, which included from most deadly to least: alcohol, heroin, cocaine, tobacco, ecstasy and meth.

It is doubtful that anyone will be surprised that cannabis is at the bottom of the list, much more surprising is that alcohol is at the top, more deadly than any of the other recreational drugs—a statistic the researchers note that is ironic when considering that selling, buying and consuming alcohol is legal whereas doing the same with cannabis is not in most places.

Of course, the research does not take into account the other impacts of the drugs on the list, such as deaths related to drug crimes, car crashes or suicide (or even side effects such lung disease or stroke) or the harm that can be caused by job loss, inattention to child care, or the toll they can take on relationships.

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