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No toxic basis to criminalize marijuana

BACK IN 1966, concerned that so many young people were harming themselves through the use of marijuana, I began to review the medical and scientific literature to help clarify the nature of this harmfulness. Much to my surprise, I discovered that it was a substance remarkably free of toxicity. In fact, it is far safer than any pharmaceutical or recreational drug. There is no record of a single overdose death around the world from its recreational or medicinal use. Compare that to aspirin, which is responsible for more than 1,000 deaths per year in this country alone.

Many of those who staunchly defend the prohibition against marijuana believe we do not yet know enough about it to be able to make the kinds of decisions that are now necessary. Despite the US government’s three-quarter-century-long prohibition of marijuana and its confinement to Schedule 1 of the Drug Control and Abuse Act of 1970, it is nonetheless one of the most studied therapeutically active substances in history; to date there are more than 20,000 published studies or reviews in the scientific literature referencing the cannabis plant and its cannabinoids, nearly half of which were published within the past five years.


By contrast hydrocodone, a pharmaceutical opioid which is responsible for a large and growing number of overdose deaths from illicit use, yields just more than 600 references in the entire compilation of the available scientific research. The entirety of this research supports none of the claims made by Governor Charlie Baker and his colleagues in their op-ed in the Boston Globe (“Do not legalize marijuana in Massachusetts,” March 7).

Lester Grinspoon
The writer is Associate Professor Emeritus of Psychiatry, Harvard Medical School.