A new study has found that vaping-related illnesses in 2019 occurred much more frequently in states where adult-use marijuana is illegal compared with those states that have ended cannabis prohibition.

The study, published in the Journal of the American Medical Association (JAMA) Network Open, reports that cases of e-cigarette/vaping-related lung injury (EVALI) affected 1.7 per million of the population in states where adult-use marijuana is legal, compared to 8.8 per million where it is only legal for medical purposes and 8.1 per million where it is completely illegal.

“It appears states that have legal access to marijuana have lower rates of EVALI cases, which is consistent with the hypothesis that people have demand for marijuana products, and in states where they don’t have access to them in this regulatory fashion, they end up purchasing them elsewhere,” said Alex Hollingsworth, one of the researchers from Indiana University in Bloomington.

The study’s authors believe their findings indicate that access to adult-use marijuana may lower incidences of EVALI, as similar research carried out by Leafly concluded late last year.

“One possible inference from our results is that the presence of legal markets for marijuana has helped mitigate or may be protective against EVALI,” they wrote on JAMA Open Network.

“The reason for this association is not yet clear. It is possible that in recreational states, people tend to purchase marijuana products at legal dispensaries, which may be less likely to sell the contaminated products that are thought to cause EVALI,” they added.

The researchers used data from the US Centers for Disease Control and Prevention (CDCP) which reports that 70 people died and nearly 3,000 were hospitalized last year due to EVALI, with the peak of the health crisis occurring in September. The CDCP later announced that vitamin E acetate is the most likely cause for the illness. Vitamin E acetate is a diluting agent most often used in counterfeit vape pens bought on the illicit market. The researchers also looked at CDCP data from 2017 indicating the prevalence of e-cigarette use between states.

While the JAMA study was very straightforward, the huge difference in EVALI incidences between legal and illegal states gives cause for further research and reflection on the harms caused by prohibition policies which create the conditions for an unregulated, illicit market.

“These findings come as little surprise. In jurisdictions where cannabis is legally regulated, consumers gravitate toward the above-ground retail marketplace where they can access lab-tested products manufactured by licensed businesses,” said Erik Altieri, NORML Executive Director.

“Just like alcohol prohibition gave rise to the illicit production of dangerous ‘bathtub gin,’ marijuana prohibition provides bad actors, not licensed businesses, the opportunity to fulfill consumers’ demand – sometimes with tragic results,” he added.

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