New federally funded research has identified another public health protection in states that have legalized marijuana. Just before the COVID-19 pandemic, an outbreak of a mysterious respiratory disease emerged among some users of cannabis concentrates and e-cigarettes. The illness was eventually linked to an additive found most commonly in unregulated marijuana vape cartridges and hospitalized nearly 3,000 people in the U.S. and killed 68, according to the Centers for Disease Control and Prevention (CDC).
A recent study of the outbreak analyzed the relationship between state cannabis policies and the prevalence of the illness, known as EVALI (e-cigarette and vaping-associated lung injury). It found in states where cannabis was legal for adults, or where medical marijuana patients could legally grow their own cannabis, EVALI was significantly less prevalent.
Specifically, states with adult-use marijuana laws in place during the 2019 outbreak had a 42% lower incidence of EVALI cases, according to the study. And while state medical marijuana laws themselves seemed to have no significant association with prevalence of the disease, medical marijuana states that allowed home cultivation had a 60% lower EVALI incidence compared to those forbidding it.
“Recreational marijuana laws were associated with reduced EVALI incidence, whereas the relationship’s direction for medical marijuana laws depended on their policy attributes,” reads the report, authored by Yale School of Public Health professor Abigail Friedman and Meghan Morean, a psychiatry research scientist at the Yale School of Medicine.
“States in the highest EVALI-quintile tended to either ban all marijuana use or have [medical cannabis] laws prohibiting home cultivation,” the researchers wrote. Most states with adult-use laws “fell into the lower two quintiles for EVALI prevalence.”
The findings support what legalization advocates have long argued: Access to safe, legal cannabis is far preferable from a public health standpoint than sales on the illegal market, where products are unregulated and rarely tested for safety.
“Simply put, if the public can obtain products legally from reputable sources, there is less demand for illicit products,” reads the study.
One exception to the trend in the new study was Massachusetts, which despite having legal adult-use marijuana, was in the highest EVALI-quintile. The researchers noted that this “may be explained by the fact that Massachusetts’s [recreational marijuana] law went into effect almost two years before its first licensed dispensary opened, a delay that could have strengthened the informal market in the interim.”
Massachusetts also banned the sale of all vape products, including both cannabis and e-cigarettes, from late September to mid-December 2019, meaning the only way for consumers to access those products was through the illicit market.
Previous research has shown that states with legal, regulated cannabis markets saw lower rates of EVALI. But authors of the new report said their analysis “is the first to show a relationship between MM [medical marijuana] policy and EVALI.”
Medical marijuana states that allowed home cultivation had a 60% lower EVALI incidence compared to those forbidding it.the author writes
The authors acknowledged some limitations to their findings. One was data-gathering, as researchers relied on state-reported EVALI case data, which may be inconsistent from state to state. The illness itself is known variously as EVALI, VAPI (vaping-associated pulmonary injury) and VALI (vaping-associated lung injury).
The authors also acknowledged the findings are merely observational. “Although these findings are not causal, they provide direction to states that have passed or are considering MM legalization,” they wrote. “Specifically, to the extent that such policies affect licit and illicit marijuana use, policymaking not only must ensure the safety of legal products but also should consider potential impacts on illicit market offerings.
“To the extent that policymakers seek to leverage marijuana policies as a means to reduce the risk of future outbreaks,” the report concluded, “close attention to these laws’ details, particularly those expected to affect mode of use, will be critical.”
This piece is a part of a content-sharing arrangement between The News Station and Marijuana Moment.