Health effects of marijuana largely unknown, experts say

by Jasper Craven

BURLINGTON — Public health experts said Thursday there is inadequate information on the health effects of marijuana, but said lawmakers interested in legalizing the drug should perhaps look to tobacco regulation for guidance.

“When it comes to marijuana, particularly regarding the health consequences of marijuana use and the most effective public health policies to regulate this product, we are largely learning as we go,” said Shayla Livingston, a public health analyst at the Department of Health.

About 40 people attended the event, which was hosted by the Vermont Public Health Association. The crowd included Debby Haskins, executive director of the anti-legalization group SAM-VT, and Harry Chen, the state’s health commissioner.

Experts shared an assessment developed through analysis of 180 scientific studies on marijuana’s public health impacts. Much of the data came from states that have recently made recreational cannabis legal, such as Colorado and Washington.

“We take a data-driven, decision-making process where we want to lead with science, [and] use the best available data to inform policy decisions,” said Heidi Klein, the director of Health Surveillance at the Vermont Department of Health.

There is strong evidence to show that marijuana use impairs social functions, may increase psychotic symptoms and makes car accidents more likely.

Research is unclear about the relationship between marijuana use and brain function, anxiety, and skier safety.

“I was just on the phone today with someone in Colorado, and they said ‘yeah we would really like that, too,’” Livingston said about the lack of research on skiers who are under the influence of pot. “Similar tourist industry, similar problem. But we don’t have any research there yet.”

Vermont Health Commissioner Dr. Harry Chen. Photo by Erin Mansfield/VTDigger

At one point, Commissioner Chen asked Livingston if there was strong data regarding the potency of edible products.

“The research on edibles, particularly, is very limited,” Livingston said.

Colorado has recently developed equivalency equations between edible and smoked marijuana products.
“When we are looking at health effects [of edibles], it’s going to be very hard because most of the literature is on smoked marijuana,” Livingston said.

Livingston also presented a list of “critical unknowns,” a set of key questions about marijuana legalization in the state that are difficult to answer. They include how marijuana legalization will impact the number of consumers, the age at which consumers begin using and the number of days per week that consumers will use cannabis.

Kerry Cork, an attorney at the Public Health Law Center, spoke to the group via Skype, offering recommendations for how the state could look to tobacco laws when crafting marijuana legislation.
“As we’ve been looking at the growth of marijuana legislation, we’ve seen parallels in tobacco control legislation,” Cork said. “And also similar challenges in e-cigarette legislation.”

Cork’s recommendations included restricting flavored marijuana products, banning the public use of pot and defining specific regulations on the advertisement and promotion of marijuana products. She also said marijuana products should have health warnings and childproof packaging, much in the same way that tobacco products do.

With the data assessment complete, a group of stakeholders is scheduled to discuss a set of recommendations for the Legislature to consider when drafting marijuana laws.

The stakeholder group is composed of many factions, including doctors, marijuana advocates, medical dispensary employees and state education and public safety employees.

Livingston said it will be hard for all the voices to coalesce around one set of recommendations, but said she is confident a set of proposals would be ready to present to the Legislature convenes in January.

“It will be hard for all the stakeholders to agree, but it’s been easier because there’s an assumption built in that legalization will happen,” Livingston said.