U of S researcher sets out risks of using legalized marijuana

As the legalization of marijuana approaches, there are still many questions about how the government plans to regulate the drug.

Michael Szafron, an assistant professor with the U of S School of Public Health who has been researching risk factors and demographics of marijuana usage in Canada prior to legalization, spoke Tuesday at a lecture and panel discussion about some of the lesser known negative aspects of recreational use.

“For me it’s really important that the public knows the benefits and the risks,” he said. “It’s not so black and white ... it’s this whole grey spectrum based on many factors.”

Szafron talked extensively about the explosive rates at which the percentage of THC in marijuana has risen since the 1960s and ‘70s — from around one to three per cent to 20 to 30 per cent — making the risk of Cannabinoid hyperemesis syndrome — or THC poisoning — which is characterized by vomiting, nausea and severe gastrointestinal discomfort, much more likely in heavy users.

THC is fat soluble, meaning even without excessive consumption users still run the risk of THC poisoning, he said.

Szafron suggests the government should consider regulating the amount of THC the same way they do with tobacco products, though he notes this would also present the possibility of people continuing to use illegal dealers to buy products with higher levels of THC than can be purchased in store.

Another risk in using marijuana, even in what most would consider moderation, include cognitive impairment and mental health issues like depression, bipolar disorder and schizophrenia, Szafron said. This risk increases when the user already has a family history of mental illness or is taking the drug while the brain is still in its development stages — which Szafron says occurs until around the early to mid 20s.

“There is a mounting body of evidence that people who are starting to use marijuana prior to when they finish cognitively developing will be at an extremely high risk,” he said. “A recent finding shows

It’s not so black and white ... it’s this whole grey spectrum based on many factors.

there is actually a genetic link ... and has shown the association between if a user has a family history of mental illness and a non-user has a family history of mental illness, the result is the user is more likely to develop mental health problems.”

Because there are currently no tests to determine whether or not a user has the variation on the specific gene that causes this problem, it’s impossible to find out if they would become more likely to develop these mental health issues, he said.

Szafron said policy development should not simply stop at mirroring tobacco and alcohol policies and should instead go further to address these additional risks, which he said could possibly put more strain on the health care system.

He also stressed that users should weigh these possibilities before assuming that since it is legal it is also safe.