New Brunswick

Unregulated cannabis not as potent as advertised, study finds

Unlicensed cannabis is not as strong as you may think it is. 

A recent study compared illicit and legal cannabis products in New Brunswick for potency and contaminants

A recently published study found that the potency claims for illicit cannabis products in New Brunswick were often substantially inaccurate. (Robert Guertin/CBC)

Unlicensed cannabis is not as strong as you may think it is, acccording to a recently published study by the New Brunswick Research and Productivity Council.

Researchers comparing samples of illicit and legal cannabis products found that the claims of potency for illicit products were significantly less accurate. 

Diane Botelho, the research council's chief officer of science, said the study was done to find out whether there was any legitimacy to claims made about cannabis products on the illicit market being "better."

"Our scientists have been curious for a number of years now as to whether or not illicit cannabis products were equivalent to legal cannabis products with respect to health and safety as well as potency claims," Botelho said. 

Diane Botelho, chief officer of science for the New Brunswick Research and Productivity Council, was the lead author of a study that compared illicit and legal cannabis products in New Brunswick. (Diane Botelho)

According to the Canadian Cannabis Survey 2020, six to eight per cent of Canadians reported obtaining cannabis from illicit sellers.

Analysis of the illegal samples found that their potency often fell well below what was claimed. Conversely, potency claims for legal products were relatively accurate. 

For cannabis flower products, the analysis found that illicit products that were advertised with a 30 to 32 THC potency rate actually had an average potency of 13 to 22 per cent. Botelho said this raises concerns for users who want to have control over their dosage. 

"Users who are consuming cannabis and determining their optimal dosage based on the label claim of how much THC or CBD is in the product, if those claims are inaccurate on the illicit side then a consumer is actually not able to do so," said Botelho. 

Illegal edibles were also found to have a much lower potency rate than what was claimed. Cookie and chocolate bar products had less than half the THC that was advertised. 

However, illicit edible products still had an overall higher potency than regulated products. Current regulations dictate that a product may not contain more than 10 mg of THC, while some illicit products contain over 100 mg of THC.

"I think that 10 mg limit is something that is driving people to the illicit market and it's something perhaps we should have more conversation around," said Botelho. 

Unlicensed products contain harmful toxins

The study also found that illegal cannabis products were contaminated with microbes and pesticides. These chemicals were negligible or not found at all in legal products. 

"Pesticides are not allowed to be used in licensed products," Botelho said. "There are regulations in place in order to protect the safety of the consumer." 

Contaminants can have serious health implications, said Dr. Oyedeji Ayonrinde, a cannabis educator and associate professor at Queen's University school of medicine. For consumers who are using cannabis to treat medical conditions, the presence of harmful toxins could lead to neurological symptoms that are difficult for doctors to diagnose. 

"The paradox could be that while trying to reduce symptoms for medical purposes, they could actually trigger a completely different disorder, which could baffle doctors," said Ayonrinde. 

Dr. Oyedeji Ayonrinde is a cannabis educator and associate professor with Queen's University's Faculty of Medicine. (Oyedeji Ayonrinde)

The presence of toxic chemicals in unlicensed cannabis products is especially concerning for younger cannabis consumers who are still going through development, he added. 

However, persuading some Canadians to give up unlicensed cannabis might be difficult.

"Way before legalization, cannabis was from the grey market. There was something hip about cannabis being street and that's landed some legitimacy to it,"  Ayonrinde said.

The solution, he said, is for regulated sellers to stay price-competitive and to work on the branding of products to make them more appealing to consumers looking for something closer to what they're used to purchasing from illicit markets.


Nojoud Al Mallees


Nojoud Al Mallees covers economics for The Canadian Press. She's based in Ottawa.


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