Canadians' interest in cannabis-infused food is waning even as edibles are expected to become legal by mid-October, according to a new study that looks at changing attitudes toward marijuana.

The study out of Dalhousie University also found that 60 per cent of cannabis users continue to buy from the same supplier as they did before smoking pot became legal last year.

"The reason why they did that is for convenience, quality and most importantly price," lead author Sylvain Charlebois told CBC's Maritime Noon on Thursday.

"The price of cannabis in the black market is actually much lower, much more affordable than the legal cannabis."

The study found that 20 per cent of Canadians say they're worried about being seen buying cannabis. (Brett Ruskin/CBC)

Charlebois said he believes when edibles become legal, it could actually continue to fuel the black market.

"The regulatory framework presented by Health Canada is so restrictive that it won't entice manufacturers in Canada to produce edibles," he said.

"If there is appetite to consume edibles — no pun — people will actually look for that product. And we may actually see more products being imported into Canada illegally to support that demand."

Drop in legalization support

The study surveyed 1,051 Canadians over four days last month. The estimated margin of error is 3.1 per cent, 19 times out of 20. The aim was to compare attitudes before and after October 2018 legalization.

It found the number of Canadians in support of legalization in general fell by 19 per cent — and uncertainty about legalization rose by seven per cent. Only about six per cent of people reported starting using since legalization.

Of the 68 per cent of Canadians who were in favour of legalizing cannabis in 2017, 93 per cent of that group were willing to try an edible product. That dropped to 70 per cent in April.

"That's a significant drop," Charlebois said, adding it's probably for a number of different reasons — including media reports of specific incidents, such as when a four-year-old girl in Nova Scotia was hospitalized after accidentally ingesting cannabis-infused chocolate.

The study also found that Canadians are worried about edibles posing a greater risk to children (64 per cent) and pets (54 per cent).

Of those surveyed, 20 per cent said while they don't use cannabis now, they might consider edibles once they become legal. (Pong Pong/Shutterstock)

Charlebois said he believes Health Canada has been focusing on mitigating the risk of cannabis products and not actually educating people.

"We figured out that Canadians are mostly cannabinoid illiterate," he said.

People are also concerned about privacy: almost half said they're uncertain about their co-workers knowing they use cannabis recreationally.

The study also found edibles carry less stigma than other forms of cannabis, and 20 per cent of respondents said while they don't use cannabis now, they might consider edibles once they become legal.

Charlebois said in Colorado, where marijuana is also legal, 50 per cent of all sales are edibles.

Medicated High Chew edibles are shown on display and offered for sale at the cannabis-themed Kushstock Festival at Adelanto, Calif. (Richard Vogel/The Associated Press)

"The edible market in particular really has got a lot of people to consume cannabis, when really they didn't when only the dry stuff was legal. So we are expecting that to happen in Canada as well," he said.

While stigma wasn't something addressed in the 2017 study, Charlebois said the most recent findings suggest more than half of people believe retail facilities should be kept out of residential neighbourhoods. Less than 20 per cent said they're worried about being seen buying cannabis.

"The stigma was not as high or as strong as we thought it would be. However we have a long way to go from seeing cannabis become socially normalized in Canada," Charlebois said.

"And with restrictions, and in particular restrictions affecting edibles, that process may take much longer than expected."