Some provinces are still grappling with how to best ensure the health and safety of Canadians in preparation for the upcoming legalization of recreational cannabis next year.

By July 1, 2018, Canadians across the country will likely be able to smoke marijuana recreationally and legally.

The Trudeau government tabled its marijuana legislation earlier this year with a number of restrictions, including, purchasers must be at least 18 years of age, a maximum of 30 grams can be carried at any time and households can grow up to four plants.

However, each province can independently determine the legal age, as well as how and where legal marijuana may be sold.

The Quebec government is reportedly setting the age limit at 18, while Ontario plans to set theirs at 19 to match the provincial drinking age.

Some health officials and safety advocacy groups say they are concerned about the proposed legislation.

“The adolescent brain is developing right up until the age of 25,” University of Montreal psychiatry professor Partricia Conrod told CTV Montreal.

“Our studies are also showing that early onset cannabis use is indeed a risk factor for psychosis-like experiences or symptoms, particularly among people who have a psychological vulnerability towards those types of symptoms,” she said.

University of Montreal neuropsychologist Dave Ellemberg added that regular cannabis consumption can permanently and negatively affect brain functions that are critical for learning.

“There’s research backing this up, that after a while the brain is less efficient, your memory is less efficient, you don’t focus and pay attention as well,” he said.

The Canadian Pediatric Association, on the other hand, has endorsed the age of 18, saying that the majority of brain development has already occurred by then. They have suggested, however, that there should be restrictions on quantity and THC potency up until the age of 25.

Meanwhile, an Ontario safety advocacy group is trying to convince Ottawa to delay the July deadline, arguing that rushing the process will pose health and safety risks.

“We’re going to see expanded use of cannabis. We’re not looking for prohibition, we’re looking for proper implementation and we’re not seeing that now,” President and CEO of the Ontario Safety League Brian Patterson told CTV Calgary.

Conrod adds that the legislation that is put in place must be carefully thought out or young people will turn to black markets.

“What was shown in Colorado is that rates of youth incarceration, school exclusion, did go up after they legalized cannabis,” she told CTV Montreal.

However, others have argued the new legislation along with the recommended guidelines, which were released in June, will promote sensible, safe and smart use of marijuana.

Dr. Benedikt Fischer, a senior scientist at the Centre for Addiction and Mental Health in Toronto, told CTV News Channel in an interview in June that the recommendations focus on what is within the realm of choice and control of the user thus making them less likely to risk their own health or the public’s.

“It will not make cannabis use safe… but actually safer. And that’s a small but important distinction,” he said.

Ontario already put forward their legislation earlier in September.

Quebec’s public health minister Lucie Charlebois is expected to introduce new legislation sometime in October and Alberta is expected to announce their framework next week.

British Columbia is still undergoing a consultation process that is scheduled to wrap up Nov. 1.

With files from CTV Montreal’s Angela Mackenzie and CTV Calgary’s Kathy Le