Canada's youth are using marijuana at a rate rivaled by few industrialized nations, with many parents who smoked in their youth dismissing it as the same harmless habit.

However, the current crop of cannabis has its own unique dangers, with many more youth admitted to hospital because of marijuana use than in the past.

The RCMP said genetic engineering has increased the amount of THC (the active ingredient) in marijunana from one to three per cent in the 1970s to ten to 12 per cent today, even as high as 32 per cent.

That's on top of the gallons of pesticides, fungicides and fertilizers used by grow-ops.

"To think marijuana today is the same benign thing, or the thing baby boomers used in the 1960s, is totally false," said Sgt. Pat Poutevin of the RCMP. "You don't have the same drug on the street anymore."

A survey of Ontario students said three per cent of them use cannabis daily, which equals about 31,000 students.

The number of teens in east Ontario who have gone to treatment centres because of marijuana use has gone up 51 per cent for boys and 53 per cent for girls in the last seven years.

One doctor at CHEO said he's seeing young people every day that suffer from side effects of regular marijuana use.

"We do have patients who come into the ER with a bad outcome from a single use of marijuana," said Dr. Mark Norris with CHEO's adolescent medicine unit. "We've had other patients who have come in with psychotic breaks from a single use of cannabis."

There's a growing body of evidence that suggests marijuana use increases the risk of a anxiety, depression and even schizophrenia.

With no evidence suggesting that cannabis causes schizophrenia, the risk among regular users who start to smoke at a young age is double that of those who don't.

Two years ago, regular user Nessa Blank said she was stressed and not sleeping well when she had a bad experience after smoking weed.

"I felt disoriented," she said. "When I was put in the hospital they didn't understand where I was coming from and they associated it with psychosis."

Still, her and her friends said the concerns about marijuana are overblown.

"I wouldn't consider any of my friends having psychosis when it comes to marijuana, and I have a lot of friends who do smoke," said Paul Dabarns.

With a report from CTV Ottawa's Joanne Schnurr