TORONTO — Ontario adolescents are drinking, smoking and using cannabis and other recreational drugs at the lowest rates since the late 1970s, suggests a biennial survey of Grade 7 to 12 students by the Centre for Addiction and Mental Health.

But the 2017 survey released Thursday turned up a disturbing finding: almost one per cent of respondents in Grades 9 to 12 reported having taken illicit fentanyl in the previous year, raising a red flag given the opioid's involvement in hundreds of overdose deaths across the country.

Robert Mann, a senior scientist at CAMH and co-author of the Ontario Student Drug Use and Health Survey (OSDUHS), said declines over time in the proportion of adolescents using tobacco, alcohol and cannabis are a positive sign that public health messaging about the harms of such substances are getting through to young people.

In the last 20 years, the proportion of students who reported ingesting alcohol dropped to almost 43 per cent from 66 per cent, while smoking rates fell to seven per cent from 28 per cent, and cannabis use dropped to 19 per cent from 28 per cent.

Opioid use drops

Non-medical use of prescription opioids, monitored since 2007, declined to almost 11 per cent from about 21 per cent among those surveyed.

"One of the things we also see is that the onset of (substance) use is being delayed until later years. Now the onset tends to occur in later grades," said Mann, noting that about 37 per cent of 12th graders reported using marijuana.

The later that young people start using alcohol and other drugs, the less likely they are to develop problems with that use.Robert Mann

"And that's a very positive thing because we know that the later that young people start using alcohol and other drugs, the less likely they are to develop problems with that use, either currently or in the future."

Such long-term drops in usage point to successful efforts by parents, educators, public health officials — and students themselves — to address substance use and the problems it can create, agreed co-author Hayley Hamilton, a CAMH scientist.

"Nevertheless, we must remember that substance use among students can quickly begin to increase, as we have seen in the past, so a long-term and continued commitment to public health goals is necessary."

Legalization may pose new challenges

For example, the legalization of recreational marijuana in July could alter current patterns related to the psychoactive drug.

"There certainly have been concerns expressed that legalizing cannabis might send a message to young people that it's OK to be using it or it's OK for more people to be using it," Mann said.

However, when students were asked whether they agreed that adults should be legally able to purchase pot, responses were mixed, with about one-third giving a thumb's up, a third against the idea and the other third indicating they weren't sure.