Drugs showed up in toxicology tests in more than seven per cent of drivers in a random roadside survey in British Columbia, and about 33 per cent of fatally injured drivers tested for drugs across the country.
The figures were released Monday by the Canadian Centre on Substance Abuse, which wants to use the data to better understand who drives while under the influence of drugs.
But anti-drinking and driving messages and programs that were found to work in the 1980s can't just substitute the word "drugs," said Doug Beirness, a senior research and policy analyst.
"It's a different problem," he said from Ottawa.
"We need to launch prevention campaigns, we need to increase our enforcement efforts. We need to have rehabilitation programs. We need to have a comprehensive strategy to deal with the drugs and driving problem."
Gregg Thomson is already taking the message to high schools. His 18-year-old son died in a traffic accident with four other young men near Perth, Ont., in June 1999.
"From the police perspective, there was zero alcohol present. Zero. This was purely drugs that were being used that night. The driver and others were smoking pot, and that's how they pursued it," said Thomson, who's on the board of the anti-impaired driving organization MADD Canada.
But he fears that young people don't get it. He asks them if anybody thinks it's OK to drink and drive.
"And 100 per cent of the time, and I mean 100 per cent of the time, nobody says yes. Everybody gets the drinking and driving piece," he said.
But last week, he asked a class of 20 students to be honest about smoking drugs: "I said, 'Do you think it's OK if you' - and forgive the term here - 'if you blaze a couple and get behind the wheel?' And 16 of the kids put their hands up."
For the roadside survey, 2,840 vehicles were randomly stopped for driver interviews last spring: 569 in Vancouver, 708 in Saanich, 528 in Abbotsford, 500 in Prince George and 535 in Kelowna.
Eighty-six per cent of drivers provided a breath sample and 71 per cent gave an oral fluid sample. Among the key findings:
-9.9 per cent of drivers had been drinking. Less than three per cent of drivers had a blood alcohol level over the legal limit.
-7.2 per cent tested positive for drug use, with cannabis and cocaine being the drugs most frequently detected.
The fatalities study covered 12,978 drivers who died in crashes on public roadways in Canada from 2000 to 2007. Of the 5,929 who were tested for both alcohol and drugs, 18.5 per cent tested positive for a psychoactive drug, 21.9 per cent tested positive for alcohol only and 14.2 per cent tested positive for both alcohol and at least one psychoactive drug.
"They're not totally separate silos. People mix the two substances together, especially the young people. But there is a distinct group that just uses drugs and drives, and so it's a major issue," said Andrew Murie, CEO of MADD Canada.
But he said alcohol is by far still the No. 1 issue, and sometimes the centre appears to make drug-impaired driving seem worse than alcohol and "it's just not true."
"Not even close," he said. "When they talk about presence, it means any drug, prescription or illicit drug, and it's present in the body - doesn't mean it's impairing. When we talk about alcohol at roadside, we're talking about above levels that are considered impaired."
Beirness said the threshold at which drugs become a problem for drivers is a matter of continuing debate.
"There's some disagreement as to what is the absolute level of cannabis in the blood at which impairment and increased risk start. If you kind of weigh it all together, it comes down to about five nanograms per millilitre," he said.
"And you know, what we found in the study that we did in B.C. was that the cannabis levels in oral fluid that we found were often way above that five limit - if you accept that as an acceptable threshold."
Drug-involved fatal crashes were more likely than alcohol-involved crashes to occur during daytime hours on weekdays. In terms of other patterns, women tested positive for substances - both alcohol and drugs - at a lower rate than males, but when they did test positive it was most likely in the category of central nervous system depressants, said Erin Beasley, co-author of the studies.
"A bit of cannabis and a bit of cocaine in there, but definitely the CNS depressants are very big among the females. In contrast the males are kind of evenly distributed between the CNS depressants, the cannabis and the cocaine," she observed.
Beasley said younger drivers - except for the 16 to 18 year olds - were more likely to test positive for alcohol, but drugs were found at a rate that was consistent across all ages.
"With our young people ... the 16- to 18-year-olds, we're not seeing as much of the alcohol in that age group. They seem to have gotten the message about alcohol; not so much with the drugs. And in particular, we're seeing cannabis. Cannabis is very big among the young drivers."
"Cannabis use declines with age among our fatally injured drivers. Among the middle-aged drivers, around the 40-year-olds, that's where your CNS depressants are predominant, particularly your cocaine."
Amendments to the Criminal Code that took effect in July 2008 gave police the power to demand that a driver suspected of being impaired by drugs submit to a field sobriety test and later be evaluated by an officer trained in the Drug Evaluation and Classification program.
RCMP Sgt. Evan Graham, national co-ordinator of the program, said police officers are alert for signs such as drivers weaving side to side, crossing the centre line, driving too fast or too slow, or seeing a beer or marijuana cigarette being passed around in a vehicle.
Once the vehicle is stopped, other evidence might include the smell of cannabis, the actual cigarette, drug paraphernalia or pills and bottles in the car. The driver might have eyes that are watery or bloodshot, the whites of the eyes might be pink, or the pupils might be dilated in daylight or constricted at night.
After a field sobriety test, there would be a fork in the road as to whether it proceeds as an alcohol or drug investigation.
"If it's drugs, they're taken back to the police station, where in a controlled environment they are evaluated by a trained evaluator."
He said 591 officers have been trained nationwide as drug evaluators.
"If the impairment is there, then we look at clinical indicators, such as the pupil size under different lighting conditions, how the pupils react to light, their blood pressure, their pulse and their body temperature. Using those indicators, we can put the person into one or more of seven drug categories, or conversely come up with a decision that the person isn't impaired, or is possibly impaired by fatigue," he said from Ottawa.
"If we believe a person is impaired by a drug ... then we can demand a bodily fluid sample, that being blood, urine or oral fluid, which, when the sample is collected is sent to a forensic lab where they'll do an analysis."
As for regional differences, methamphetamine is far more prevalent in Western Canada than on the East Coast, he noted. On the East Coast, he said officers see more use of prescription narcotics than they would in British Columbia, where heroin is more prevalent.
"Every province has their own little quirks as far as drug usage and what the drug of choice is."
Police forces don't have sufficient manpower to look at every potential case, "but we're working towards that," Graham said.
"This is for all intents and purposes a new tool for the police and it takes time to get it ramped up and to have the courts accept it. So by utilizing this, we're going to make the roads safer for everyone, and hopefully we'll save some lives."