Pubdate: Sat, 19 Mar 2016
Source: Globe and Mail (Canada)
Copyright: 2016 The Globe and Mail Company
Contact:  http://www.theglobeandmail.com/
Details: http://www.mapinc.org/media/168
Author: John Ibbitson
Page: A6

DRIVEN TO DISTRACTION BY MEASURING POT USE

With the clock running, researchers struggle to find accurate ways to
determine at what point the drug impairs a motorist's abilities

The federal government faces a critical challenge as it moves to
legalize marijuana: It will be much harder to detect and charge people
who toke and drive than people who drink and drive. Some researchers
fear that it may be impossible.

Tetrahydrocannabinol (THC), the chemical in marijuana that creates the
buzz, acts very differently from alcohol. American states that have
legalized marijuana have struggled to come up with a legally
enforceable equivalent of .08 for alcohol consumption. There is no
marijuana equivalent to a modern breath-analysis machine, and it could
be years, if ever, before one reaches the market.

If the American experience is any guide, Canadians may have to accept
that, once marijuana is legal for recreational use, traffic deaths
will increase.

"If nothing is done, this is a major concern that could lead to
increased death and injuries," warns Andrew Murie, chief executive
officer of Mothers Against Drunk Driving Canada.

But he adds that there are steps that governments can take to reduce
the risk, and the Liberal federal government says it is committed to
taking them. The question is whether they will be enough.

According to a 2015 report by the Colorado State Police,
marijuana-related traffic deaths increased by 32 per cent in 2014, the
year it became legal for businesses to sell marijuana for recreational
use. Marijuana was a factor in 20 per cent of traffic fatalities,
double the number of five years before.

Although some of the data may be influenced by the fact that police
and researchers are testing for THC more than in the past, surveys
show that people of every age in Colorado smoke more pot than they
used to, now that it is legal. In Canada, annual school-based surveys
by the Centre for Addiction and Mental Health (CAMH) reveal that
teenagers are twice as likely to toke and drive as they are to drink
and drive (10 per cent versus 5 per cent).

We've been here before, and we've fought back. In the 1970s and 1980s,
federal and provincial governments successfully combined tough new
laws - the .08 limit, roadside checks, the breath test - and major
public awareness campaigns to deter rampant drinking and driving. It
worked. Nationally (excluding British Columbia), 1,094 people died in
accidents involving a drinking driver in 1995. In 2012, the figure was
563, less than half.

With marijuana, the tools of behaviour modification - the ads, the
school programs, the stories in media and such - will also be
available. But legal sanctions will be tougher to set CEO of Mothers
Against Drunk Driving Canada and enforce.

The problem, according to Erin Holmes, a research director at the
Washington-based Foundation for Advancing Alcohol Responsibility
(Responsibility.org), is that research into the effect of alcohol on
the body preceded policy and legislation. But, with legalized
marijuana, the law is getting ahead of the research.

"There just aren't the studies to say: Here is the nanogram level at
which every person would be so impaired that they could not safely
operate a motor vehicle," Ms. Holmes said in an interview. "We're just
not there with the research. And forensic toxicologists have gone so
far as to say we many never get there."

Washington and Colorado have set a limit of five nanograms of THC per
millilitre of blood in your system, although some experts consider
that level arbitrary.

However, new data will soon be available from Canada. At CAMH, based
in Toronto, Robert Mann is overseeing one of the most extensive
studies ever undertaken to determine how marijuana impairs driving
ability

For the past three years, moderate marijuana users 19 to 25 years old
have been asked to smoke as much as they would in a normal situation.
The volunteers were then subjected to a series of tests, including
driving in a highly accurate simulator.

"Some people say that 'I'm aware of the effects, I can compensate for
them, so I'm just as good or even maybe a safer driver' " after
smoking pot, Dr. Mann says.

The study will determine the truth of that assertion. Interim results,
Dr. Mann reports, suggest that distractions, such as counting backward
by threes while driving after smoking, can be particularly
problematic. Final results could be ready by the end of the year.

Another, possibly even bigger, problem is measuring THC levels in the
blood. There is no breath-analysis machine that would allow a roadside
test to determine marijuana use. Cannibex, a Vancouver-based company,
will soon begin trials on one that, if everything goes well, could be
ready for use in 2017. But the machine can read only whether marijuana
has been ingested in the past two hours. It can't determine levels of
concentration.

For now, police use the old-fashioned Standardized Field Sobriety Test
- - stand on one leg, walk. a straight line, follow the pencil - to
determine whether a driver is drug-impaired, which could eventually
lead to a blood test. But drivers who are only mildly impaired may
escape detection or conviction.

That doesn't mean that legalizing marijuana must result in an orgy of
impaired driving and carnage on the roads. As Ms. Holmes points out,
all of the lessons learned about deterring drunk driving are available
to deter drugged driving. "We don't have to invent the wheel, we're
not starting from scratch," she observes.

Mr. Murie believes that, among other measures, the new law should
authorize police to collect saliva samples, because there are machines
that can more accurately test THC levels using that method.

"I am confident that we can have the safeguards in place if we do
things right," Dr. Mann says. He maintains that legalization might
actually make it easier to have a testing and enforcement regime in
place, and to devote the necessary resources to change the behaviour
of marijuana users who drive.

The government said in a statement that a task force will study the
issue and make recommendations before any legislation is passed.

The risk of increased fatalities because of marijuana-influenced
driving is real. But legalization advocates insist that the risk can
be managed. To do so, we must convince each other that friends don't
let friends toke and drive.
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MAP posted-by: Matt