TWO weeks ago a driver left a highway in Pennsylvania, crossed a median strip, became airborne and landed on a car on an adjoining road.
The two people inside the second car died.
The driver of the airborne car, who a friend had seen smoking just before driving, tested positive for synthetic cannabinoid drugs.
Dr Barry Logan, from the Center for Forensic Science Research and Education in the United States, spoke in Brisbane on Monday about the effects of these drugs, marketed as "legal highs", and how difficult it was to control and enforce their use.
He said the district attorney phoned him about the above crash to find out whether the drug test results meant the driver was under the influence when he caused the collision and whether his driving was consistent with using these drugs.
Dr Logan said there was a "significant probability the drug played some role in that collision" but the data about designer drugs was "significantly lacking" compared to research on other controlled drugs.
"In terms of having information to go to court and testify to a reasonable degree of scientific certainty, that information, frankly, for many of these drugs, doesn't exist," he said.
Dr Logan said his team, and others around the world, had been trying to collect data to understand the effects of drugs - such as Spice, K2, Smoke and Potpourri.
But he said it was a cat-and-mouse game where the manufacturers were always one step ahead, introducing many new blends every year to stay ahead of regulators.
Dr Logan said his team compared 12 suspected impaired driving cases, four involving collisions, and found police officers all put the observed behaviour down to the cannabis drug class.
He said the drivers generally had slurred speech, eyelid and leg tremors, body sway with elevated pulse and blood pressure.
Dr Logan said one man pulled over for erratic driving, including repeatedly weaving across the centre line on the road, admitted having a hit of Spice just before he was stopped.
He said another man who crashed into snow bank admitted to smoking Space just before driving and was adamant police could not do anything because it was completely legal.
Dr Logan said a German study had "consumption of synthetic cannabinoids could lead to impairment of similar or typical deficients caused by to cannabis use which are not compatible with safe driving".
But he said blood concentrations were unlikely to reflect the degree of the effect these drugs had on driving and laboratories responding to these cases must ensure scope for testing is dynamic and updated regularly.
Designer drugs is among the topics being discussed at the International Council on Alcohol, Drugs and Traffic Safety Conference in Brisbane.
DESIGNER DRUG DOWNS
- burning eyes
- blurred vision
- hot flushes
- thought disruption
- increase pulse and blood pressure
- loss of balance and motor co-ordination
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