(Photo by Avery Meeker on Unsplash)

MONTREAL, Quebec — For giant cities like New York, cars and traffic are just part of the urban landscape. New York is also one of the growing list of places across North America legalizing marijuana. Unfortunately for drivers (and even pedestrians) a new study finds those are two things that simply don’t mix. Canadian researchers find legalizing cannabis leads to an increase in fatal auto accidents; potentially putting hundreds of drivers in danger each year.

A team from McGill University analyzed legal recreational cannabis use and deadly motor vehicle collisions across the United States. They then applied the data to Canadian roads to find out how legalizing the drug may impact local roads.

“Analyses of data suggest that legalization of recreational cannabis in United States jurisdictions may be associated with a small but significant increase in fatal motor vehicle collisions and fatalities, which, if extrapolated to the Canadian context, could result in as many as 308 additional driving fatalities annually,” writes researcher Sarah Windle and her co-authors in the Canadian Medical Association Journal.

Legal marijuana is a growing problem for drivers

In Canada, researchers find cannabis consumption increased by three percent between 2018 and 2019, when the country legalized its use. According to Canadians reporting their own usage, that raised the number of people using marijuana to 17 percent.

Among cannabis users with a driver’s license, the study finds 13 percent admit driving within two hours of using marijuana. The total number of people admitting to getting on the road after recent cannabis use jumped from 573,000 to 622,000.

A 2012 analysis estimates cannabis-related auto collisions in Canada result in $1.1 billion worth of societal and economic damages annually. Drivers under the age of 34 are responsible for the majority of that damage.

Cracking down on driving under the influence

Researchers say health care providers need to enter the picture when it comes to educating the public about impaired driving.

“Health care professionals have an opportunity to educate patients about the safer use of cannabis products, including advising against cannabis use and driving (especially in combination with alcohol), with a suggested wait time of at least 6 hours before driving,” the study authors write.

The Canadian team adds government regulation will also need to play a big role in reducing the risk of injury due to drivers legally using marijuana.

“Implementation of impaired driving regulations and educational campaigns, including federal THC driving limits and public awareness of these limits, may contribute to the prevention of potential increases in cannabis-impaired driving in Canada,” the authors conclude.

About Chris Melore

Chris Melore has been a writer, researcher, editor, and producer in the New York-area since 2006. He won a local Emmy award for his work in sports television in 2011.

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