More injured drivers test positive for cannabis than alcohol

Published on July 5, 2024 by Special to the oz.

Broken glass at a car crash scene Photo: Adobe stock/the oz.

By Erik Rolfsen

A University of British Columbia study of blood tests taken from injured drivers at emergency departments across Canada has revealed that cannabis (16.6%) has now narrowly edged out alcohol (16%) as the most commonly detected single substance.

While this is a new development, in most cases the cannabis level was not high enough to indicate impairment and increase crash risk. Drink driving remains a bigger problem in road safety and public health.

This report, on over 10,000 injured drivers from eight provinces between 2018 and 2023, is from an ongoing study that performs toxicology testing on blood samples from anonymized drivers who visited a participating hospital following a motor vehicle collision.

Nationally, the researchers found that 53.6 per cent of these injured drivers tested positive for at least one impairing substance.

Polysubstance use is another concern. Approximately one in five injured drivers (21%) tested positive for more than one impairing substance—another emerging trend the researchers are monitoring.

University of British Columbia