Despite the legalization of marijuana across Canada and in several U.S. states, the prevalence of positive drug tests among Canadian cross-border truck drivers has not changed significantly. Jonathan Davids, the corporate medical director at DriverCheck Inc., a leading provider of workplace medical testing in Canada, suggests that the stability of these rates underscores the vital importance of testing, education, and supervisor training in ensuring road safety.
“In regulated trucking, where drivers cross into the U.S. and must adhere to Department of Transportation (DOT) regulations, the positivity rates remain around 1%,” Davids explained. In contrast, for non-regulated trucking on domestic routes, positivity rates stand at about 7%. These figures come from “hundreds of thousands” of tests annually for regulated trucking companies and “tens of thousands” for their non-regulated counterparts.
From 2014 to 2018, the rate of positive tests in DOT-regulated trucking was 0.77%. Post-legalization, from October 2018 to the end of 2023, DriverCheck noted a slight increase of 1.29%, leading to a rate of 0.78%. Regulated trucking shows the lowest positivity rates for marijuana compared to other industries like aviation, construction, and health care, indicating effective regulation and enforcement, according to Davids.
After legalization, however, non-DOT positive test rates surged from 5.31% to 7.68%, marking a 44.6% increase. While drug testing continues to reveal more positive results than alcohol testing, the latter remains relatively low at 0.3% for regulated trucking and 0.4% for non-regulated trucking, with Davids highlighting a consistent trend across different sectors.
Quebec Observations
In Quebec, the Société de l’assurance automobile du Québec (SAAQ) reports low incidents of drug and alcohol impairment among heavy vehicle drivers between January 2018 and June 2024. Though the data focuses on arrests rather than convictions, it reflects a stable trend in driving violations. In this time frame, Quebec recorded 44 drug-related and 19 alcohol-related arrests among heavy vehicle operators.
Testing Methods and Challenges
The distinction between drug testing and impairment testing is critical, as a positive result does not confirm current impairment. Davids emphasizes that drug tests are not conclusive indicators of impairment, especially for substances like THC, which can linger in the system long after use. This confusion has contributed to driver shortages in the U.S. due to many drivers being suspended for positive marijuana tests.
Various testing methods exist, including urine and oral fluid tests, with each serving different purposes. DriverCheck combines these methods to enhance drug detection. Positive results are notably higher for reasonable cause testing, where supervisors suspect impairment, compared to post-accident tests. Davids insists on the necessity for managers to be trained in recognizing impairment to mitigate risks effectively.
Current Trends and Regulatory Changes
The FMCSA’s Drug and Alcohol Clearinghouse indicates that while marijuana remains the most detected substance in positive tests among truck drivers, there is a downward trend in reported marijuana positives. Preliminary data for 2024 suggests this decline may persist, reflecting an industry adapting to legal changes. As the U.S. considers reclassifying marijuana, implications for FMCSA regulations remain to be seen.
