The requirement, which came into place in June 2019, stems from a policy decision made by Canada’s transport regulator. Transport Canada’s indicates that no person should work while “under the influence of any drug,” which naturally extends to cannabis and this is pertinent given the popularity of cannabis related products in the country (according to City News, retailers across Canada are struggling with a shortage of all cannabis related products).
With airlines, the revised Canadian Aviation Regulations stipulate that pilots, cabin crew, and air traffic controllers must have a certain level of “fitness for duty”. This means, in relation to cannabis, four weeks becomes the minimum time required to be free of cannabis before being allowed to work. As a minimum standard, airlines can impose even long periods of time by which they require their crews to be free from intoxicating products like cannabis.
The new ruling is in alignment with policies that already apply to the Department of National Defence and the Royal Canadian Mounted Police. It is likely that random urine samples will be required to be taken and sent for testing, in order to verify that airline personnel are confirming with the new policy.
The new ruling has been put in place based on scientific advice, and it is known that traces of tetrahydrocannabinol (THC) can remain in the body up to a month following last use. Urine tests are designed to detect the metabolite THC-COOH, which is produced when the liver breaks down THC.
A number of research papers show that THC remains in the body’s system for around 28 days, such as a paper published in Clinical Chemistry (“Impact of Prolonged Cannabinoid Excretion in Chronic Daily Cannabis Smokers’ Blood on Per Se Drugged Driving Laws”). Here the researchers from Brazil concluded: “Cannabinoids can be detected in blood of chronic daily cannabis smokers during a month of sustained abstinence. This is consistent with the time course of persisting neurocognitive impairment reported in recent studies.”
