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The Conference Board of Canada and The Globe and Mail are partnering to explore the relationship between career success and cannabis use. Employers and employees (both recreational and medical cannabis users, as well as non-cannabis users) are invited to participate in this study. (Employees interested in taking the survey can click on this link.; Employers interested in taking the survey can click on this link.) The data from these surveys will be aggregated and used to conduct analysis and create a report that will be presented Oct. 15, 2019 at a conference at The Globe and Mail Centre in Toronto.

One of the most notable benefits of Canada legalizing cannabis is that it has forced employers to talk about workplace substance use and safety. This may have been driven by the fear of what they will see with legalized cannabis. It has led employers to update fitness-for-duty policies, reconsider how they should test for alcohol and drugs, and talk to employees more about safety and being fit for duty.


The ability to know if someone is impaired by cannabis has been a growing worry since legalization. Employers know the risks of impairment, and are concerned that staff may use cannabis at work more often.

The National Academies of Sciences, Engineering, and Medicine’s Health Effects of Cannabis and Cannabinoids report found a connection between cannabis use and poorer learning, memory and attention. Other studies have shown that, in both occasional and regular users, tetrahydrocannabinol (THC), one of the active ingredients of cannabis, impairs attention, concentration and memory.


Because of cannabis’s intoxicating effects, employers in safety-sensitive sectors feel they need tools to reduce the risks that impairment might have on the safety of their workplaces.

Alcohol and drug testing in Canada has been at the centre of a debate around balancing safety and privacy. Not every employee who tests positive will have a substance use disorder. Those who are diagnosed with a disorder have a disability that is protected by human rights, similar to other medical conditions. Employers need to be sure their policies for alcohol and drug testing do not discriminate.

Employers must also think about their employees’ privacy when testing for alcohol and drugs. These are just some of the considerations that need to be addressed before introducing a policy on alcohol and drug testing.

For organizations that conduct alcohol and drug tests, the discussions tend to centre on finding the best test now that cannabis is legal. The most commonly used bodily fluid for drug testing is urine. Because THC is stored in fat cells and is slowly released over time, it remains in the urine of infrequent users for days, and weeks for more frequent or chronic users.

Since urine testing can’t differentiate between cannabis consumed today from cannabis consumed last week, employers have looked for other ways to help identify recent use, which is more likely linked to impairment.

Workplaces have been testing saliva for evidence of drugs for many years. With the legalization of cannabis, we’re seeing this method used more often. Saliva tests have been shown to detect recent use, are easier to supervise, and are less likely to collect a contaminated sample.

Testing saliva for cannabis is different than testing urine in that it doesn’t look for THC. It looks for the active cannabinoid delta-9-tetrahydrocannabinol (delta-9-THC). After cannabis is consumed (whether smoked, vaporized or eaten), delta-9-THC remains in the mouth for hours, depending on the amount used, the potency, how it was consumed, and the individual’s history of cannabis use.

So, a positive saliva test would show that a person has recently used cannabis, and recent cannabis use has been associated with impairment. The time-frame depends on the cutoff level used, but the test can detect cannabis from up to about 24 hours prior.

Employers are responsible for providing a safe workplace for employees and the community, and alcohol and drug testing can help discourage people from using drugs or alcohol at work. While safety is paramount, it’s also important for employers to consider the privacy rights of their employees.


Employers have many decisions to make about the best way to test for alcohol and drugs in the workplace. They must decide whether they need immediate test results or whether they can wait for a laboratory test. Immediate results, known as point-of-collection tests, are available for both urine and saliva tests.

Although having an immediate answer is ideal, these are screening tests and are not as accurate or reliable as laboratory-confirmed tests. It’s highly recommended that point-of-collection tests of urine or saliva be followed up with laboratory-confirmed tests.

The next decision is whether to use saliva testing and/or urine laboratory-confirmed testing. Saliva can be used to test for the same substances as urine, although some companies prefer to use urine to test for everything other than THC.

It’s best for an employer to consult an expert in the field who can develop a plan based on that company’s individual needs.

Bill Howatt is the chief of research for work force productivity at The Conference Board of Canada.

Melissa Snider-Adler is the chief medical review officer at DriverCheck Inc., a medical testing and assessment services company.

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