In the lead up to the recreational (non-medical) use of cannabis being legalised in Canada in 2018, managers and business owners had many questions about the possible implications in the workplace. The most prevalent questions were ‘Will we see workers using cannabis at work?’, ‘How will we know if a worker is impaired?’ and, possibly the most important question, ‘Will legalisation of cannabis mean more mistakes and safety incidents?’
Identifying a knowledge and research gap around cannabis and the workplace, the Institute for Work & Health (IWH) conducted two research projects on the topic. The first looking at consumption habits and any associations between consumption and workplace injury risks, and the second looking at the use of cannabis to treat symptoms following work-related injury or illness.
The first study conducted multiple surveys – 4 months before legalisation, then at 9 to 11 months, two years and three years post-legalisation. Participants were included from across the country and from various industries.
The second study focused specifically on workers who had experienced a work-related injury or illness resulting in lost time and workers’ compensation.
Key findings –
- Cannabis use before and after legalisation – the study showed that about one in seven Canadian workers use cannabis on a daily or near-daily basis, including for therapeutic purposes. Use of cannabis has steadily increased.
- Workplace and non-workplace cannabis use – workers with less visible jobs and less restrictive workplace smoking rules were more likely to report before or at-work use. Having a supervisor skilled at identifying use or impairment was linked to a lower likelihood of workplace use. Workers in supervisory roles or safety-sensitive positions were more likely to report at-work cannabis use.
- Cannabis use and the risks of workplace injuries – use of cannabis at work (i.e. during a shift or up to two hours before) was associated with a doubling of the risk of a work-related injury. Use of cannabis outside of work showed no corresponding increase in risk, with the level of risk remaining the same as those who did not use cannabis.
- Reasons for cannabis use – about 40% of workers reported a work-based motivation for using cannabis e.g. coping with stress and relaxation. This may explain the higher reporting levels of those in supervisory or safety-sensitive roles.
- Cannabis use after workers’ compensation – more than 60% of workers using cannabis for work-related conditions did not receive any guidance from health-care providers on therapeutic cannabis use.
It is important to acknowledge that the term cannabis covers a wide array of products, various potencies, and various methods of consumption (inhalation, edibles, etc.), which result in different magnitudes and durations of impairment. The study could not identify whether the risk of injury differed according to the type of cannabis used or manner in which it was consumed.
It is important to recognise the differences between at-work cannabis use and non-work use and focus on impairment at work. Policies should centre on education, prevention and management as well as fitness for duty and creating an environment that encourages workers to come forward if they are impaired.
Read more: Cannabis use by workers before and after legalization in Canada - IWH
Medical Cannabis - Workers' Rights and Employer Obligations.