Is precarious employment an occupational hazard? Evidence from Ontario, Canada.

Objectives: To examine the association between precarious employment and risk of occupational injury or illness in Ontario, Canada.

Methods: We combined accepted lost-time compensation claims from the Workplace Safety and Insurance Board with labour force statistics to estimate injury and illness rates between January 2016 and December 2019. Precarious employment was imputed using a job exposure matrix and operationalised in terms of temporary employment, low wages, irregular hours, involuntary part-time employment and a multidimensional measure of 'low', 'medium', 'high' and 'very high' probabilities of exposure to precarious employment. Negative binomial regression models examined exposure to precarious employment in relation to risk of occupational injury or illness.

Results: After adjusting for age, sex and year, all indicators of precarious employment were associated with increased risk of injury or illness. Workers with 'high' and 'very' high' exposure to precarious employment presented a nearly threefold risk of injury or illness (rate ratio (RR): 2.81, 95% CI 2.73 to 2.89; RR: 2.82, 95% CI 2.74 to 2.90). Further adjustment for physical demands and workplace hazards attenuated associations, though a statistically and substantively significant exposure-outcome relationship persisted for workers with 'high' and 'very high' exposures to precarious employment (RR: 1.65, 95% CI 1.58 to 1.72; RR: 2.00, 95% CI 1.92 to 2.08).

Conclusions: Workers exposed to precarious employment are more likely to sustain a lost-time injury or illness in Ontario, Canada. Workplace health and safety strategies should consider the role of precarious employment as an occupational hazard and a marker of work injury risk.