Occupational and environmental exposures to diesel engine exhaust

CAREX Canada has identified diesel engine exhaust, which is a complex mixture of gases and particulates that are produced when diesel fuel combusts in a compression ignition engine, as a high priority for exposure reduction in Canadian workplaces. This is because almost one million Canadians are exposed to diesel engine exhaust at work.[1] The resulting impact on cancer is high; results from the Burden of Occupational Cancer project show that approximately 560 lung cancers, and possibly 200 urinary bladder cancers, are attributed to occupational diesel engine exhaust exposure each year.[2]

Furthermore, CAREX Canada’s environmental estimates indicate that levels in both indoor and outdoor air result in increased risks of cancer at a population level, making diesel engine exhaust the third highest priority indoor air exposure.[3]

CAREX Canada’s resources on the setting of an occupational exposure limit (OEL) for diesel engine exhaust in Canada

Setting an occupational exposure limit for diesel engine exhaust in Canada: This report examines the regulatory landscape for occupational diesel engine exhaust exposure in Canada, identifies key barriers and facilitators to setting and complying with occupational exposure limits, and recommends an OEL to protect worker health. Overall, it highlights the variability in occupational exposure limits that have been adopted in Canada for constituents of diesel engine exhaust and finds that few jurisdictions in Canada outside of the mining industry have an OEL for diesel engine exhaust, while none have adopted an OEL that reflects the current state of knowledge. CAREX Canada recommends that Canadian jurisdictions move towards an OEL based on elemental carbon of 20 µg/m³ for the mining industry and 5 µg/m³ for other workplaces to protect worker health. The report is available here (PDF).

Analysis of proposed policy to create an occupational exposure limit for diesel engine exhaust in Ontario: This analysis was conducted to better understand how the Ontario diesel engine exhaust OEL policy was brought forward and developed, to characterize the policy window for setting an OEL in Ontario, and to identify if a similar opportunity exists in other jurisdictions, specifically Alberta. Overall, it highlights how this policy proposal followed policy development models, and the importance of the role of the policy entrepreneur and policy maker. The report is available here (PDF).