Surveillance of occupational cancer risks through linkage of WSIB claims to the Ontario Cancer Registry

Status: completed


The goal of this project was to develop a new way to monitor and measure workplace risk factors for cancer, by linking occupation and industry data to the Ontario Cancer registry via records of WSIB claims.


There are approximately 60 well-established workplace carcinogens. However, there are many more industrial chemicals and other agents that are suspected to cause cancer, and still more that have never been studied. Currently, Canada lacks any rapid means to assess whether there is an increased risk associated with an exposure or what the risk of cancer is among people with the same job or working in the same industry. The major challenge is that, although Canada collects very good information on every new cancer that is diagnosed, there is no way to identify where these patients worked. Having a way to link occupation and industry data to Cancer Registry data would allow researchers to identify jobs or substances that carry an increased risk of cancer.


When workers make claims to the Workplace Safety and Insurance Board (WSIB) for time lost, their claims contain information on their occupations and industries. These claims can be linked to records of cancer diagnoses held by Cancer Care Ontario to compare risks of cancer for different occupations and industries. The initial pilot project successfully adapted methods developed by researchers in Alberta and British Columbia for use in Ontario by linking a 20% sample of WSIB claims with Ontario Cancer Registry records.


Linking occupation and industry data to the Ontario Cancer Registry could allow researchers to investigate the cancer risk associated with exposure to previously unstudied industrial chemicals. It could also enable rapid assessment of the risk associated with various jobs in Canada, and highlight industries that require interventions to reduce exposure to workplace carcinogens.


The initial pilot study is now complete. The linkage was successful, and associations between occupational groups and cancers consistent with established risk factors were observed, including elevated risks of lung cancer in mining workers, mesothelioma in construction workers, and breast cancer among teachers. This indicates the feasibility of using the full linkage to provide a surveillance platform to explore occupational cancer risks.

An expansion of the linkage is being initiated to include a 100% sample of WSIB claims, extend follow-up and to include surveillance of other non-cancer chronic disease.


The initial pilot study was funded by a grant from the Ontario WSIB Research Advisory Council.


Anne Harris (Ryerson University)
Paul Demers (Occupational Cancer Research Centre and Cancer Care Ontario)
Mieke Koehoorn (University of British Columbia)
Christopher McLeod (University of British Columbia)
Jill MacLeod (Occupational Cancer Research Centre)
Anna Koné (Cancer Care Ontario)
Maisah Syed (Occupational Cancer Research Centre and University of Toronto)