Status: completed

Purpose:

The goal of this project was to identify specific occupations, industries, or exposures that lead to an increased risk of cancer, by using a database containing information from the 1991 long form census linked to the Canadian Cancer Registry data. Relationships of interest include:

lung cancer in welders
occupations and ovarian cancer
cancer among wood workers
cancer among firefighters and police
shiftwork and cancer
cancer in agricultural workers
occupational physical activity and colorectal cancer

Significance:

There are approximately 60 well-established workplace carcinogens identified by the International Agency for Research on Cancer (IARC). However, there are over 100 industrial chemicals and other agents that are suspected to cause cancer, and many more have never been studied. Currently, Canada lacks any rapid, low cost means to assess whether there is an increased risk associated with an exposures, occupations or industries. The major challenge is that, although Canada registers every new cancer that is diagnosed, information on occupation and workplace exposures is not included in these records. Having a way to link occupation and industry data with data from the Canadian Cancer Registry would allow researchers to identify jobs or substances that carry an increased risk of cancer.

Methods:

Statistics Canada linked data from the 1991 long form census to the Canadian Cancer Registry, a national database created with data from all the provincial and territorial tumour registries. The resulting database includes 2.7 million people. Analyses were undertaken to identify at-risk groups by occupation and industry, and to examine risks associated with certain occupational exposures.

Implications:

These analyses contribute to the recognition of causes of cancer that can then be targeted for prevention efforts.

Funding:

Linkage of the 1991 census to the Canadian Cancer Registry was funded by the Canadian Institute for Health Information and Health Canada. Analyses were funded by a WSIB Research Advisory Council grant for 2012-2015.

Investigators:

Jill MacLeod (Occupational Cancer Research Centre)
Paul Demers (Occupational Cancer Research Centre and Cancer Care Ontario)
Anne Harris (Ryerson University)
Manisha Pahwa (Occupational Cancer Research Centre)
Garthika Navaranjan (Occupational Cancer Research Centre)
Linda Kachuri (Occupational Cancer Research Centre)
Anna Koné (Cancer Care Ontario)
Marcella Jones (Occupational Cancer Research Centre)
Trevor Van Ingen (Occupational Cancer Research Centre)
Eliane Kim (Occupational Cancer Research Centre)
Jeavana Sritharan (Occupational Cancer Research Centre)
Kishor Hadkhale (University of Tampere)

Collaborators:

Michael Tjepkema (Statistics Canada)
Paul Peters (Statistics Canada)

Publications:

Sritharan J, MacLeod J, Harris SA, Cole DC, Harris A, Tjepkema M, Peters PA, & Demers PA. (2018). Prostate cancer surveillance by occupation and industry: the Canadian Census Health and Environment Cohort (CanCHEC). Cancer Medicine (in press).
Pahwa, M., Harris, M.A., MacLeod, J., Tjepkema, M., Peters, P.A., Demers, P.A. (2017). Sedentary work and the risks of colon and rectal cancer by anatomical sub-site in the Canadian census health and environment cohort (CanCHEC), Cancer Epidemiology, 49:144-51.
Kachuri, L., Harris, M.A., MacLeod, J., Tjepkema, M., Peters, P.A., Demers, P.A. (2017). Cancer risks in a population-based study of 70,570 agricultural workers: results from the Canadian census health and Environment cohort (CanCHEC), BMC Cancer, 17:343
Hadkhale, K., MacLeod, J., Demers, P.A., Martinsen, J.I., Weiderpass, E., Kjaerheim, K., Lynge, E., Sparen, P., Tryggvadottir, L., Harris, M.A., Tjepkema, M., Peters, P.A., Pukkala, E. (2017). Occupational variation in incidence of bladder cancer: a comparison of population-representative cohorts from Nordic countries and Canada, BMJ Open, 7.
MacLeod, J., Harris, M.A., Tjepkema, M., Peters, P.A., Demers P.A. (2017). Cancer risks among welders and occasional welders in a national population-based cohort study: Canadian census health and environmental cohort, Safety and Health at Work, 8(3):258-66.
Jones, M.K., Harris, M.A., Peters, P.A., Demers P.A. (2014). Prostate cancer and occupational exposure to whole-body vibration in a national population-based cohort study. American Journal of Industrial Medicine, 57(8):896-905.