Employment In Natural Resource Based Industries And Prostate Cancer Risk In Northeastern Ontario, Canada

Jeavana SRITHARAN, Cancer Care Ontario, Canada
DEMERS P. 1,2,3,4 , HARRIS S. 1,3,4 , COLE D. 4 , KREIGER N. 3,4 , SASS-KORTSAK A. 4 , LIGHTFOOT N. 5

1 Occupational Cancer Research Centre, Cancer Care Ontario, Toronto, Canada
2 Institute of Medical Science, University of Toronto, Toronto, Canada
3 Cancer Care Ontario, Toronto, Canada
4 Dalla Lana School of Public Health, University of Toronto, Toronto, Canada
5 School of Rural and Northern Health, Laurentian University, Sudbury, Canada

Objective Prostate cancer is the most commonly diagnosed cancer in North American men and there continues to be limited knowledge on preventable risk factors. There are a number of occupational exposures in natural resource based industries that are suspected to be related to prostate cancer risk. This study investigates associations between employment in natural resource based industries and prostate cancer. 
Methods Data were from a population-based, case-control study previously conducted in Northeastern Ontario. Incident cases (N=760) aged 45-85 years who were diagnosed between 1995 and 1998 were identified from the Ontario Cancer Registry. Controls (N=1632) were recruited from telephone listings and frequency-matched to cases by age. Lifetime occupational history was collected for all participants and logistic regression models were used to calculate odds ratios (OR) and 95% confidence internals (CI).
Results Elevated risks were observed for employment in forestry and logging industries (OR 1.87, 95% CI 1.32-2.73) and occupations (OR 1.71, 95% CI 1.24-2.35), which increased with duration of employment for ≥10 years. Elevated risks were also found for employment in wood products industries (OR 1.45, 95% CI 1.07-1.97) and paper and allied products industries (OR 1.43, 95% CI 1.03-2.00) and with duration of employment for ≥10 years. There were also few elevated risks in agriculture and mining related work, however these findings were not consistent across the study.
Conclusions There is evidence that prostate cancer risk may be associated with employment in several natural resource based industries, primarily in the forest industries. To further evaluate observed associations, studies should focus on natural resource based exposures.