The Cross-Canada Study of Pesticides and Health (CCSPH) is a population-based case-control study that was conducted between 1991 and 1994 to explore associations between pesticides and four different types of cancer: non-Hodgkin lymphoma, Hodgkin lymphoma, multiple myeloma, and soft tissue sarcoma. The CCSPH includes men aged 19 years and older in six Canadian provinces with diverse agricultural practices and a variety of occupational and non-occupational exposures to pesticides. There were 513 incident cases with non-Hodgkin lymphoma; 316 with Hodgkin lymphoma; 342 with multiple myeloma; and 357 with soft tissue sarcoma. Cases were recruited from cancer registries in each province except in Quebec, where cases were ascertained from hospitals. All cases were matched by age (±2 years) and province to 1506 controls, who were randomly selected from health insurance records, computerized telephone listings, or voters’ lists. Postal and telephone questionnaires were used to collect data on pesticide use and other variables that may be related to these four cancer sites. The complete methodology of the CCSPH is described in McDuffie et al (2001).
The CCSPH is a rich dataset and numerous interesting associations have been demonstrated from over a dozen separate analyses that have been conducted since 2001. For example, studies have shown links between non-Hodgkin lymphoma and the herbicides dicamba, mecoprop, and 2,4-D, as well as the insecticides malathion, lindane, carbaryl, and DDT. The risk of non-Hodgkin lymphoma was also found to rise with use of an increasing number of potentially carcinogenic pesticides and some commonly used pesticide combinations. Other agricultural exposures, such as diesel exhaust, elevated the odds of non-Hodgkin lymphoma. Analyses of pesticides and Hodgkin lymphoma have generally shown few associations, however, insecticide exposure was related to higher odds of multiple myeloma and soft tissue sarcoma. Minimal links were observed from contact with farm animals. These studies also assessed non-occupational risk factors; for example, family history of cancer, which was found to increase the risks of all four cancer sites. Overall, these results have contributed to knowledge about the potential etiology of these cancers while paving the way for further research.
Between 1991 and 1994, data were collected on cases and controls using both postal and telephone questionnaires. These were modified from the telephone interview questionnaires that were used in similar studies of pesticide exposure and rare tumors in Kansas and Nebraska. The postal questionnaire was used to obtain demographic characteristics, medical history, detailed lifetime job history, and pesticide use, among other important factors that may be related to any of the four cancer sites that were included in the CCSPH. Telephone interviews were conducted with subjects who reported using any combination of pesticides for 10 hours or more per year during their lifetime, and a 15% random sample of those who used pesticides for less than 10 hours per year. Pesticide data were collected beginning with the broadest categories (e.g. occupations with potential pesticide exposure) followed by major chemical classes (e.g. herbicides), chemical groups (e.g. phenoxy herbicides), and individual compounds (e.g. 2,4-D). Both the postal and telephone questionnaires can be accessed below.
The CCSPH continues to be used to evaluate associations between agricultural exposures and the risk of non-Hodgkin lymphoma, Hodgkin lymphoma, multiple myeloma, and soft tissue sarcoma. The following analysis is currently in progress:
A systematic review: Using previously measured dermal exposure information to develop an occupational pesticide exposure assessment
Dermal exposure has been identified as the most significant route contributing to dose among workers who are occupationally exposed to pesticides. Epidemiologic studies that evaluate exposure to pesticides benefit from improved and transparent exposure assessments that aim to minimize misclassification. The objective of this study is to compile dermal pesticide exposure data (measurements, determinants of exposure) from published occupational studies for use in a retrospective exposure assessment. A systematic literature review of multiple databases has been completed to identify and screen studies on the topic of dermal pesticide exposure in occupational settings. Currently, we are extracting the dermal measurement data from each included study to estimate average exposure rates for each industry/job covered by this literature and to identify commonly reported dermal determinants of pesticide exposure (potential examples: pesticide handling task, personal protective equipment worn/type, application method, pesticide formulation, etc.).
- McDuffie HH, Pahwa P, McLaughlin JR, Spinelli JJ, Fincham S, Dosman JA, Robson D, Skinnider LF, Choi NW. Non-Hodgkin’s lymphoma and specific pesticide exposures in men: Cross-Canada Study of Pesticides and Health. Cancer Epidemiology, Biomarkers & Prevention 2001;10:1155-1163.
- McDuffie HH, Pahwa P, Spinelli JJ, McLaughlin JR, Fincham S, Robson D, Dosman JA, Hu J. Canadian male farm residents, pesticide safety handling practices, exposure to animals and non-Hodgkin’s lymphoma. American Journal of Industrial Medicine 2002;Supplement 2:54-61.
- Pahwa P, McDuffie HH, Dosman JA, Robson D, McLaughlin JR, Spinelli JJ, Fincham S. Exposure to animals and selected risk factors among Canadian farm residents with Hodgkin disease, multiple myeloma, or soft tissue sarcoma. Journal of Occupational and Environmental Medicine 2003;45:857-868.
- McDuffie HH, Pahwa P, Robson D, Dosman JA, Fincham S, Spinelli JJ, McLaughlin JR. Insect repellents, phenoxyherbicide exposure, and non-Hodgkin lymphoma. Journal of Occupational and Environmental Medicine 2005;47:806-816.
- Pahwa P, McDuffie HH, Dosman JA, McLaughlin JR, Spinelli JJ, Robson D, Fincham S. Hodgkin lymphoma, multiple myeloma, soft tissue sarcomas, insect repellents, and phenoxyherbicides. Journal of Occupational and Environmental Medicine 2006;48:264-274.
- Hossain A, McDuffie HH, Bickis MG, Pahwa P, et al. Case-control study on occupational risk factors for soft tissue sarcoma. Journal of Occupational and Environmental Medicine 2007;49:1386-1393.
- Karunanayake CP, McDuffie HH, Dosman JA, Spinelli JJ, Pahwa P. Occupational exposures and non-Hodgkin lymphoma: Canadian case-control study. Environmental Health 2008;7:44-53.
- McDuffie HH, Pahwa P, Karunanayake CP, Spinelli JJ, Dosman JA. Clustering of cancer among families of cases with Hodgkin lymphoma (HL), multiple myeloma (MM), non-Hodgkin lymphoma (NHL), soft tissue sarcoma (STS) and control subjects. BMC Cancer 2009;9:70-79.
- Pahwa P, Karunanayake CP, Spinelli JJ, Dosman JA, McDuffie HH. Ethinicity and incidence of Hodgkin lymphoma in Canadian population. BMC Cancer 2009;9:141-150.
- Karunanayake CP, Singh GV, Spinelli JJ, McLaughlin JR, Dosman JA, McDuffie HH, Pahwa P. Occupational exposures and Hodgkin lymphoma: Canadian case-control study. Journal of Occupational and Environmental Medicine 2009;51:1447-1454.
- Ghosh S, McLaughlin JR, Spinelli JJ, Dosman JA, McDuffie HH, Pahwa P. Multiple myeloma and occupational exposures: A population-based case-control study. Journal of Occupational and Environmental Medicine 2011;53:641-646.
- Hohenadel K, Harris SA, McLaughlin JM, Spinelli JJ, Pahwa P, Dosman JA, Demers PA, Blair A. Exposure to multiple pesticides and risk of non-Hodgkin lymphoma in men from six Canadian provinces. International Journal of Environmental Research and Public Health 2011;8:2320-2330.
- Pahwa P, Karunanayake CP, Dosman JA, Spinelli JJ, McLaughlin JR, et al. Soft tissue sarcoma and pesticide exposure in men: Results of a Canadian case-control study. Journal of Occupational and Environmental Medicine 2011;53:1279-1286.
- Pahwa P, Karunanayake CP, Dosman JA, Spinelli JJ, McDuffie HH, McLaughlin JR. Multiple myeloma and exposure to pesticides: A Canadian case-control study. Journal of Agromedicine 2012;17:40-50.
- Karunanayake CP, Spinelli JJ, McLaughlin JR, Dosman JA, Pahwa P, McDuffie HH. Hodgkin lymphoma and pesticide exposure in men: A Canadian case-control study. Journal of Agromedicine 2012;17:30-39.
- Pahwa M, Harris SA, Hohenadel K, McLaughlin JR, Spinelli JJ, Pahwa P, Dosman JA, Blair A. Pesticide use, immunologic conditions, and risk of non-Hodgkin lymphoma in Canadian men in six provinces. International Journal of Cancer 2012;131;2650-2659.
Kachuri L, Demers PA, Blair A, Spinelli JJ, Pahwa M, McLaughlin JR, Pahwa P, Dosman JA, Harris SA. Multiple pesticide exposure and the risk of multiple myeloma in Canadian men. International Journal of Cancer 2013;133:1846-1858.
Navaranjan G, Hohenadel K, Blair A, Demers PA, Spinelli JJ, Pahwa P, McLaughlin JR, Dosman JA, Ritter L, Harris SA. Exposures to multiple pesticides and the risk of Hodgkin lymphoma in Canadian men. Cancer Causes & Control 2013;24:1661-1673.
Ethics renewal letter
The University of Toronto Research Ethics Board approved continued analyses of the CCSPH. The protocol number can be found in the annual renewal approval letter.