Exposure to Multiple Pesticides and Risk of Non-Hodgkin Lymphoma in Men from Six Canadian Provinces

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International Journal of Environmental Research and Public Health (Impact Factor: 2.06). 06/2011; 8(6):2320-30. DOI: 10.3390/ijerph8062320
Source: PubMed


Non-Hodgkin lymphoma (NHL) has been linked to several agricultural exposures, including some commonly used pesticides. Although there is a significant body of literature examining the effects of exposure to individual pesticides on NHL, the impact of exposure to multiple pesticides or specific pesticide combinations has not been explored in depth. Data from a six-province Canadian case-control study conducted between 1991 and 1994 were analyzed to investigate the relationship between NHL, the total number of pesticides used and some common pesticide combinations. Cases (n=513) were identified through hospital records and provincial cancer registries and controls (n=1,506), frequency matched to cases by age and province of residence, were obtained through provincial health records, telephone listings, or voter lists. In multiple logistic regression analyses, risk of NHL increased with the number of pesticides used. Similar results were obtained in analyses restricted to herbicides, insecticides and several pesticide classes. Odds ratios increased further when only 'potentially carcinogenic' pesticides were considered (OR[one pesticide]=1.30, 95% CI=0.90-1.88; OR[two to four]=1.54, CI=1.11-2.12; OR[five or more]=1.94, CI=1.17-3.23). Elevated risks were also found among those reporting use of malathion in combination with several other pesticides. These analyses support and extend previous findings that the risk of NHL increases with the number of pesticides used and some pesticide combinations.

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    • "Non-Hodgkin's lymphoma (NHL) and work in agriculture are closely related. Associations of NHL in farmers with agricultural exposure, including animals[12345678910111213] and pesticides,[714151617181920] were reported all over the world. Most studies of NHL have been conducted among male farmers and farm workers. "
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    ABSTRACT: Objectives: The objective was to examine the association between non-Hodgkin's lymphoma (NHL) and farming-related activities, gender, pesticides exposure, and exposure to chemicals other than pesticides in Saskatchewan. Materials and Methods: Male and female study participants were taken from two separate case-control studies conducted in Saskatchewan province, Canada. A case was defined as any man or woman aged 19 years and older with a first diagnosis of NHL registered by the Saskatchewan Cancer Agency during the study period. Conditional logistic regression was used to fit the statistical models. Results: Farming exposure and exposure to pesticides-contaminated cloths were related to an increased risk of NHL. Exposure to pesticides was strongly associated with an increased risk of NHL, especially for men. Conclusion: For men, the incidence of NHL was associated with exposure to pesticides after adjusting for other independent predictors.
    Indian Journal of Occupational and Environmental Medicine 09/2013; 17(3):114-21. DOI:10.4103/0019-5278.130860
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    • "In this paper, we conduct a similar analysis for HL using data from the same study. Previous studies examining the risk from exposure to multiple pesticides have focused on NHL and have used broad groupings of pesticides such as insecticides, herbicides, and fungicides [11, 12]. These broad classes are comprised of many pesticides with varying chemical structures, which makes it difficult to identify individual pesticides that may increase risk or groups of pesticides with similar structure and/or function that may share a mechanism of carcinogenic action in humans. "
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    ABSTRACT: Purpose To determine the risk of Hodgkin lymphoma (HL) associated with exposures to multiple pesticides grouped by various classes, including carcinogenic classifications. Methods Data collected in the Cross-Canada Study of Pesticides and Health, a population-based incident case–control study in six provinces conducted between 1991 and 1994, were analyzed using unconditional logistic regression. Cases (n = 316) were identified through provincial cancer registries and hospital records. Controls (n = 1,506) were frequency-matched to cases by age (±2 years) within each province and were identified through provincial health records, telephone listings, or voter lists. The Cochran–Armitage test was used to check for trends within pesticide classes. Results Overall, there was an increase in the risk of HL among all subjects who reported use of five or more insecticides (OR 1.88, 95 % CI 0.92–3.87) and among subjects younger than 40 who reported use of two acetylcholinesterase inhibitors (OR 3.16, 95 % CI 1.02–9.29). There was an elevated odds ratio associated with reported use of three or more probably carcinogenic pesticides (OR 2.47, 95 % CI 1.06–5.75), but no increase in risk for use of possibly carcinogenic pesticides. The risk of HL from reported use of fungicides or any pesticides was greater for cases diagnosed before age 40 than for cases diagnosed at or after age 40. When analyses excluded proxy respondents, OR estimates strengthened in some circumstances. Conclusions This study found associations between HL and fungicides, insecticides, specifically acetylcholinesterase inhibitors, and pesticides previously identified as probable human carcinogens. These associations should be further evaluated, specifically in relation to age at diagnosis.
    Cancer Causes and Control 06/2013; 24(9). DOI:10.1007/s10552-013-0240-y · 2.74 Impact Factor
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    ABSTRACT: Studies of risk of non-Hodgkin's lymphoma have found both direct and inverse correlations with respect to solar ultraviolet (UV) doses. Reduced risk is generally found in midlatitudes, while increased risk is generally found at higher latitudes. It is suggested that reduced risk arises from vitamin D production from UVB irradiance, while increased risk arises from immunosuppression associated with UVA irradiance. The ratio of UVA to UVB increases with increasing latitude.
    Cancer Causes and Control 02/2012; 23(4):653-5; author reply 657-8. DOI:10.1007/s10552-012-9929-6 · 2.74 Impact Factor
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