Poultry and livestock exposure and cancer risk among farmers in the agricultural health study.

Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Cancer Causes and Control (Impact Factor: 2.96). 03/2012; 23(5):663-70. DOI: 10.1007/s10552-012-9921-1
Source: PubMed

ABSTRACT The purpose of this study is to evaluate cancer risk associated with raising animals as commodities, which is associated with a variety of exposures, such as infectious agents and endotoxins.
Information was available for 49,884 male farmers in the Agricultural Health Study, who reported livestock and poultry production at enrollment (1993-1997). Cancer incidence data were obtained through annual linkage to state registries. Using Poisson regression analyses, we evaluated whether the number and type of animals raised on the farm impacted cancer risk.
Overall, 31,848 (63.8%) male farmers reported raising any animals. Lung cancer risk decreased with increasing number of livestock on the farm (p trend = 0.04) and with raising poultry (Relative Risk (RR) = 0.6; 95% confidence interval (CI): 0.4-0.97). Raising poultry was associated with an increased risk of colon cancer (RR = 1.4; 95% CI: 0.99-2.0) with further increased with larger flocks (p trend = 0.02). Risk of non-Hodgkin lymphoma was also elevated in those who raised poultry (RR = 1.6; 95% CI: 1.0-2.4), but there was no evidence of increased risk with larger flocks (p trend = 0.5). Raising sheep was associated with a significantly increased risk of multiple myeloma (RR = 4.9; 95% CI: 2.4-12.0). Performing veterinary services increased the risk of Hodgkin lymphoma (RR = 12.2; 95% CI: 1.6-96.3).
We observed an inverse association between raising poultry and livestock and lung cancer risk and some evidence of increased risk of specific lymphohematopoietic malignancies with specific types of animals and performing veterinary services. Further research into associations between raising animals and cancer risk should focus on identification of etiologic agents.


Available from: Laura Beane Freeman, May 30, 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background: Because of unique exposures, studies among farmers may yield insights into the relationship between allergies and non-Hodgkin lymphoid neoplasms (NHL). We evaluated farm characteristics, allergic symptoms and conditions, and risk of NHL including specific subtypes in the Agricultural Health Study, a prospective cohort of farmers and spouses from North Carolina and Iowa. Methods: We identified 710 incident cases of NHL (including chronic lymphocytic leukemia and multiple myeloma) among 82,370 participants with baseline data on crop and animal exposures, including 454 cases among 52,850 participants with baseline data on recent allergy symptoms (rhinitis) and living on a farm during childhood. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using multivariable-adjusted proportional hazards models. Results: We observed reduced risks of NHL among farmers and spouses with rhinitis at baseline (HR=0.63, 95% CI=0.51-0.79), related to growing soybeans (HR=0.80, 95% CI=0.67-0.96), and among farmers who handled stored grains or hay (HR=0.66, 95% CI=0.52-0.82). Growing up on a farm was associated with increased NHL risk (HR=1.51, 95% CI=1.15-1.98). Results did not differ significantly by NHL subtype. Conclusions: Both the reduced risk of NHL among those with allergy symptoms and specific farm exposures in adulthood, and the increased risk among those who grew up on a farm suggest that the host immune response to agricultural allergens may influence NHL development. Impact: This prospective study is, to our knowledge, the first to investigate the relationship between allergy symptoms and NHL risk in farmers; confirmation of these findings in other farming populations is warranted. Copyright © 2015, American Association for Cancer Research.
    Cancer Epidemiology Biomarkers & Prevention 01/2015; 24(3). DOI:10.1158/1055-9965.EPI-14-1246 · 4.32 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Livestock breeders including poultry workers are exposed to various agricultural chemicals including pesticides and/or organic solvents. Multiple myeloma is a rare disease in Korea, and few reports have investigated the influence of occupational exposures on multiple myeloma occurrence. A 61-year-old male poultry farm worker presented with bone pain and generalized weakness. A bone marrow biopsy was performed, and he was diagnosed with multiple myeloma. The patient had worked in a poultry farm for 16 years and was exposed to various pesticides and organic solvents such as formaldehyde without any proper personal protective equipment. Results of the work reenactment revealed that the concentration of formaldehyde (17.53 ppm) greatly exceeded the time-weighted average (0.5 ppm) and short-term exposure limit (1.0 ppm) suggested in the Korean Industrial Safety and Health Act. This case report suggests that poultry workers may be exposed to high levels of various hazardous chemicals including pesticides and/or organic solvents. Numerous previous studies have suggested an association between multiple myeloma and exposure to agricultural chemicals; thus, multiple myeloma in this patient might have resulted from the prolonged, high exposure to these chemicals.
    12/2014; 26(1):35. DOI:10.1186/s40557-014-0035-y
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Prospective cohorts have played a major role in understanding the contribution of diet, physical activity, medical conditions, and genes to the development of many diseases, but have not been widely used for occupational exposures. Studies in agriculture are an exception. We draw upon our experience using this design to study agricultural workers to identify conditions that might foster use of prospective cohorts to study other occupational settings. Prospective cohort studies are perceived by many as the strongest epidemiologic design. It allows updating of information on exposure and other factors, collection of biologic samples before disease diagnosis for biomarker studies, assessment of effect modification by genes, lifestyle, and other occupational exposures, and evaluation of a wide range of health outcomes. Increased use of prospective cohorts would be beneficial in identifying hazardous exposures in the workplace. Occupational epidemiologists should seek opportunities to initiate prospective cohorts to investigate high priority, occupational exposures. Am. J. Ind. Med. 58:113–122, 2015.
    American Journal of Industrial Medicine 02/2015; 58(2):113-122. DOI:10.1002/ajim.22403 · 1.59 Impact Factor