Epidemiologic Studies in Agricultural Populations: Observations and Future Directions

Abstract

This paper reviews epidemiologic studies of cancer among agricultural populations to identify possible associations and to provide a focus for future investigations. Meta-analyses of mortality surveys of farmers find excesses of several cancers, including connective tissue, non-Hodgkin lymphoma, Hodgkin disease, and multiple myeloma and cancers of the skin, stomach and brain and deficits for total mortality, heart disease, total cancer, and cancers of the esophagus, colon, lung and bladder. Meta-analyses of studies of individual cancers also support these findings indicating a need to identify exposures and lifestyle factors that might account for this mortality pattern. Although cancer studies of other occupations that might have pesticide exposures in common with farmers show some similarities with observations among farmers, the overall patterns are quite different. This suggests that pesticides are not likely to fully explain the cancer and other disease patterns observed among farmers. Because exposures vary by type of farm operation, exposures for individual farmers can differ considerably. Studies in the future need to focus on the full range of exposures to fully understand the cancer pattern in farmers.

Adipose tissue concentrations of persistent organic pollutants and total cancer risk in an adult cohort from Southern Spain: Preliminary data from year 9 of the follow-up

“…In addition, we did not take into account co-exposures to other chemicals, such as polybrominated diphenyl ethers (PBDEs) or phthalates, which may also be involved in the development of cancer. The relationship between the human exposure to other environmental pollutants and total cancer has been assessed in previous epidemiological studies (Blair and Freeman, 2009;Mink et al, 2012). We highlight the positive Spearman correlations observed between all POPs in our study; therefore, the associations found with single chemicals may be surrogates of exposure to other more toxic agents or even to mixtures of POPs with similar physicochemical characteristics (Arrebola et al, 2013b;Brauner et al, 2012b).…”

Organic Foods: Health and Environmental Advantages and Disadvantages

“…45 46 Chronic exposure among farm workers has been associated with numerous adult health problems, including respiratory problems, memory disorders, dermatologic conditions, depression, neurologic deficits including Parkinson disease, miscarriages, birth defects, and cancer. [47][48][49][50] Prenatal organophosphate pesticide exposure has been associated with adverse birth outcomes, such as decreased birth weight and length 51 and smaller head circumference. 52 A large prospective birth cohort study that measured pesticide exposure in pregnant farm workers in California and followed their offspring found lower mental development index scores at 24 months of age 53 and attentional problems at 3.5 and 5 years of age.…”

“Fortis Et Liber” Unless You Are a Farm Worker

“…This comparative approach is warranted because farm workers share three important similarities to firefighters around occupational disease. First, farm workers face a heightened risk of various kinds of cancers, including melanoma, non-Hodgkin's lymphoma, leukemia, and multiple myeloma as well as brain, cervical, esophageal, oral, prostate, and stomach cancers (Blair & Freeman, 2009;Blair & Zahm, 1995;Fincham, Hanson, & Berkel, 1992;Mills, Dodge, & Yang, 2009). Second, this heightened risk is likely the result of occupational exposures to pesticides, solvents, exhausts, dusts, and microbes.…”