A review study published in the International Journal of Environmental Research and Public Health has analyzed the available research and has concluded that the incidences of Non-Hodgkin lymphoma (NHL) are linked to pesticide use, but suggests that further investigation is required.
Non-Hodgkin’s lymphoma, also called non-Hodgkin lymphoma, is cancer that originates in your lymphatic system, the disease-fighting network spread throughout your body. In non-Hodgkin’s lymphoma, tumors develop from lymphocytes; a type of white blood cell. There are many different sub-types of non-Hodgkin’s lymphoma.
The incidences of Non-Hodgin lymphoma have increased substantially over the last thirty years, with environmental exposure viewed as the number one suspect responsible for the increase. Farmers in particular have demonstrated a high rate of some cancers suggesting that agricultural exposure to certain toxins including pesticides, fertilizers and chemicals may be the leading cause.
Several previous studies have linked the emergence of non-hodgins lymphoma to the increased use of pesticides. The review study analyzed the specific studies showing evidence of a positive correlation between NHL and
carbamate insecticides, organophosphorus insecticides, lindane, an organochlorine insecticide, and MCPA, a phenoxy herbicide. The researchers extracted data from 44 studies representing 12 countries. Estimates of NHL association were reported with 13 herbicide chemical groups, 28 herbicide active ingredients, five fungicide groups and 12 fungicide active ingredients and three insecticide groups and 40 insecticide active ingredients.
The researchers listed several ways through which pesticide exposure might be associated with NHL. Pesticides might cause chromosomal aberrations and genetic mutations, such as the t(14;18) translocation, which is a chromosomal abnormality, particularly common among cases of follicular lymphoma and diffuse large B-cell lymphoma. A second mechanism by which pesticide exposure may cause NHL is by altering cell mediated immune function. Indeed, immunological changes have been observed following short-term exposure to phenoxy herbicides (2,4-D and MCPA) among farmers.
The review study authors concluded that an examination of available studies supports the positive association between NHL and carbamate insecticies, OP insecticides, the phenoxy herbicide MCPA and lindane. Few papers reported associations with subtypes of NHL; however, based on the few that did, there were strong associations between certain chemicals and B cell lymphomas. There appears to be consistent evidence linking pesticide exposure in agricultural settings to an increase of NHL.
Leah Schinasi and Maria E. Leon.Non-Hodgkin Lymphoma and Occupational Exposure to Agricultural Pesticide Chemical Groups and Active Ingredients: A Systematic Review and Meta-Analysis. Int. J. Environ. Res. Public Health 2014, 11(4), 4449-4527