Residential proximity to agricultural pesticide applications and childhood acute lymphoblastic leukemia

Abstract

Ambient exposure from residential proximity to applications of agricultural pesticides may contribute to the risk of childhood acute lymphoblastic leukemia (ALL). Using residential histories collected from the families of 213 ALL cases and 268 matched controls enrolled in the Northern California Childhood Leukemia Study, the authors assessed residential proximity within a half-mile (804.5 meters) of pesticide applications by linking address histories with reports of agricultural pesticide use. Proximity was ascertained during different time windows of exposure, including the first year of life and the child's lifetime through the date of diagnosis for cases or reference for controls. Agricultural pesticides were categorized a priori into groups based on similarities in toxicological effects, physicochemical properties, and target pests or uses. The effects of moderate and high exposure for each group of pesticides were estimated using conditional logistic regression. Elevated ALL risk was associated with lifetime moderate exposure, but not high exposure, to certain physicochemical categories of pesticides, including organophosphates, cholorinated phenols, and triazines, and with pesticides classified as insecticides or fumigants. A similar pattern was also observed for several toxicological groups of pesticides. These findings suggest future directions for the identification of specific pesticides that may play a role in the etiology of childhood leukemia.

Maternal residential pesticide use and risk of childhood leukemia in Costa Rica

“…Our findings that exposure to pesticides sprayed on farms or companies near the home may be associated with higher odds of ALL are consistent with other studies that have examined associations between residential proximity to agricultural pesticide applications and childhood leukemia and other childhood cancers 7, 25, 26, 27, 28. Notably, previous studies have used exposure assessment methods such as geographic information systems to map pesticide use near the homes,25 analysis of pesticide use registry data,26 measurement of pesticide residues in home dust samples,27 or assessment of parental report of living in an agricultural area with pesticide use 7.…”

“…Notably, previous studies have used exposure assessment methods such as geographic information systems to map pesticide use near the homes,25 analysis of pesticide use registry data,26 measurement of pesticide residues in home dust samples,27 or assessment of parental report of living in an agricultural area with pesticide use 7. Associations between exposure to agricultural pesticides sprayed near the home and childhood leukemia could potentially be explained by the fact that, compared to children living in non‐agricultural areas, children living near farms may be disproportionately exposed to pesticides used in agriculture26, 29 through pathways including pesticide drift and the take‐home exposure pathway 30, 31, 32, 33…”

Novel Approaches in Genetic Toxicology of Pesticides by Applying Fluorescent in Situ Hybridization Technique

“…Their specific physiological role has mostly remained unclear though they are confirmed to be involved in immune functions, control of gene expression, cytoskeletal organization, secretion, absorption etc. Consequently, as discussed by Rull et al (2009) changes in AChE activity due to chronic exposure to anti-ChE compounds may induce amplification of AChE gene, and may affect cell proliferation and differentiation (Vidal, 2005). Both processes are closely associated with carcinogenesis, which may also provide a support for the results of previously cited epidemiological studies suggesting a correlation between carbamate exposure and increased risk of lymphoma.…”

Assessment of the level of damage to the genetic material of children exposed to pesticides in the province of Córdoba

“…Reynods, et al [34][35][36] and Rull, et al 37 demonstrated a relationship between childhood leukemia and the use of pesticides near living areas.…”