We investigated the role of household exposure to pesticides in the etiology of childhood hematopoietic malignancies.
The national registry-based case–control study ESCALE (Etude sur les cancers de l’enfant) was carried out in France over the period 2003–2004. Population controls were frequency matched with the cases on age and sex. Maternal household use of pesticides during pregnancy and paternal use during pregnancy or childhood were reported by the mothers in a structured telephone questionnaire. Insecticides (used at home, on pets, or for garden crops), herbicides, and fungicides were distinguished. We estimated odds ratios (ORs) using unconditional regression models closely adjusting for age, sex, degree of urbanization, and type of housing (flat or house).
We included a total of 764 cases of acute leukemia (AL), 130 of Hodgkin lymphoma (HL), 166 of non-Hodgkin lymphoma (NHL), and 1,681 controls. Insecticide use during pregnancy was significantly associated with childhood AL [OR = 2.1; 95% confidence interval (CI), 1.7–2.5], both lymphoblastic and myeloblastic, NHL (OR = 1.8; 95% CI, 1.3–2.6), mainly for Burkitt lymphoma (OR = 2.7; 95% CI, 1.6–4.5), and mixed-cell HL (OR = 4.1; 95% CI, 1.4–11.8), but not nodular sclerosis HL (OR = 1.1; 95% CI, 0.6–1.9). Paternal household use of pesticides was also related to AL (OR = 1.5; 95% CI, 1.2–1.8) and NHL (OR = 1.7; 95% CI, 1.2–2.6); but for AL the relationships did not remain after adjustment for maternal pesticide use during pregnancy.
The study findings strengthen the hypothesis that domestic use of pesticides may play a role in the etiology of childhood hematopoietic malignancies. The consistency of the findings with those of previous studies on AL raises the question of the advisability of preventing pesticide use by pregnant women.