Abstract

Infant Leukaemia is a rare haematological neoplasm associated with MLL gene rearrangements. Maternal exposure during pregnancy to pesticides, hormones, dipyrone, and topoisomerase-II DNA inhibitors and birth weight were associated risk factors. This is a hospital-based multicenter case-control study, and were interviewed mothers of 252 IL cases and of 423 controls. Data were obtained regarding environmental maternal exposure during periconceptional, pregnancy and breast-feeding periods, including exposure to pesticides. Unconditional logistic regression was performed and ORs on the association between maternal pesticides exposure and IL, including their 95% CIs, were ascertained after adjustment to hormonal intake during pregnancy, mother's age, mother's level of education, birth weight and infant's skin colour. An adjusted OR, 2.39, 95% CI 1.63 to 3.51 was observed for the association between IL and maternal exposure to pesticides during pregnancy, being higher for acute myeloid leukaemia (adjusted OR 3.50, 95% CI 2.01 to 6.11). The use of pyrethroids during pregnancy revealed an OR 2.18 (95% CI 1.44 to 3.29), while the use of other pesticides showed an OR 3.61 (95% CI 1.69 to 7.73). The reported household use of pesticides revealed an adjusted OR 2.25 (95% CI 1.48 to 3.43), and agriculture exposure showed an adjusted OR 9.26, (95% CI 2.82 to 30.4). Mixed exposure to different pesticides showed an adjusted OR, 3.83 (95% CI 1.33 to 11.0) and the exposure to different chemical classes revealed an adjusted OR, 8.87 (95% CI 1.55 to 50.6). The observed results seem to support the hypothesis that mothers' household use of pesticides and other contaminants may be involved in the aetiology of infant leukaemia.