In Utero and Childhood Pesticide Exposure Increases Childhood Cancer Risk

September 1, 2021 | A study published in Environmental Pollution finds the risk of acute childhood leukemia (AL) increases with prenatal and newborn exposure to pesticides (i.e., insecticides and herbicides). The study results support the hypothesis that chronic environmental pesticide exposure increases childhood leukemia risk up to two times. Maternal exposure has a stronger association with leukemia than childhood exposure. Insecticides and herbicides are of particular significance in increasing leukemia risk, especially for acute lymphoblastic leukemia. Childhood AL remains the second highest cause of child mortality following physical injury. Furthermore, childhood leukemia survivors can suffer from chronic or long-term health complications that may be life-threatening. The study results identify 55 studies from over 30 countries pertaining to over 200 different pesticide exposures from over 160,000 participants. Regardless of pesticide type, leukemia type, exposure timeframe, and population group, methodological studies demonstrate pesticide exposure increases the risk of childhood leukemia, particularly for infants. Maternal exposure to pesticides during gestation results in a more elevated leukemia risk for children than childhood (postnatal) exposure. Whether pesticide exposure is occupational or mixed, parental exposure to pesticides has the highest association with AL risk, including paternal (father) exposure. Exposure during pregnancy results in a 1.5 times greater risk of developing AL, with a 2.5 times increase in risk for acute lymphoblastic leukemia. [Karalexi, Maria et al. Exposure to pesticides and childhood leukemia risk: A systematic review and meta-analysis. Environmental Pollution. 285: 117376, 2021.]