Background: Developmental exposures to neurotoxic insecticides, as pyrethroids and chlorpyrifos are of growing concern.
Objective: To study associations between low prenatal and childhood exposure to pyrethroids and chlorpyrifos and motor skills at age 7.
Materials and methods: Data consisted of sub-samples of women and children from the Odense Child Cohort; 883 mother-child pairs with maternal urine collected around gestational week 28 and child motor function tests performed at age 7; 1166 children with urine samples collected at age 5 and motor function test at age 7. Motor function was assessed using threading lace and finger tapping tests from Movement Assessment Battery for Children. Metabolites of chlorpyrifos, 3,5,6-trichloro- 2-pyridinol (TCPy) and pyrethroids, 3-phenoxy-benzoic acid (3-PBA) were quantified in all urine samples. Linear regression adjusted for confounders was used to assess associations between urinary insecticide metabolite concentrations and motor function.
Results: Median maternal urinary concentrations of 3-PBA and TCPy were 0.21 μg/L and 1.63 μg/L; child concentrations at age 5 were 0.17 μg/L and 1.15 μg/L. No significant associations between maternal or childhood urinary concentrations and motor function at age 7 were found. However, higher maternal concentrations of 3-PBA and TCPy tended to correlate with longer threading lace times. Additionally, higher child TCPy concentrations were associated with fewer finger taps, although not significant.
Conclusions: In this cohort of pregnant women and children exposed to low levels of insecticides compared to populations living in areas with high residential or agricultural use, exploratory analyses suggested potential associations between urinary TCPy and 3-PBA concentrations during pregnancy and childhood and reduced motor function at age 7. Studies with larger exposure variability and older children are warranted to fully assess potential health impacts.
Copyright © 2025 The Authors. Published by Elsevier Inc. All rights reserved.