Prenatal Exposure To Per- And Polyfluoroalkyl Substances And Childhood Executive Function And Behavior Problems

Abstract

Background: Evidence from animal studies suggests that per- and polyfluoroalkyl substances (PFAS) may act as developmental neurotoxicants, but epidemiological evidence is limited and inconsistent. We examined prenatal PFAS exposure in relation to executive function and behavior problems in children. Methods: We studied 613 mother-child pairs from Project Viva, a longitudinal pre-birth cohort enrolled 1999-2002. We measured perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), and perfluorononanoate (PFNA) concentrations in maternal plasma from early pregnancy (median=9.6 weeks gestation; range: 5.6-20.9). At median age 7.8 years, classroom teachers evaluated children using the Behavior Rating Inventory of Executive Function (BRIEF) and the Strengths and Difficulties Questionnaire (SDQ). BRIEF results were assessed as standardized T-scores (mean=50, standard deviation=10), SDQ results as total difficulties scores (possible range: 0-40); for both, higher scores indicate greater problems. Using linear regression models, we estimated associations of PFAS concentrations with BRIEF and SDQ scores, adjusted for gestational age at blood draw, maternal kidney function, parity, pre-pregnancy body mass index, and other potential confounders. Results: Median (25-75th percentile) PFAS concentrations (in ng/mL) were 5.6 (4.0-7.6) (PFOA), 24.8 (18.3-32.9) (PFOS), 2.4 (1.6-3.7) (PFHxS), and 0.7 (0.5-0.9) (PFNA). Compared with children born to mothers in the lowest quartile of PFOS plasma concentrations, those in the highest quartile had higher scores on the SDQ (1.2 points; 95% confidence interval (CI): -0.1, 2.5) and BRIEF Metacognition Index (2.4; 95% CI: 0.1, 4.7). Relationships of prenatal PFOA, PFNA, and PFHxS concentrations with BRIEF and SDQ scores were less consistent. Conclusions: Higher prenatal exposure to PFOS may be associated with greater executive function and behavior problems in a cohort of United States children.