Childhood exposure to per- and polyfluoroalkyl substances (PFAS) and neurobehavioral domains in children at age 8 years.

Toxicological studies have raised concerns regarding the neurotoxic effects of per - and polyfluoroalkyl substances (PFAS). However, observational evidence from human studies investigating the association between childhood PFAS and neurobehavior is limited and remains unclear. To examine whether childhood PFAS concentrations are associated with neurobehavior in children at age 8 years and whether child sex modifies this relationship. We used data from 208 mother-child dyads in the Health Outcomes and Measures of the Environment (HOME) Study, a prospective pregnancy and birth cohort (Cincinnati, OH, USA). We quantified PFAS in child serum at 3 and 8 years. We assessed neurobehavioral domains using the Behavior Assessment System for Children-2 at 8 years. We used multiple informant models to estimate score changes per ln-increase in repeated PFAS concentrations. Childhood PFAS were not associated with Externalizing or Internalizing Problems at 8 years. However, we noted effect measure modification by sex, with higher scores in Externalizing Problems among males per ln-unit increase in perfluorononanoate (PFNA) at 3 years (β = 4.3 points, 95% CI: 1.0, 7.7) while females had lower scores (β = −2.8 points, 95% CI: −4.7, −1.0). More Internalizing Problems were observed among males per ln-unit increase in concurrent PFNA concentrations (β = 3.7 points, 95% CI: 0.7, 6.8), but not in females (β = −1.7 points, 95% CI: −4.6, 1.2). Childhood PFNA concentrations were associated with lower scores for attention problems and activity of daily living. While findings do not consistently support an association between childhood PFAS serum concentrations and neurobehavior, child sex may play a role in this relationship. • Childhood PFAS were not associated with externalizing or internalizing behaviors at 8 years. • Sex modified the relationship between childhood PFAS and neurobehavior, with males having worse scores. • Childhood PFNA was associated with poorer scores for activity of daily living and lower attention problems. • Prenatal PFAS were associated with more externalizing and internalizing problems even after adjustment for childhood PFAS. [ABSTRACT FROM AUTHOR]