Gestational PBDE concentrations, persistent externalizing, and emerging internalizing behaviors in adolescents: The HOME study

Background: Polybrominated diphenyl ethers (PBDEs) are ubiquitous environmental chemicals used as flame retardants in commercial and consumer products. Gestational PBDE concentrations are associated with adverse behaviors in children; however, the persistence of these associations into adolescence remains understudied. Objective: We estimated the association of gestational PBDE serum concentrations with early adolescent self- and caregiver-reported behaviors at age 12 years and determined the consistency with previously observed associations in childhood with caregiver-reported behaviors in a prospective pregnancy and birth cohort. Methods: We measured maternal serum concentrations of five individual PBDE congeners and created a summary exposure variable (E5BDE: 28, -47, -99, -100 and -153) during pregnancy. At age 12 years, we assessed behaviors for 237 adolescents using self- and caregiver-reports with the Behavioral Assessment System for Children-3 (BASC3). We used multivariable linear regression models to estimate covariate-adjusted associations of lipid standardized, log10-transformed gestational PBDE concentrations with BASC3 scores. We obtained estimates and 95% confidence intervals through a bootstrapping approach. We evaluated potential effect measure modification (EMM) of adolescent sex by examining sex-stratified regression models and estimating the EMM pvalues. Results: Gestational PBDE concentrations were positively associated with adolescent-reported BASC3 composite indices for inattention & hyperactivity (BDE-28, -47, -99, -100, E5BDE), internalizing problems (BDE-28, -47, -99), functional impairment (BDE-28, E5BDE), and emotional symptoms (BDE-28). Gestational PBDE concentrations were positively associated with caregiver-reported BASC3 composite indices for externalizing problems (BDE-28, -47, -99, -100, -153, E5BDE) and behavioral symptoms (BDE-99). For caregiver reported behaviors, we observed stronger associations with gestational BDE concentrations among males, especially for executive functioning (BDE-28, -47, -99, -100, E5BDE). Discussion: Gestational PBDE serum concentrations were associated with self-reported internalizing and externalizing behavior problems in early adolescence. Caregiver-reported externalizing behaviors recognized during childhood remain associated with gestational PBDE concentrations and persist into early adolescence. Internalizing behaviors were less recognized by caregivers.