Prenatal and childhood polybrominated diphenyl ether (PBDE) exposure and attention and executive function at 9–12years of age

Abstract

Objective California children’s exposures to polybrominated diphenyl ether flame retardants (PBDEs) are among the highest measured worldwide. We previously reported associations for prenatal and childhood PBDE exposures with decrements in attention, processing speed, fine motor coordination, and cognition in children at ages 5 and 7 years. Here, we investigate associations of PBDEs with attention and executive function at ages 9 to 12 years in the expanded CHAMACOS cohort. Methods We measured PBDEs in prenatal and child age 9 year serum samples for families enrolled in the study since pregnancy (“CHAM1”, N=321). In a subsequent cohort for which families were enrolled at child age 9 (“CHAM2”, N=301), we measured PBDEs in maternal and child samples collected at child age 9, and used predictive modeling to estimate prenatal exposure levels. We examined associations of measured and estimated PBDE concentrations on children’s attention and executive functioning at ages 9, 10½, and 12 years. Results Geometric means for prenatal and childhood ΣPBDE levels (sum of PBDE−47,−99,−100,−153) for the expanded CHAMACOS cohort were 26.3 and 63.2 ng/g lipid, respectively, and did not differ significantly between CHAM1 and CHAM2 families. We found consistent associations of prenatal exposure to PBDEs with poorer attention and executive function, measured with parent report and direct neuropsychological testing of the child. For example, using GEE models of repeated outcome measures at age 9 and 12, a 10-fold increase in prenatal ΣPBDE was associated with poorer response consistency on the Conners’ Continuous Performance Test II (β=2.9; 95% CI: 0.9, 4.8) and poorer working memory on the Behavioral Rating Inventory of Executive Function (β=2.5; 95% CI: 0.5, 4.4). Child age 9 ΣPBDE levels were associated with poorer parent-reported attention and executive function for girls but not boys. Conclusions Our results suggest that the prefrontal cortex may be a potential target for PBDE exposure and add to a growing literature showing that these ubiquitous toxicants may adversely affect neurodevelopment.

Effects of Polybrominated Diphenyl Ethers on Child Cognitive, Behavioral, and Motor Development

“…Studies that did not account for other chemicals were considered to be at high risk of bias. At the same time, the main effect remained in those studies that controlled for other chemical exposures [29,30]. While we know that including additional chemical exposures with a common (but unmeasured) source may lead to the amplification of bias due to residual confounding [40], a strong causal link between co-pollutants and the outcome favors including the co-pollutant in the model.…”

Prenatal polybrominated diphenyl ether and perfluoroalkyl substance exposures and executive function in school-age children

“…Maternal serum concentrations of BDE-47 were associated with more ADHD behaviors and hyperactivity in HOME Study children (Chen et al, 2014). Sagiv et al (2015) examined the relation between prenatal PBDEs and executive function in school-aged children (Sagiv et al, 2015). Adverse associations between measured prenatal ∑PBDEs (BDE-47, -99, -100, and -153) and BRIEF metacognition (β=3.3, 95% CI 0.4, 6.3) and global executive function (β=3.1, 95% CI 0.2, 6.04) were reported in children 9 years in the CHAMACOS Study (Sagiv et al, 2015).…”

“…Sagiv et al (2015) examined the relation between prenatal PBDEs and executive function in school-aged children (Sagiv et al, 2015). Adverse associations between measured prenatal ∑PBDEs (BDE-47, -99, -100, and -153) and BRIEF metacognition (β=3.3, 95% CI 0.4, 6.3) and global executive function (β=3.1, 95% CI 0.2, 6.04) were reported in children 9 years in the CHAMACOS Study (Sagiv et al, 2015). Adverse BRIEF composite scores were also reported with metacognition (β=2.7, 95% CI 0.2, 5.1) and global executive function (β=2.6, 95% CI 0.1, 5.1) among children 12 years with higher measured prenatal concentrations of ∑PBDEs.…”

“…Previous studies have reported conflicting results regarding effect modification by child sex with PBDEs or PFASs and neurodevelopment. In the CHAMACOS Study, no sex differences were reported for prenatal PBDEs and BRIEF assessed executive function (Sagiv et al, 2015). Further, no sex differences were found between maternal serum BDE-47 and child FSIQ in the HOME Study (Chen et al, 2014), and a previous study of in utero PFOA exposure reported that child sex did not modify the Numerical Operations score in the C8 Health Project (Stein et al, 2013).…”

“…Sagiv et al (2015) recently reported poorer executive function in children aged 9 and 12 years with measured concentrations of prenatal ∑PBDEs (BDE-47, -99, -100, and -153). While there are no studies on prenatal PFASs and executive function, Stein et al (2014) examined childhood PFOA concentrations at 2-8 years of age and executive function at 6-12 years.…”