In vivo studies have demonstrated that prenatal or neonatal exposure to polybrominated diphenyl ethers (PBDEs) causes developmental neurotoxicity. However, there is a lack of human data. Our hypothesis was that PBDEs would result in lower infant neurodevelopment scores. This is a post-hoc analysis of previous studies. Fourteen PBDEs in 70 breast milk were analyzed using a high-resolution gas chromatograph/high-resolution mass spectrometer. Infant neurodevelopment at the age of 8-12 months was determined using the Bayley Scales of Infants and Toddlers Development, third edition (Bayley-III). The median of Sigma14PBDEs (the sum of 14 PBDE congeners) was 2.92 ng/g lipid. The Sigma14PBDE concentrations were not correlated with Bayley-III scores on cognitive, language, motor, social-emotional, or adaptive behavior scales. A significantly inverse association between brominated diphenyl ether (BDE)-209 and the cognitive scale was found after multivariate stepwise linear regression analyses (B=-0.007, adjusted R=-0.224, p=0.032). In contrast, the language scale was positively correlated with BDE-196 (B=0.096, adjusted R=0.315, p=0.002). Our results are consistent with most in vivo studies, suggesting that prenatal or postnatal exposure to BDE-209 potentially delays the neurological development.
