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

Abstract

Polybrominated Diphenyl Ether (PBDE) flame retardants are environmental chemicals that cross the placenta during pregnancy and have shown evidence of neurotoxicity. As the in utero period is a sensitive developmental window, such exposure may result in adverse childhood outcomes. Associations between in utero PBDE exposure and neurodevelopment are found in animal models and increasingly in human population studies. Here, we review the epidemiological evidence of the association between prenatal exposure to PBDEs and motor, cognitive, and behavioral development in infants and children. Published work suggests a negative association between PBDE concentrations and neurodevelopment despite varying PBDE congeners measured, bio-specimen matrix used, timing of the biological sampling, geographic location of study population, specific developmental tests used, age of children at time of testing, and statistical methodologies. This review includes 16 published studies that measured PBDE exposure in maternal blood during pregnancy or in cord blood at delivery and performed validated motor, cognitive, and/or behavioral testing at one or more time during childhood. We evaluate possible mediation through PBDE-induced perturbations in thyroid function and effect measure modification by child sex. While the majority of studies support an adverse association between PBDEs and neurodevelopment, additional research is required to understand the mechanism of action, possibly through the perturbations in thyroid function either in the pregnant woman or in the child, and the role of biologically relevant effect modifiers such as sex.

The association between prenatal concentrations of polybrominated diphenyl ether and child cognitive and psychomotor function

“…It is still unclear if PBDE exposure may affect child motor control. Most studies have not detected significant associations, 16 – 18 , 24 , 41 and similarly, our study is in line with that research. However, two studies suggested a negative association between motor development and PBDE exposure.…”

“…The association between child attention and PBDE exposure has been well investigated. 16 Previous animal studies suggested that PBDE exposure can affect sustained attention and can increase hyperactivity. 42 , 43 Similarly, studies in children have detected correlations between PBDE exposure and child attention deficits.…”

A Prospective Study of Environmental Exposures and Early Biomarkers in Autism Spectrum Disorder: Design, Protocols, and Preliminary Data from the MARBLES Study

“…According to recent reviews and a meta-analysis, neurodevelopmental impacts, and IQ in particular, are among the most consistently observed outcomes, and additional evidence suggests thyroid disruption as one of several potentially contributing biological pathways (Costa et al. 2014; Gibson et al. 2018; Lam et al.…”

Dietary Intake of Endocrine Disrupting Substances Presents in Environment and Their Impact on Thyroid Function

“…They are used as flame retardants, also in wire insulation and cars [ 119 ]. They get into the human body through the respiratory and digestive tract, and they also cross the blood-placenta barrier ( Figure 5 ) [ 120 , 121 , 122 , 123 ].…”