Prenatal and postnatal polybrominated diphenyl ether exposure and visual spatial abilities in children

Abstract

Polybrominated diphenyl ethers (PBDEs) are associated with impaired visual spatial abilities in toxicological studies, but no epidemiologic study has investigated PBDEs and visual spatial abilities in children. The Health Outcomes and Measures of the Environment Study, a prospective birth cohort (2003-2006, Cincinnati, OH), was used to examine prenatal and childhood PBDEs and visual spatial abilities in 199 children. PBDEs were measured at 16±3 weeks gestation and at 1, 2, 3, 5, and 8 years using gas chromatography/isotope dilution high-resolution mass spectrometry. We used the Virtual Morris Water Maze to measure visual spatial abilities at 8 years. In covariate-adjusted models, 10-fold increases in BDE-47, -99, and -100 at 5 years were associated with shorter completion times by 5.2s (95% Confidence Interval [CI] -9.3, -1.1), 4.5s (95% CI -8.1, -0.9), and 4.7s (95% CI -9.0, -0.3), respectively. However, children with higher BDE-153 at 3 years had longer completion times (β=5.4s, 95% CI -0.3, 11.1). Prenatal PBDEs were associated with improved visual spatial memory retention, with children spending a higher percentage of their search path in the correct quadrant. Child sex modified some associations between PBDEs and visual spatial learning. Longer path lengths were observed among males with increased BDE-47 at 2 and 3 years, while females had shorter paths. In conclusion, prenatal and postnatal BDE-28, -47, -99, and -100 at 5 and 8 years were associated with improved visual spatial abilities, whereas a pattern of impairments in visual spatial learning was noted with early childhood BDE-153 concentrations.

Keywords: Polybrominated diphenyl ether (PBDE); Virtual Morris Water Maze; Visual spatial learning, visual spatial memory retention, neurodevelopment.

Conflict of interest statement

The authors declare they have no competing financial interests.

Copyright © 2016 Elsevier Inc. All rights reserved.

Figures

Figure 1

Serum concentrations of prenatal and postnatal polybrominated diphenyl ethers, HOME Study. Upper and lower lines of the body of the boxplot represent the 25th and 75th percentile, respectively. Median values are indicated by horizontal lines within boxes and solid squares represent geometric means.

Figure 2

Estimated mean differences and 95% confidence intervals in distance (pool units) for blocks 1–4 in the VMWM by a 10-fold increase in prenatal and postnatal PBDE concentrations, HOME Study. Adjusted by maternal age, race, education, income, maternal serum cotinine, marital status, maternal IQ, child sex, and Home Observation for Measurement of the Environment score. Lower distances indicate better performance on the VMWM maze.

Figure 3

Estimated mean differences and 95% confidence intervals in time (seconds) for blocks 1–4 in the VMWM by a 10-fold increase in prenatal and postnatal PBDE concentrations, HOME Study. Adjusted by maternal age, race, education, income, maternal serum cotinine, marital status, maternal IQ, child sex, and Home Observation for Measurement of the Environment score. Lower times indicate better performance on the VMWM maze.

Figure 4

Estimated mean differences and 95% confidence intervals in distance (%) spent in the correct quadrant during the probe trial by a 10-fold increase in prenatal and postnatal PBDE concentrations, HOME Study. Adjusted by maternal age, race, education, income, maternal serum cotinine, marital status, maternal IQ, child sex, and Home Observation for Measurement of the Environment score. Higher distance percentages indicate better performance on the VMWM probe trial.

Figure 5

Estimated mean differences and 95% confidence intervals in time (seconds) spent in the correct quadrant during the probe trial by a 10-fold increase in prenatal and postnatal PBDE concentrations, HOME Study. Adjusted by maternal age, race, education, income, maternal serum cotinine, marital status, maternal IQ, child sex, and Home Observation for Measurement of the Environment score. Higher times indicate better performance on the VMWM probe trial.