Prenatal exposure to organohalogens, including brominated flame retardants, influences motor, cognitive, and behavioral performance at school age.
BACKGROUND
Organohalogen compounds (OHCs) are known to have neurotoxic effects on the developing brain.


OBJECTIVE
We investigated the influence of prenatal exposure to OHCs, including brominated flame retardants, on motor, cognitive, and behavioral outcome in healthy children of school age.


METHODS
This study was part of the prospective Groningen infant COMPARE (Comparison of Exposure-Effect Pathways to Improve the Assessment of Human Health Risks of Complex Environmental Mixtures of Organohalogens) study. It included 62 children in whose mothers the following compounds had been determined in the 35th week of pregnancy: 2,2'-bis-(4 chlorophenyl)-1,1'-dichloroethene, pentachlorophenol (PCP), polychlorinated biphenyl congener 153 (PCB-153), 4-hydroxy-2,3,3',4',5-pentachlorobiphenyl (4OH-CB-107), 4OH-CB-146, 4OH-CB-187, 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), BDE-99, BDE-100, BDE-153, BDE-154, and hexabromocyclododecane. Thyroid hormones were determined in umbilical cord blood. When the children were 5-6 years of age, we assessed their neuropsychological functioning: motor performance (coordination, fine motor skills), cognition (intelligence, visual perception, visuomotor integration, inhibitory control, verbal memory, and attention), and behavior.


RESULTS
Brominated flame retardants correlated with worse fine manipulative abilities, worse attention, better coordination, better visual perception, and better behavior. Chlorinated OHCs correlated with less choreiform dyskinesia. Hydroxylated polychlorinated biphenyls correlated with worse fine manipulative abilities, better attention, and better visual perception. The wood protective agent (PCP) correlated with worse coordination, less sensory integrity, worse attention, and worse visuomotor integration.


CONCLUSIONS
Our results demonstrate for the first time that transplacental transfer of polybrominated flame retardants is associated with the development of children at school age. Because of the widespread use of these compounds, especially in the United States, where concentrations in the environment are four times higher than in Europe, these results cause serious concern.
Roze
Elise
E
Division of Neonatology, Beatrix Children's Hospital, University Medical Center Groningen, the Netherlands. e.roze@bkk.umcg.nl
Meijer
Lisethe
L
Bakker
Attie
A
Van Braeckel
Koenraad N J A
KN
Sauer
Pieter J J
PJ
Bos
Arend F
AF
D000328:Adult; D002648:Child; D002652:Child Behavior / Q000187:drug effects*; D002675:Child, Preschool; D003071:Cognition / Q000187:drug effects*; D015331:Cohort Studies; D005260:Female; D005333:Fetus / Q000187:drug effects*; D005411:Flame Retardants / Q000633:toxicity*; D055768:Halogenated Diphenyl Ethers / Q000633:toxicity*; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D011075:Polybrominated Biphenyls / Q000633:toxicity*; D011078:Polychlorinated Biphenyls / Q000633:toxicity*; D011247:Pregnancy; D011446:Prospective Studies; D013963:Thyroid Hormones / Q000097:blood
D005411:Flame Retardants; D055768:Halogenated Diphenyl Ethers; D011075:Polybrominated Biphenyls; D013963:Thyroid Hormones; D011078:Polychlorinated Biphenyls