Serum Polybrominated Diphenyl Ether (PBDE) Levels Are Higher in Children (2–5 Years of Age) than in Infants and Adults

BACKGROUND Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in many products and have been detected in human samples worldwide. Limited data show that concentrations are elevated in young children. OBJECTIVES We investigated the association between PBDEs and age with an emphasis on young children from Australia in 2006-2007. METHODS We collected human blood serum samples (n = 2,420), which we stratified by age and sex and pooled for analysis of PBDEs. RESULTS The sum of BDE-47, -99, -100, and -153 concentrations ( summation operator(4)PBDE) increased from 0-0.5 years (mean +/- SD, 14 +/- 3.4 ng/g lipid) to peak at 2.6-3 years (51 +/- 36 ng/g lipid; p < 0.001) and then decreased until 31-45 years (9.9 +/- 1.6 ng/g lipid). We observed no further significant decrease among ages 31-45, 45-60 (p = 0.964), or > 60 years (p = 0.894). The mean summation operator(4)PBDE concentration in cord blood (24 +/- 14 ng/g lipid) did not differ significantly from that in adult serum at ages 15-30 (p = 0.198) or 31-45 years (p = 0.140). We found no temporal trend when we compared the present results with Australian PBDE data from 2002-2005. PBDE concentrations were higher in males than in females; however, this difference reached statistical significance only for BDE-153 (p = 0.05). CONCLUSIONS The observed peak concentration at 2.6-3 years of age is later than the period when breast-feeding is typically ceased. This suggests that in addition to the exposure via human milk, young children have higher exposure to these chemicals and/or a lower capacity to eliminate them.