Polybrominated diphenyl ethers (PBDEs) and 2,2',4,4',5,5'-hexabromobiphenyl (BB-153)
are chemicals known as brominated flame retardants. We have assessed the exposure
status of the United States population to PBDEs and BB-153 and explored associations
with demographic information, including participants' age, sex, and race/ethnicity.
A total of 2,062 serum samples, from participants in the National Health and Nutrition
Examination Survey (NHANES) 2003-2004 aged 12 years and older, were analyzed for PBDEs
and BB-153; stratified and regression analyses were used to examine levels among demographic
groups. The congener with the highest serum concentration was 2,2',4,4'-tetrabromodiphenyl
ether (BDE-47) [geometric mean 20.5 ng/g lipid]; followed by 2,2',4,4',5,5'-hexaBDE
(BDE-153) [5.7 ng/g lipid]; 2,2',4,4',5-pentaBDE (BDE-99) [5.0 ng/g lipid; a value
equal to the highest limit of detection for an individual sample]; 2,2',4,4',6-pentaBDE
(BDE-100) [3.9 ng/g lipid]; BB-153 [2.3 ng/g lipid]; and 2,4,4'-triBDE (BDE-28) [1.2
ng/g lipid]. For BDE-47, we observed no significant difference in the least-squares
geometric mean (LSGM) by sex, but with age we found both a linear decrease (p = 0.01)
and a positive quadratic trend (p = 0.01). Its LSGM, 27.9 ng/lipid, in the 12-19 year
olds decreased to 17.2 ng/g lipid in the 40-49 year group, and then curved upward
to 20.4 ng/g lipid in the > or =60 years olds. Mexican Americans had the highest LSGM
of BDE-47 (24.5 ng/g lipid), which was significantly higher than that of non-Hispanic
whites (19.7 ng/g lipid, p = 0.01). Adults 60 years and older were twice as likely
as adults 20-59 years old to have a serum BDE-47 concentration above the 95th percentile
(p = 0.02). These data provide needed exposure assessment data for public health decisions.