Stapleton et al. of the women in the study were non-Hispanic higher than normal, whereas the remaining of HBCD (alpha, beta, and gamma), 246 TBP, black, and 23% were < 20 years of age. Note 37% were within normal ranges. and four different hydroxylated PBDE conge- that oversampling of non-Hispanic blacks PBDEs. PBDE data are available for 137 of ners by liquid chromatography tandem mass is an intentional component of the parent the 140 women enrolled (Table 2). Eight of the spectrometry. HBCD was < 0.17 ng/g lipid HPHB Study. This was the first pregnancy 27 PBDE congeners measured were found to in all serum extracts; however, α-HBCD was for roughly half of the women enrolled in this be above MDLs in the serum samples analyzed. detected (0.18–0.21 ng/g lipid) in the stan- study, and more than 87% completed high Attempts were made to measure BDE-209; dard reference material (SRM 1958; National school. Of all the women participating in this however, laboratory blank contamination with Institute of Standards and Technology, study, only one reported a personal history BDE-209 resulted in all values below the MDL. Gaithersburg, MD) used for quality assur- with thyroid problems; she was not excluded Total PBDEs (defined as the sum of BDEs 47, ance/quality control, demonstrating that the from this study. 99, 100, and 153) were log-normally distrib- method did recover HBCD. The measured hTyroid hormones. Thyroid hormone data uted; however, individual PBDEs were not nor- concentration in SRM 1958 ranged from 64 to were available for only 137 of the 140 women mal or log-normally distributed. At least one of 76% of the reported value (Keller et al. 2010). enrolled (Table 2); however, we had a total the BDE congeners was detected in all samples, 6´-OH-BDE-49 and 6-OH-BDE-99 were not of 136 thyroid hormone measurements per and total PBDE concentrations ranged from detected in any samples (MDL = 0.035 ng/g individual hormone type because of problems 3.6 to 694 ng/g lipid (Table 2). lipid). 4´-OH-BDE-49 and 6-OH-BDE-47 with the laboratory measurement of some hor- T h e m o s t a b u n d a n t c o n g e n e r w a s were detected in 72% and 67% of the sam- mones in a few samples. TSH, FT4, and FT3 2,2´,4,4´-tetrabromodiphenyl ether (BDE-47), ples, respectively. 246 TBP was detected at the were log-normally distributed, whereas TT4 which ranged in concentration from < 2.0 to highest concentrations (< 1.4–151 ng/g lipid); was normally distributed. TT3 was not nor- 297 ng/g lipid, with a geometric mean value however, values were above MDL in only mal or log-normally distributed and was log- of 16.5 ng/g lipid. BDE-47 contributed 50% 38% of the samples. Total OH-BDE levels transformed for regression analysis. With the of the total PBDE burden, on average. The (4´-OH-BDE-49 plus 6-OH-BDE-47) ranged exception of one participant with a TSH level second most abundant BDE congener was from < 0.03 to 13.3 ng/g lipid, with a geomet- of 0.31 µIU/mL, all serum samples were found 2,2´,4,4´,5,5´-hexabromodiphenyl ether ric mean value of 0.28 ng/g lipid. to have TSH levels within normal ranges. (BDE-153) and the most commonly detected Associations between PBDEs, metabolites, Pregnancy can affect thyroid hormone levels, (~ 96% of samples), with concentrations rang- and thyroid hormones. The PBDEs were all and normal ranges presented here are for the ing from < 1.2 to 67.6 ng/g lipid. BDE-153 highly correlated (r = 0.39–0.95) (Table 3). general population. Approximately 10% of the was approximately 20% of the total PBDE Total PBDEs and individual BDE congeners serum samples (n = 13) had FT4 levels below burden, on average, although in one indi- were highly correlated with 4´-OH-BDE-49 normal ranges, and one was just above normal vidual serum sample BDE-153 was the only (r = 0.38–0.62; Figure 1) and 6-OH-BDE-47 at 1.22 ng/dL. For measurement of TT4, 28% congener detected. On average, 2,2´,4,4´,5- (r = 0.29–0.40). 4´-OH-BDE-49 and 6-OH- of the serum samples had levels below the nor- p e n t a b r o m o d i p h e n y l e t h e r ( B D E - 9 9 ) BDE-47 were also highly correlated (r = 0.62, mal range, and five samples had TT4 levels and 2,2´,4,4´,6-pentabromodiphenyl ether p < 0.0001). above normal. Five samples had FT3 levels (BDE-100) represented 17% and 14% of the None of the correlations between TSH below the normal range, and two were higher total PBDE burden, respectively. and PBDEs were significant (Table 3). TT4 than normal. In contrast, approximately 63% HBCD and phenolic metabolites. A subset was correlated with most of the PBDEs (r = of the serum samples displayed TT3 levels of 57 samples was further analyzed for isomers 0.18–0.21 and p < 0.05 for BDEs 47, 100, Table 2. Thyroid hormone levels and PBDE and metabolite concentrations (nanograms per gram lipid) measured in serum from pregnant women. Percentile Detection Geometric mean Variable MDL frequency (%) (95% CI) Min Max 25th 50th 75th 95th Thyroid hormones (n = 136) TSH (µIU/mL) 100.00 1.25 (1.15–1.37) 0.31 5.38 0.89 1.28 1.76 2.91 TT4 (µg/dL) 98.53 6.1 (5.4–6.7) 0.3 11.9 5.2 6.9 8.5 10.4 FT4 (ng/dL) 100.00 0.67 (0.64–0.69) 0.40 1.22 0.59 0.67 0.75 0.89 TT3 (ng/dL) 100.00 195 (186–204) 100 411 165 188 221 349 FT3 (pg/mL) 100.00 2.71 (2.65–2.77) 1.85 4.25 2.47 2.71 2.97 3.39 PBDEs (n = 137) BDE-28 1.2–3.0 38.69 < 1.2 16.89 0.60 0.60 2.58 6.00 BDE-47 2.0–4.5 94.89 16.5 (13.64–19.98) < 2.0 297.45 8.98 18.87 30.64 114.36 BDE-66 1.2 2.19 < 1.2 3.93 0.60 0.60 0.60 0.60 BDE-99 2.0–4.5 64.23 4.72 (3.74–5.94) < 2.0 249.08 1.00 5.50 12.59 49.83 BDE-100 1.2 89.05 4.19 (3.51–5.00) < 1.2 107.45 2.27 4.61 7.20 25.85 BDE-85, -155 1.2 16.06 < 1.2 10.49 0.60 0.60 0.60 4.58 BDE-153 1.2 96.35 5.93 (5.09–6.92) < 1.2 67.55 3.82 5.65 9.82 32.33 BDE-154 1.2 48.18 < 1.2 52.89 0.60 0.60 2.40 7.59 ∑PBDEsa 3.59 693.95 20.02 36.56 64.58 228.16 Phenolic metabolites (n = 57)b 246 TBP 1.4–2.5 38.18 < 1.4 150.74 1.65 2.43 15.14 119.71 4’-OH-BDE-49 0.01–0.03 71.93 0.11 (0.07–0.16) < 0.01 3.92 0.02 0.12 0.27 2.32 6-OH-BDE-47 0.01–0.03 66.67 0.17 (0.10–0.29) < 0.01 10.79 0.02 0.19 0.57 5.82 ∑OH-BDEsc < 0.03 13.28 0.10 0.33 0.96 6.99 Abbreviations: Max, maximum; Min, minimum; NA, not available (detection frequency was < 50%). a∑PBDEs variable includes BDE‑47, BDE‑99, BDE‑100, and BDE‑153 because each of these had > 50% detection rates. In creating this summed variable of the four PBDEs, observa‑ tions that were below detection limit were included as one‑half MDL. bFor 246 TBP, total n = 55. c∑OH‑BDEs includes 4´‑OH‑BDE‑49 and 6‑OH‑BDE‑47 because each of these had > 50% detection rates. 1456 119 | number 10 | October 2011 • Environmental Health Perspectives ovlume