Table 2.

Distribution of serum PBB, PCB and PBDE congeners (ng/mL) among the Michigan PBB Registry participants.

Chemical (ng/mL)	N	%>LOD	P25	P50	P75	P95	Max	GM^a (95% CI)
Polybrominated biphenyl
PBB-77	861	7.4%	<LOD	<LOD	<LOD	0.01	0.34	-
PBB-101	861	7.9%	<LOD	<LOD	<LOD	0.01	0.60	-
PBB-153	861	92%	0.06	0.26	0.63	3.9	236	0.17 (0.14, 0.10)
PBB-180	861	0.4%	<LOD	<LOD	<LOD	<LOD	0.31	-
Polychlorinated biphenyl
PCB-118	832	100%	0.03	0.06	0.11	0.29	0.89	0.06 (0.05, 0.06)
PCB-138	861	100%	0.09	0.21	0.40	1.1	3.3	0.20 (0.18, 0.21)
PCB-153	861	100%	0.11	0.25	0.45	1.1	2.7	0.22 (0.20, 0.23)
PCB-180	861	100%	0.08	0.19	0.34	0.75	4.9	0.16 (0.14, 0.17)
ΣPCB₄^b	832	-	0.34	0.74	1.3	3.1	8.1	0.64 (0.60, 0.69)
ΣPCB₄ (pmol/mL) ^b,c	832	-	0.91	2.0	3.6	8.6	22	1.8 (1.7, 1.9)
ΣPCB₃^b	861	-	0.30	0.67	1.2	3.0	7.6	0.58 (0.54, 0.62)
ΣPCB₃ (pmol/mL) ^b,c	861	-	0.80	1.8	3.2	8.0	21	1.6 (1.5, 1.7)
Polybrominated diphenyl ether
PBDE-47	358	92%	0.10	0.21	0.42	1.3	18	0.19 (0.18, 0.21)
PBDE-85	358	2.0%	<LOD	<LOD	<LOD	<LOD	0.16	-
PBDE-99	358	45%	<LOD	<LOD	0.03	0.11	2.9	-
PBDE-100	358	38%	<LOD	<LOD	0.02	0.10	1.6	-
PBDE-153	358	5.3%	<LOD	<LOD	<LOD	0.05	0.51	-
ΣPBDE₃^b	358	-	0.11	0.23	0.49	1.6	23	0.21 (0.19, 0.23)
ΣPBDE₃ (pmol/mL) ^b,c	358	-	0.23	0.45	0.99	3.2	45	0.43 (0.39, 0.47)

Abbreviation: N, sample number; LOD, limit of detection; P25, the 25th percentile; GM, geometric mean; CI, confidence interval.

Geometric means were not calculated for congeners with detection frequencies <60% (For the congeners with detection frequencies ≥60%, the values below LOD were replaced by LOD/√2, and the congeners with detection frequencies <60%, were substituted with zero).

ΣPCB₄ was calculated by adding PCB-118, 138, 153, 180; ΣPCB₃: PCB-138, 153, 180; ΣPBDE₃: PBDE-47, 99, 100.

Sums on the molar basis. Molar sums were calculated by dividing the concentration of each congener by its molecular weight, multiplying by 1,000 to convert nmol/mL to pmol/mL, and then summing the congeners.