Table 3.

Annual percent change^a of PCB grouping and specific congeners, p,p′-DDE, and HCB between studies.

	All individuals						Individuals with decreased levels only
	n	Mean	Median	SD	Min	Max	n	Mean	Median	SD	Min	Max
Annual percent change
Σ16PCB50%b	151	6.8	7.8	13.24	−84.3	51.7	128	10.3	9.4	7.28	0.1	51.7
Σ8PerPCBsc	151	3.4	5.8	15.02	−105.5	49.0	114	8.9	8.3	6.74	0.3	49.0
Σ6NONPerPCBsd	151	10.5	11.1	14.91	−81.4	55.3	137	13.5	12.6	8.90	0.3	55.3
p,p′-DDE	151	1.0	3.2	10.96	−35.6	24.2	99	7.0	5.7	5.26	0.4	24.2
HCB	151	−1.7	2.0	14.68	−90.4	21.8	84	7.1	6.4	4.56	0.5	21.8
PCB IUPAC#
105	151	1.1	8.9	30.40	−187.1	60.9	102	16.3	14.6	10.90	0.7	60.9
118	151	5.2	9.3	22.70	−195.4	54.4	117	12.5	12.2	7.91	1.2	54.4
138 [+163+164]e	151	−3.6	3.8	26.67	−145.3	47.4	97	9.5	9.2	7.04	0.4	47.4
153	151	0.9	5.9	21.10	−151.3	48.9	106	9.8	9.4	6.73	0.3	48.9

^a $\mathit{Annual}\mathit{percent}\mathit{change}=\frac{(\mathit{MAWBs}\mathit{level}-\mathit{YAWBs}\mathit{level})/\mathit{MAWBs}\mathit{level}}{\mathit{time}\mathit{interval}\mathit{between}\mathit{blood}\mathit{draws}in\mathit{years}}\times 100$

^bCongeners with ≥ 50% detection rate in MAWBs;IUPAC #s: 52, 70, 74, 84, 87, 95, 99, 101[+90], 105, 110, 118, 149[+123], 138[+163+164], 153, 180, 187.

^cSum of IUPAC#s: 74, 99, 105, 118, 138[+163+164], 153, 180, 187

^dSum of IUPAC#s: 52,84,95,101,110,123[+149].

^eBracket indicates ‘minor’ congener based on aroclor concentration (Hansen, 1999).