Table 4.

Geometric mean and selected percentiles (95% confidence intervals) of perfluorohaxanesulfonate (PFHxS) concentrations in serum (μg/L) for the U.S. population 12 years of age and older: data from NHANES 2003–2004.

Variable	Geometric mean	10th percentile	25th percentile	50th percentile	75th percentile	90th percentile	95th percentile	No.
All	1.9 (1.7–2.2)	0.7 (0.6–0.7)	1.0 (0.9–1.2)	1.9 (1.6–2.1)	3.3 (2.8–3.9)	5.9 (4.8–7.2)	8.3 (7.1–9.7)	2,094
12–19 years	2.4 (2.1–2.9)	0.6 (0.5–0.8)	1.2 (1.0–1.4)	2.3 (1.7–3.0)	4.8 (3.9–6.0)	9.5 (6.8–12.5)	13.1 (9.9–19.6)	640
20–39 years	1.8 (1.6–2.0)	0.5 (0.5–0.6)	1.0 (0.9–1.2)	1.7 (1.5–2.0)	2.8 (2.5–3.3)	4.8 (3.9–6.1)	6.7 (4.9–9.4)	490
40–59 years	1.9 (1.6–2.2)	0.7 (0.5–0.8)	1.0 (0.9–1.2)	1.6 (1.4–2.0)	3.1 (2.3–4.5)	5.5 (4.3–6.9)	6.7 (5.5–8.2)	387
≥ 60 years	2.0 (1.7–2.4)	0.8 (0.5–0.9)	1.1 (1.0–1.3)	1.9 (1.6–2.1)	3.2 (2.6–3.7)	7.2 (4.3–9.7)	10.2 (7.0–12.6)	577
Mexican American	1.4 (1.2–1.7)	0.5 (0.3–0.7)	0.7 (0.5–0.9)	1.4 (1.2–1.7)	2.3 (1.9–2.7)	4.2 (3.1–5.1)	5.4 (4.0–8.9)	485
Non-Hispanic black	1.9 (1.6–2.3)	0.5 (0.3–0.7)	1.1 (0.9–1.3)	1.9 (1.5–2.2)	3.4 (2.7–4.3)	6.0 (5.0–7.1)	8.2 (6.3–12.0)	538
Non-Hispanic white	2.0 (1.8–2.3)	0.7 (0.6–0.8)	1.1 (1.0–1.3)	1.9 (1.6–2.1)	3.3 (2.8–4.0)	6.0 (4.6–7.8)	8.1 (6.9–10.1)	962
Female	1.7 (1.6–1.9)	0.6 (0.5–0.6)	0.9 (0.8–1.0)	1.5 (1.4–1.8)	2.9 (2.5–3.5)	5.8 (4.6–6.9)	8.2 (6.7–10.0)	1,041
Male	2.2 (1.9–2.5)	0.8 (0.7–1.0)	1.3 (1.1–1.4)	2.0 (1.8–2.4)	3.3 (2.8–4.4)	6.1 (4.6–8.1)	8.5 (6.4–10.5)	1,053