Table 2.
Selected percentiles of tOP concentrations [μg/L (95% CI)] in urine for the U.S. population ≥ 6 years of age.a
| Variable | 10th percentile | 25th percentile | 50th percentile | 75th percentile | 90th percentile | 95th percentile | No. |
|---|---|---|---|---|---|---|---|
| All | < LOD | < LOD | 0.3 (< LOD–0.4) | 0.9 (0.5–1.2) | 1.6 (1.1–2.2) | 2.2 (1.6–3.2) | 2,517 |
| < LOD | < LOD | 0.3 (< LOD–0.5) | 0.9 (0.6–1.3) | 1.9 (1.3–2.5) | 2.8 (2.0–4.0) | 2,514 | |
| 6–11 years | < LOD | < LOD | 0.4 (0.2–0.5) | 0.8 (0.5–1.4) | 1.6 (1.1–2.1) | 2.0 (1.5–2.9) | 314 |
| < LOD | < LOD | 0.5 (0.3–0.6) | 1.1 (0.7–1.6) | 2.0 (1.7–2.2) | 2.4 (2.0–6.0) | 314 | |
| 12–19 years | < LOD | < LOD | 0.4 (0.2–0.5) | 1.1 (0.6–1.5) | 1.7 (1.2–2.4) | 2.4 (1.6–3.2) | 715 |
| < LOD | < LOD | 0.3 (0.2–0.5) | 0.7 (0.5–1.2) | 1.6 (1.1–2.6) | 2.6 (1.5–3.7) | 713 | |
| 20–59 years | < LOD | < LOD | 0.2 (< LOD–0.4) | 0.7 (0.5–1.2) | 1.7 (1.1–2.3) | 2.2 (1.5–3.4) | 951 |
| < LOD | < LOD | 0.3 (< LOD–0.4) | 0.8 (0.5–1.1) | 1.6 (1.1–2.7) | 2.7 (1.6–3.7) | 950 | |
| 60 years | < LOD | < LOD | 0.3 (< LOD–0.4) | 1.0 (0.7–1.4) | 1.7 (1.1–2.2) | 2.4 (1.6–2.9) | 537 |
| < LOD | < LOD | 0.4 (< LOD–0.7) | 1.2 (0.8–1.7) | 2.4 (1.7–3.2) | 3.3 (2.3–5.3) | 537 | |
| Female | < LOD | < LOD | 0.2 (< LOD–0.4) | 0.9 (0.5–1.2) | 1.6 (1.1–2.3) | 2.3 (1.5–2.9) | 1,288 |
| < LOD | < LOD | 0.4 (< LOD–0.6) | 1.0 (0.6–1.4) | 2.2 (1.4–3.0) | 3.3 (2.4–4.8) | 1,286 | |
| Male | < LOD | < LOD | 0.3 (< LOD–0.4) | 0.9 (0.5–1.5) | 1.8 (1.2–2.4) | 2.2 (1.6–3.2) | 1,229 |
| < LOD | < LOD | 0.3 (< LOD–0.4) | 0.7 (0.5–1.1) | 1.6 (1.1–2.3) | 2.4 (1.6–3.3) | 1,228 | |
| Mexican American | < LOD | < LOD | < LOD | 0.5 (0.3–0.6) | 0.8 (0.6–1.3) | 1.3 (0.8–1.8) | 613 |
| < LOD | < LOD | < LOD | 0.4 (0.3–0.6) | 0.9 (0.6–1.4) | 1.6 (0.9–2.7) | 612 | |
| Non-Hispanic black | < LOD | < LOD | 0.4 (< LOD–0.5) | 1.0 (0.7–1.4) | 1.9 (1.3–2.6) | 2.4 (1.6–3.1) | 652 |
| < LOD | < LOD | 0.3 (< LOD–0.4) | 0.8 (0.5–1.1) | 1.5 (1.1–2.1) | 2.3 (1.7–2.8) | 651 | |
| Non-Hispanic white | < LOD | < LOD | 0.3 (< LOD–0.5) | 0.9 (0.6–1.5) | 1.7 (1.2–2.4) | 2.3 (1.6–3.3) | 1,092 |
| < LOD | < LOD | 0.4 (< LOD–0.6) | 1.0 (0.6–1.4) | 2.0 (1.4–3.0) | 3.1 (2.2–4.2) | 1,091 |
CI, confidence interval. Data are from NHANES 2003–2004. Blue lines denote measure in μg/g creatinine.
a
The geometric mean was not calculated because the overall weighted frequency of detection was < 60% (57.4%). Persons not defined by these three race/ethnicity groups were included only in the total population estimate. LOD = 0.2 μg/L.