TABLE 3

Distribution of BLLs According to Selected Demographic Characteristics, Children Aged 1 to 5 Years, NHANES III, Phase 2 (1991–1994)

nGeometric mean (95% CI), μg/dL<1 μg/dL, % (95% CI)1 to <2.5 μg/dL, % (95% CI)2.5 to <5 μg/dL, % (95% CI)5 to <7.5 μg/dL, % (95% CI)7.5 to <10 μg/dL, % (95% CI)≥10 μg/dL, % (95% CI)
Overall23922.7 (2.5–3.0)8.2 (6.4–10.3)37.7 (33.4–42.1)33.1 (29.5–36.8)12.1 (9.1–15.6)4.4 (3.0–6.1)4.4 (2.7–6.5)
Gender
    Girl11812.7 (2.4–2.9)7.1 (5.0–9.4)42.3 (36.2–48.5)31.7 (26.2–37.6)11.5 (8.3–15.3)4.1 (2.4–6.2)3.3 (2.0–4.9)
    Boy12112.8 (2.5–3.1)9.3 (6.6–12.4)33.5 (28.4–38.7)34.3 (28.5–40.5)12.7 (9.4–16.4)4.7 (2.9–6.9)5.5 (3.1–8.4)
Age
    1–2 y9873.1 (2.8–3.5)6.1 (4.1–8.6)30.3 (25.9–34.9)36.9 (31.5–42.5)14.8 (11.8–18.1)6.0 (3.6–8.8)5.9 (3.4–9.0)
    3–5 y14052.5 (2.3–2.7)9.6 (7.4–12.0)42.6 (37.4–47.8)30.6 (27.1–34.2)10.4 (6.9–14.5)3.4 (2.2–4.9)3.4 (2.0–5.3)
Race/ethnicity
    Non-Hispanic black7834.3 (3.7–5.0)1.9 (0.6–4.0)a17.9 (12.3–24.3)38.3 (32.2–44.6)22.0 (15.8–29.0)8.6 (6.0–11.7)11.2 (5.9–18.0)
    Mexican American8273.1 (2.7–3.5)5.7 (3.1–8.9)30.1 (24.8–35.8)41.3 (37.6–45.2)13.6 (10.1–17.4)5.3 (3.3–7.6)4.0 (1.8–6.9)a
    Non-Hispanic white6312.3 (2.1–2.5)10.2 (7.6–13.1)44.7 (39.8–49.7)31.6 (28.2–35.0)8.9 (5.6–12.8)2.4 (0.9–4.7)2.3 (0.8–4.5)a
PIR
    ≤1.312493.7 (3.3–4.2)1.8 (0.7–3.5)a27.2 (20.6–34.4)35.3 (29.6–41.3)19.4 (13.4–26.1)8.3 (5.9–11.1)7.9 (5.0–11.5)
    >1.310012.1 (2.0–2.3)13.2 (10.0–16.8)45.6 (41.7–49.6)31.3 (28.0–34.7)6.7 (4.4–9.6)1.6 (0.7–2.9)a1.5 (0.8–2.6)
Medicaid status
    Yes9843.9 (3.5–4.3)2.0 (0.7–4.0)a23.0 (17.7–28.9)36.5 (28.9–44.4)20.8 (14.7–27.8)9.1 (6.2–12.5)8.5 (4.9–13.0)
    No14032.3 (2.1–2.5)11.0 (8.5–13.9)44.4 (40.0–48.7)31.6 (28.1–35.2)8.2 (6.4–10.1)2.3 (1.3–3.6)2.5 (1.2–4.3)
Year housing built (risk of lead exposure)b
    Low risk7442.0 (1.9–2.2)13.7 (9.6–18.5)49.4 (42.6–56.2)27.7 (23.0–32.6)6.0 (3.9–8.7)1.6 (1.1–2.0)1.6 (0.4–3.8)a
    Medium risk8892.8 (2.6–3.0)6.5 (4.0–9.7)39.0 (31.5–46.8)33.4 (27.4–39.8)13.4 (8.9–18.8)2.9 (1.5–4.9)4.6 (2.6–7.2)
    High risk3683.8 (3.1–4.5)5.4 (1.5–11.6)a20.9 (14.5–28.3)36.3 (27.9–45.2)18.3 (13.0–24.3)10.4 (6.7–15.0)8.6 (4.6–13.6)
    Not known3513.6 (3.0–4.2)1.5 (0.3–3.8)a27.2 (17.7–37.8)40.5 (32.5–48.9)17.0 (10.9–24.2)8.1 (4.0–13.5)5.6 (1.3–12.6)a
  • a Relative SE of point estimate ≥30%; does not meet standard of statistical reliability and precision.

  • b Risk of lead exposure by year housing built defined as follows:

    NHANES 1999–2004: low risk, built 1978 and later; medium risk, built between 1950 and 1977; high risk, built before 1950.

    NHANES III phases 1 and 2: low risk, built 1974 and later; medium risk, built between 1946 and 1973; high risk, built before 1946.