Air Quality Criteria for Lead Volume II of II - (NEPIS)(EPA) - US ...

AX6-232
Table AX6-9.3 (cont’d.). Effects of Lead on Hematopoietic System in Children
Reference, Study
Location, and Period Study Description Pb Measurement Findings, Interpretation
Europe
Graziano et al. (2004)
(Factor Litvak et al.
(1999, 1998)
Yugoslavia
1985–1998
Design: prospective
Subjects: children (n = 311; age range
4.5–12 yr) from high-Pb (smelter/refinery)
and low-Pb areas
Outcome measures: blood Hgb, serum EPO.
Analysis: multivariate linear regression
(GEE for repeated measures)
Blood Pb (µg/dL) range:
4.5 yr: 4.6–73.1
6.5 yr: 3.1–71.7
9.0 yr: 2.3–58.1
Blood Pb (µg/dL) means
for ages 4.5–12 yrs:
High Pb: 30.6–39.3
Low Pb: 6.1–9.0
Significant association between increasing blood Pb concentration
and increasing serum EPO concentration at ages 4.5 (p < 0.0001)
and 6.5 yr (p < 0.0007), with decreasing regression slope with age:
4.5 yr: ∃ = 0.21 (SE 0.043), p = 0.0001; 6.5 yr: ∃ = 0.11 (SE 0.41),
p = 0.0103; 9.5 yr: ∃ = 0.029 (SE 0.033), p = 0.39; 12 yr: ∃ = 0.016
(SE 0.031), p = 0.60.
Covariates retained in regression model were age (∀), blood Pb (∃),
and blood Hgb ((). GEE for repeated measures yielded (Factor-
Litvak et al., 1998, updated from personal communication from
Graziano 07/2005):
(: 0.6097 (95% CI: −0.0915, −0.0479), p < 0.0001
4.5 yr: ∀ = 1.3421 (95% CI: 1.0348, 1.6194), p < 0.0001
∃ = 0.2142 (95% CI: 0.1282, 0.3003), p < 0.0001
6.5 yr: ∀ = 1.6620 (95% CI: 1.3737, 1.9503), p < 0.0001
∃ = 0.1167 (95% CI: 0.0326, 0.2008), p < 0.001
9.5 yr: ∀ = 1.7639 (95% CI: 1.4586, 2.0691), p < 0.0001
∃ = 0.0326 (95% CI: −0.0346, 0.0998), p = 0.1645
12 yr: ∀ = 1.8223 (95% CI: 1.524, 2.1121), p < 0.0001
∃ = 0.0112 (95% CI: −0.0359, 0.0584), p = 0.1645
Based on the GEE, the predicted increase in serum EPO per 10
µg/dL increase in blood Pb concentration (at Hgb = 13 g/dL) \ was:
1.25 mIU/mL (36%) at age 4.5 yr and 1.18 (18%) at age 6.5 yr.
Blood Hgb levels were not significantly different in children from
high-Pb area (mean 25–38 µg/dL) compared to low-Pb area (mean
5–9 µg/dL).