Twenty-three workers who had occupationally been exposed to lead were ex-amined for blood and urinary lead contents (bPb, uPb), urinary delta-aminolevulinic acid and coproporphyrin contents (δ-ALA, Copro), erythrocyte δ-ALA dehydratase activities (ALA-D), hemoglobin concentration (Hb), and 2-hr and 24-hr urinary lead excretions since the start of 1-hr intravenous infusion of 20 mg CaEDTA per kilo-gram of body weight (uPb
2-hr mob., uPb
24-hr mob.). The blood lead value (μg/100g) ranged from 4 to 73 with an average of 24.
By factor analysis, the parameters were classified to three groups. The first group consisted of uPb
24-hr mob., uPh
2-hr mob., bPb, uPb and ALA-D; the second group, δ-ALA and Copro; and the third group, Hb.
There were found highly significant linear relationships between all pairs of bPb, uPb, ALA-D, uPb
2-hr mob, and uPb
24-hr mob, on a log scale. Δ-ALA, Copro and Hb had less in extent, but significant correlations with five parameters mentioned above. BPb, uPb, Hb and uPb
2-hr mob. had the closest correlations with uPb
24-hr mob.;ALA-D, with bPb; and δ-ALA, Copro.
The criteria for the mobilization yield were estimated from the viewpoint of acceptable limit in lead absorption.
Practical usefulness of "2-hr method (uPb
2-hr mob.)" was indicated as a simplified diagnostic mobilization test.
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