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

AX6-97
Table AX6-4.2 (cont’d). Renal Effects of Lead in the Occupational Population
Reference, Study
Location, and
Period Study Description Pb Measurement Findings, Interpretation
Asia (cont’d)
Weaver et al. (2003a)
South Korea
1997-1999
803 Pb workers including 164 females and 94 former Pb
workers.
Serum creatinine
0.90 mg/dL
Calculated creatinine clearance
94.7 mL/min
4-hr measured creatinine clearance
114.7 mL/min
RBP
63.6 µg/g creatinine
NAG
215.3 μmol/h/g creatinine
Multiple linear regression, adjusting for age, gender, BMI,
work status (current vs. former worker), HTN or blood
pressure (depending on model), and, for the EBE markers,
alcohol ingestion and diabetes.
42 associations modeled (7 Pb measures with 6 renal
outcomes).
Interaction models that assessed effect modification by
age in tertiles in 24 associations (4 Pb exposure/dose
measures with 6 renal outcomes).
Mean blood Pb
32.0 µg/dL
Mean tibia Pb
37.2 μg/g bone mineral
Mean DMSA-chelatable Pb
767.8 μg/g creatinine
Pb exposure also assessed
with job duration and three
hematologic measures as
surrogates for Pb dose
(aminolevulinic acid in
plasma, zinc protoporphyrin,
and hemoglobin).
Mean urinary cadmium
measured in
subset (n = 191)
1.1 µg/g creatinine
After adjustment, higher Pb measures associated with
worse renal function in 9 of 42 models.
Associations in the opposite direction (higher Pb
measures associated with lower serum creatinine and
higher creatinine clearances) in five models.
Opposite direction (inverse) associations observed only
in models of the clinical outcomes whereas the
associations between higher Pb dose and worse renal
function were predominantly among the biomarker
models.
In three of 16 clinical renal interaction models, positive
associations between higher Pb measures and worse
renal function in participants in the oldest age tertile
were significantly different from associations in those
in the youngest age tertile which were in the opposite
direction.
- This pattern was observed at borderline significance
(p < 0.1) in 3 other models.
- Pattern was not observed in the EBE marker models.
Urinary cadmium associated with NAG.
Authors concluded that occupational Pb exposure in
the moderate dose range has an adverse effect on renal
function. Inverse associations may represent
hyperfiltration. Environmental cadmium may have an
adverse impact, at least on NAG.