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

AX6-79
Table AX6-4.1 (cont’d). Renal Effects of Lead in the General Population
Reference, Study
Location, and
Period Study Description Pb Measurement Findings, Interpretation
Asia
Lin et al. (1993)
Taiwan
Study date not
provided
Satarug et al. (2004)
Bangkok, Thailand
Study date not
provided
123 adults living near a Pb battery factory for more
than 10 yrs.
Divided into 3 groups by proximity to the factory.
Group 1 ≤500 m (n = 49)
Group 2 1000-1500 m (n = 47)
Group 3 farther away (n = 27)
Exclusionary criteria included history of exposure to
nephrotoxicants and nephrotoxicant medications, such
as NSAIDs.
24 h urinary NAG excretion
3.3 U/day (Group 1)
2.4 U/day (Group 3)
Multiple linear regression with adjustment for age.
118 Thai adults (53 men, 65 women).
Renal outcome measures noted below, also include
BUN and total urinary protein.
Serum creatinine
0.94 mg/dL (males)
0.66 mg/dL (females)
Urinary NAG
4.4 U/g creatinine (males)
4.6 U/g creatinine (females)
Urinary ∃ 2-microglobulin
51 µg/g creatinine (males)
29 µg/g creatinine (females)
Mean blood Pb
16.6 µg/dL (Group 1)
13.5 µg/dL (Group 2)
7.9 µg/dL (Group 3)
EDTA diagnostic chelation
(done in Group 1)
126.1 µg/24 hrs
Mean “serum” Pb
0.42 µg/dL (males) 0.3 µg/dL
(females)
Note – cannot determine from
article if actually serum Pb
(much less commonly used) or
blood Pb.
Mean urinary Pb
1.3 µg/g creatinine (males)
2.4 µg/g creatinine
(females)
Urinary cadmium also
assessed.
Significantly higher prevalence of abnormal urinary NAG
found in the exposed group 1 compared to the control group 3
(55.6% compared to 11.1%; p < 0.001). However, mean
NAG not significantly higher in Group 1.
In all 45 participants in whom both measures were obtained,
EDTA chelatable Pb was not correlated with urinary NAG
excretion. However, a significant correlation between EDTA
chelatable Pb #200 µg/24 hrs and urinary NAG excretion was
observed in the 39 participants in this group. Further
evaluation with multiple linear regression, adjusting for age,
revealed a ∃ = 0.034 (95% CI: 0.009, 0.059); p = 0.01.
No correlation noted between blood Pb level and urinary
NAG.
Limitations = small sample size, plots indicate potential for
influential outliers.
In men, urinary Pb excretion correlated only with urinary
protein at borderline significance (r = 0.22, p < 0.06).
In women, urinary Pb excretion correlated with urinary NAG
(r = 0.5, p < 0.001), protein (r = 0.31, p = 0.01) and
∃ 2-microglobulin (r = 0.36, p = 0.002) excretion.
After adjustment for urinary cadmium, only association
between urinary Pb and NAG remained significant.
Three urinary renal biomarkers correlated with urinary
cadmium, although only at borderline significance (p = 0.06)
for ∃2-microglobulin.
Limitations = small sample size, Pb dose assessment since
only urine Pb used in renal analyses, limited data analysis.