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

AX6-62
Table AX6-3.7 (cont’d). Postural Stability, Autonomic Testing, Electroencephalogram, Hearing Thresholds, and
Occupational Lead Exposure in Adults
Reference, Study
Location, and Period Study Description Pb Measurement Findings, Interpretation
Asia (cont’d)
Niu et al. (2000)
China
44 Pb-exposed workers (17 men, 27 women)
from Pb printing houses, mean age 35 (4.9)
and education 9.3 (no SD) yrs and 34
controls (19 men and 15 women), mean age
33 (7.4) yrs and education 9.5 (no SD) yrs
had autonomic nervous system examined.
ANCOVA controlling for age, sex and
education examined group differences and
linear regression for dose-response
relationship.
Pb workers
Mean (SD) blood Pb 29
(26.5) µg/dL
(8 workers blood Pb
exceeded 50 µg/dL)
Controls
Mean (SD) blood Pb 13
(9.9) µg/dL
(1 control blood Pb
exceeded 50 µg/dL)
Niu et al. (2000) examined autonomic nervous system in 44 Pb
exposed workers, mean blood Pb 29 µg/dL, and 34 controls, mean
blood Pb, 13 µg/dL. Linear regression found association between
blood Pb and decreased R-R interval with valsalva (F/T 2.349,
p < 0.05) and duration of Pb exposure and decreased R-R interval
with deep breathing (F/T 3.263, p < 0.01) after adjusting for age, sex,
education, smoking and drinking. In the same study, quantitative
EEG found significant abnormalities in the Pb-exposed workers,
dominant low amplitude in 59%, dominant beta frequency in 42%
and abnormalities in 81%.