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

AX6-61
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)
Ratzon et al. (2000)
Israel
Teruya et al. (1991)
Japan
Ishida et al. (1996)
Japan
63 Pb battery workers, mean age 39 (8.7) yrs
and 48 controls mean age 36 (11.8) yrs,
matched for age with similar sex and
education, had postural control measured.
Group differences examined with t test.
Dose-effect relations assessed with
Pearson = s correlation coefficients. Linear
regression done with exposure category as
major predictor.
172 Pb exposed workers, mean age 34
(18.4-57.4) yrs had cardiac autonomic
nervous system evaluated by R-R intervals
variation with respiration measured.
128 workers in the ceramic painting industry,
58 men, mean age 55 (11.7) yrs and
70 women, mean age 52 (9.2) yrs had
measures of sympathetic function by
variations in R-R interval on EKG and
changes in finger blood flow with postural
changes using Doppler flowmetry.
Correlation analyses and linear regression
examined relationship of finger blood flow
and Pb exposure after adjusting for
covariates.
Mean past blood Pb
38 µg/dL
Mean yrs employed 11
Cumulative Pb determined
by avg blood Pb Η yrs
employed
Mean (range) blood Pb 36
(5-76) µg/dL
Men
Mean (SD) blood Pb 17
(2.1) µg/dL
Mean (SD) ALAD% 61.6
(28.3)%
Women
Mean (SD) blood Pb 11
(1.7) µg/dL
Mean (SD) ALAD% 72.6
(20.8)%
Using a computerized sway measurement system the exposed
workers had significantly increased mean body oscillations with eyes
closed (p < 0.01) and head tilted forward (p < 0.001). Partial
correlation adjusting for education, coffee consumption, hrs of sleep
and estimate of health was significant only for total Pb exposure and
increased body oscillations with head tilted forward (∃ = 2.25,
p = 0.0089). In order to maintain balance Pb exposed workers
required increased oscillations when visual and vestibular inputs
were altered.
Age adjustment controlled for by use of ratios of predicted to
observed values. A significant dose related decrease of R-R interval
variation during deep breathing was present in 132 workers with
stable blood Pb over the past yr (p < 0.01). This finding was more
prominent in younger workers with blood Pb ∃30 µg/dL but a mild
decrease present at blood Pb ∃20 µg/dL. A decrease in R-R interval
variation indicates decreased cardiac parasympathetic function.
22% had blood Pb >20 µg/dL, and 43% had ALAD%