Abstract: The aim of this study was to estimate the activity of superoxide dismutase (SOD) and catalase in
erythrocytes and malondialdehyde (MDA) in plasma of battery manufacturing workers (BMW) of Western
Maharashtra (India) who were occupationally exposed to lead (Pb) over a long period of time (about 15 years). This
study was also aimed to determine the Pb intoxication resulted in a disturbance of heme biosynthesis in BMW group.
The blood Pb level of BMW group (n = 28) was found to be in the range of 25.8 – 78.0 μg/dL (mean +
SD, 53.63 +
16.98) whereas in Pb unexposed control group (n = 35) the range was 2.8 – 22.0 μg/dL (mean +
SD, 12.52 +
4.08).
The blood level (Pb-B) and urinary lead level (Pb-U) were significantly increased in BMW group as compared to
unexposed control. Though activated d- aminolevulinic acid dehydratase (ALAD) activities in BMW group did not
show any significant change when compared to control group but activated / non activated erythrocyte – ALAD
activities in BMW group showed a significant increase. Erythrocyte- zinc protoporphyrin (ZPP), urinary daminolevulinic
acid (ALA-U) and porphobilinogen (PBG-U) of BMW groups elevated significantly as compared to
control. A positive correlation (r = 0.66, p< 0.001) between Pb-B and ALA-U were found in BMW group but no such
significant correlation (r = 0.02, p> 1.0) were observed in control group. Hematological study revealed a significant
decrease of hemoglobin concentration, packed cell volume (%) and other blood indices and a significant increase of
total leucocytes count in BMW group in comparison to control group. The serum MDA content was significantly
increased (p< 0.001) and the activities of antioxidant enzymes such as erythrocyte- SOD (p< 0.001) and erythrocytecatalase
(p< 0.001) were significantly reduced in BMW group as compared to control group. A positive correlation (r
= 0.45, p<0.02) between Pb-B and serum MDA level was observed in BMW group (Pb-B range 25.8 – 78.0 μg / dL)
but such significant correlation did not notice in control group (Pb-B range 2.8 – 22.0 μg / dL).The study clearly
showed an adverse effect of heme biosynthesis and imbalance of pro-oxidant / antioxidant status in lead exposed
battery manufacturing workers resulting in increase in lipid peroxidation associated with decrease in erythrocyte-SOD
and erythrocyte-catalase activities.
