Biochemical Effects of Lead Exposure on Systolic &; Diastolic Blood Pressure,Heme Biosynthesis and Hematological Parameters in Automobile Workers of North Karnataka (India)

The purpose of this study was to find out the effect of lead exposure on systolic and diastolic blood pressure, heme biosynthesis related and hematological parameters of automobile workers. For this study 30 automobile workers were selected and compared with 30 age matched healthy control subjects. Significantly increased blood lead (364%, P < 0.001) and urinary lead (176%, P < 0.001) levels were observed in automobile workers (study group) as compared to controls. Systolic blood pressure (5.32%, P < 0.05) and diastolic blood pressure (5.87%, P < 0.05) were significantly increased in the automobile workers as compared to controls. The significantly decreased non-activated erythrocyte δ-aminolevulinic acid dehydratase (δ-ALAD) (−18.51%, P < 0.01) and activated δ-ALAD (−13.29%, P < 0.05) levels were observed in automobile workers as compared to normal healthy control subjects. But the ratio of activated/non-activated δ-ALAD was significantly increased (43.83%, P < 0.001) in automobile workers as compared to controls. Excretions of δ-aminolevulinic acid (83.78%, P < 0.001) and porphobilinogen (37%, P < 0.001) in urine were significantly increased in the study group as compared to the controls. In automobile workers heamoglobin (−11.51%, P < 0.001), hematocrit (−4.06%, P < 0.05), mean corpuscle volume (−3.34%, P < 0.05), mean corpuscle hemoglobin (−5.66%, P < 0.01), mean corpuscle hemoglobin concentration (−7.67%, P < 0.001), red blood cell count (−14.6%, P < 0.001) were significantly decreased and total white blood cell count (11.44%, P < 0.05) increased as compared to the controls. The results of this study clearly indicate that the absorption of lead is more in automobile workers and it affects on blood pressure, heme biosynthesis and hematological parameters observed in this study group.     

Impact of Chronic Lead Exposure on Selected Biological Markers

Lead poisoning remains a major problem in India due to the lack of awareness of its ill effects among the clinical community. Blood lead, δ-aminolevulinic acid dehydratase (δ-ALAD) and zinc protoporphyrin (ZPP) concentrations are widely used as biomarkers for lead toxicity The present study was designed to determine the impact of chronic lead exposure on selected biological markers. A total of 250 subjects, of both sexes, ranging in age from 20 to 70 years, were recruited. On the basis of BLLs, the subjects were categorized into four groups: Group A (BLL: 0–10 μg/dl), Group B (BLL: 10–20 μg/dl). Group C (BLL: 20–30 μg/dl) and Group D (BLL: 30–40 μg/dl) having BLLs of 3.60 ± 2.71 μg/dl, 15.21 ± 2.65 μg/dl, 26.82 ± 2.53 μg/dl and 36.38 ± 2.83 μg/dl, respectively. Significant changes in biological markers due to elevated BLLs were noted. The relation of BLL and biological markers to demographic characteristics such as sex, habits, diet and substances abuse (smoking effect) were also studied in the present investigation. Males, urban population, non-vegetarians, and smokers had higher blood lead levels. δ-ALAD activity was found to be significantly lower with increased BLL (P < 0.001), while the ZPP level was significantly higher with increased BLL (P < 0.001). Further, BLL showed a negative correlation with δ-ALAD (r = −0.425, P < 0.001, N = 250) and a positive correlations with ZPP (r = 0.669, P < 0.001, N = 250). Chronic lead exposure affects the prooxidant-antioxidant equilibrium leading to cellular oxidative stress.