Biochemical aspects of lead exposure in silver jewelry workers in western Maharashtra (India)

J Basic Clin Physiol Pharmacol. 2006;17(4):213-29. doi: 10.1515/jbcpp.2006.17.4.213.

Abstract

This study was conducted to examine the effect of blood lead (Lead) on heme biosynthesis, the hematopoietic system, oxidative stress, and antioxidant status of silver jewelry workers (SJW) in western Maharastra (India). The blood lead level of the SJW group (N = 30) was in the range of 30.2-64.7 microg dL(-1) (mean +/- SD, 48.56 +/- 7.39 microg dL(-1)), whereas that of non-occupational Lead-exposed normal healthy control subjects (N = 35) was 2.8-22.0 microg dL(-1) (mean +/- SD, 12.52 +/- 4.08 microg dL(-1)). Although the blood lead level of the SJW group increased significantly (p < 0.001) when compared with the control group, the urinary excretion of lead in the SJW group was not altered. In the SJW group, non-activated delta-aminolevulinic acid dehydratase (ALAD) activity significantly decreased (p < 0.05), and the ratio of activated/non-activated ALAD increased when compared with controls (p < 0.001), whereas activated ALAD activity was not altered significantly. Erythrocyte zinc protoporphyrin (ZPP) was not altered in SJW. The urinary excretion of delta-amino-levulinic acid (p < 0.001) and porpobilinogen (p < 0.05) of the SJW group increased significantly when compared with controls. Hematology parameters, such as the packed cell volume (p < .001) and total erythrocyte count (p < 0.05) significantly decreased, whereas the mean corpuscular hemoglobin concentration (p <.001) and total white blood cell count (p < .001) increased in the SJW group in comparison with controls. The serum malondialdehyde content significantly increased (p < .001), and the activities of antioxidant enzymes erythrocyte-SOD (p < .001), erythrocyte catalase (p < .05), and plasma ceruloplasmin (p < .001) significantly decreased in the SJW group compared with the controls. The results of the study clearly show an alteration of heme biosynthesis and cellular impairment of the pro-oxidants/antioxidants balance, resulting in oxidative damage in the silver jewelry workers group in western Maharashtra (India).

MeSH terms

  • Adult
  • Catalase / blood
  • Ceruloplasmin / metabolism
  • Enzymes / blood*
  • Heme / metabolism*
  • Humans
  • India
  • Lead / blood*
  • Lead / urine
  • Lipid Peroxides / blood
  • Male
  • Malondialdehyde / blood
  • Middle Aged
  • Occupational Exposure / adverse effects*
  • Porphobilinogen / urine
  • Porphobilinogen Synthase / blood
  • Protoporphyrins / blood
  • Reactive Oxygen Species / blood*
  • Silver*
  • Superoxide Dismutase / blood

Substances

  • Enzymes
  • Lipid Peroxides
  • Protoporphyrins
  • Reactive Oxygen Species
  • zinc protoporphyrin
  • Lead
  • Silver
  • Heme
  • Malondialdehyde
  • Porphobilinogen
  • Catalase
  • Superoxide Dismutase
  • Ceruloplasmin
  • Porphobilinogen Synthase