Blood Lead Levels in Occupationally Exposed Workers Involved in Battery Factories of Delhi-NCR Region: Effect on Vitamin D and Calcium Metabolism

Abstract

Workers involved in battery manufacturing or recycling factories are occupationally exposed to high concentrations of lead. In humans, lead can cause a wide range of biological effects depending upon the level and duration of exposure. The purpose of this study was to find out the blood lead levels (BLL) in occupationally exposed workers involved in battery industry in Delhi NCR region and to study whether lead affected the vitamin D (vit D) and calcium metabolism. For this study 100 occupationally lead-exposed battery workers (LEBW) and 100 non-lead exposed controls (NLEC) were recruited. BLL were measured using inductively coupled plasma optical emission spectrometer (ICP-OES) technique while ELISA was performed to quantify the serum vit D levels in the study subjects. Routine biochemical parameters were measured by chemistry autoanalyzers. Statistical analysis was done using appropriate statistical tools. Results showed that BLL were significantly higher in LEBW as compared to NLEC (p \ 0.0001). Serum vitamin D, calcium and phosphorus levels were significantly decreased in battery workers as compared to controls (p \ 0.005). Spearman's rank correlation analysis showed significant negative correlation of BLL with serum Vitamin D and calcium levels. Significant positive correlation was observed between BLL and duration of lead exposure. Weak negative correlation was also observed between BLL and vit D even after adjusting for smoking status. In conclusion, this study demonstrated that higher BLL significantly alters the vit D and calcium metabolism.

Lower levels of vitamin D are associated with SARS-CoV-2 infection and mortality in the Indian population: An observational study

“… State/ union territories Case/million Death/million Total no. of healthy subjects Mean 25(OH)D levels (ng/ml) References Andhra Pradesh 5530 50 1936 18 [32] , [33] , [34] , [35] , [36] Assam 2390 6 768 26 [37] , [38] , [39] Bihar 940 4 50 30 [40] Chandigarh 1830 27 878 34 [41] , [42] , [43] , [44] , [45] , [46] Delhi 8970 249 2919 15 [47] , [48] , [49] , [50] , [51] , [52] , [53] , [54] , [55] , [56] , [57] , [58] , [59] , [60] , [61] , [62] , [63] , [64] , [65] , [66] , [67] , [68] Goa 7520 64 …”

Assessement of Blood Lead and Cadmium Levels in Occupationally Exposed Workers of Jodhpur, Rajasthan

“…Very few studies reported the occupational exposure of lead in the workers in India. Recently, Himani et al [26] demonstrated effect of higher BLL on Vit D and calcium status in battery workers of Delhi-NCR region. Singamsetty et al [27] reported incidence of higher BLL (25.26 ± 2.121 lg/dl) in battery workers of Andhra Pradesh.…”

Use of Generalized Additive Model to Detect the Threshold of δ-Aminolevulinic Acid Dehydratase Activity Reduced by Lead Exposure

“…One reason might be that the measurement of smoking and drinking was not precise enough, which was limited by the design of our study, evaluating these factors by questionnaire. Another possible reason was that both lead and alcohol deplete vitamin B12 and folate in serum, which may concomitantly affect the ALAD activity [ 7 ]. In addition, increasing oxidative stress from lead exposure and smoking may also affect ALAD enzyme activity via the prooxidant–antioxidant disequilibrium [ 30 ].…”

“…ALAD inhibition results in a buildup of aminolevulinic acid detectable in the plasma and urine. At the molecular level, lead displaces a zinc ion at the metal binding site, not the active site, producing inhibition through a change in the quaternary structure of the enzyme [ 5 , 6 , 7 ]. Thus, ALAD activity may be negatively related to higher blood lead levels.…”