Study of hematological indices in tannery workers exposed to chromium in Sheikhupura (Pakistan)

Chromium (Cr), being an excellent tanning agent, is widely used in the leather industry and tannery workers (TW) are exposed to it either in the form of inorganic Cr(III) compounds or Cr bound to proteins (leather dust) in the process of leather production. During the present study, the effect of Cr on the hematological indices in TW was evaluated. In this study, hematological indices of 92 male TW aged 20-60 years were compared with 79 control males who hardly had a chance of exposure to chromium. Both groups were subdivided into four age groups with an interval of 10: group A, 20-29 years; group B, 30-39 years; group C, 40-49 years; group D, 50-60 years. Total erythrocyte count (TEC) was significantly lower (p < 0.05) in TW of age group A, B and C than control subjects. Packed cell volume (PCV) was significantly higher (p < 0.05) in TW of age group B while mean corpuscular hemoglobin (MCH) was significantly lower (p < 0.05) in TW of age group D. Within the TW, MCH was significantly lower (p < 0.05) in the age group D as compared to age group A and B. No significant changes were observed in the values of hemoglobin, mean corpuscular volume and mean corpuscular hemoglobin concentration between TW and control individuals. The low values of TEC, PCV and MCH might be a result of chromium exposure in the tannery workers and may act as indicators of chromium toxicity.