Lower Hematocrit is Associated with High Oxidative Stress and Low Antioxidant Status in Men Occupationally Exposed to Petrol

Abstract

Abstract Context: The organic compounds in petrol are known to adversely affect the hematopoietic system. Occupational exposure to these volatile compounds can lead to heightened oxidative stress and the consumption of antioxidants. Aim: This study aimed to assess the effect of occupational exposure to petrol on hematological parameters and markers of oxidative stress among petrol station pump attendants and roadside black market petrol vendors in a metropolitan city in Nigeria. Settings and Design: This is a comparative cross-sectional study that assessed the effects of occupational petrol exposure on hematological parameters, antioxidant vitamins (C and E), and oxidative stress marker – malondialdehyde (MDA) – of petrol station pump attendants and roadside black-market petrol vendors aged ≥18 years in Kano metropolis. Materials and Methods: Forty (40) participants were recruited from each of the three groups (n = 120). Healthy blood donors were recruited as a control group. Complete blood counts, reticulocyte count, and biochemical assays for vitamins C and E and MDA were performed using standard enzyme-linked immunosorbent assay methods. Analysis Used: Data were analyzed using R Studio v4.3.0. Mean values of laboratory parameters were compared between the three groups using analysis of variance, with Tunkey-HSD post-hoc analyses. A P value of <0.05 was considered significant. Results: There was significantly lower hematocrit (P = 0.0173) and higher mean corpuscular hemoglobin concentration (MCHC, P value = 0.0206) in occupationally exposed individuals (n = 80) compared to healthy controls. When compared by the duration of exposure (<2 yrs vs ≥2 yrs), only the mean granulocyte count was significantly different (P value = 0.009) in the two groups. Exposed individuals have significantly higher MDA (P value = 0.000) and lower vitamin C levels (P value = 0.031), with higher Vitamin E levels (P value = 0.015). Conclusion: Prolonged unprotected occupational exposure to petrol has adverse effects on the human hematopoietic system, possibly through oxidative stress and proinflammatory mechanisms.