Impaired Antioxidant-Defence Status in Nigerian Children with Elevated Blood Lead Levels: A Possible Predisposing Factor to Chronic Diseases.

Abstract

Background: Lead, a prime environmental toxicant and multi-organ poison, exerts its toxicity through interaction with essential metals and the generation of free radicals. Aim and Objectives: To explore and elucidate possible interaction dynamics between lead and the antioxidant-defence status in apparently healthy children with Elevated Blood Lead Level (EBLL) in Ibadan, South-West, Nigeria. Material and Methods: Three-hundred-and-nine apparently healthy, public primary school children were grouped into 169 children with EBLL (BLL > 5µg/dL) and 140 control (BLL≤ 5µg/dL). Blood lead (Pb), plasma enzymatic antioxidants [Superoxide Dismutase (SOD) and Glutathione Peroxidase (GPx) activities], antioxidant metals [Copper (Cu), Zinc (Zn), Selenium (Se)], and oxidative stress parameters [Total Antioxidant Potential (TAP), Total Plasma Peroxide (TPP) and Oxidative Stress Index (OSI)] were determined. Results: Levels of Pb, Zn, Se, TPPand OSI increased while SOD, GPx and TAP decreased in children with EBLL compared with control (p 0.05). Lead associated positively with Se, TPP and OSI (p0.05). Conclusion: There was impaired antioxidant-defence status in children with EBLLs which may predispose them to chronic diseases if unresolved.

Keywords

• antioxidants
• essential metals
• lead exposure
• free radicals
• oxidative stress index
• total antioxidant potential
• total plasma peroxide