Health risk assessment of lead and cadmium in roadside roasted corn from selected areas of Bwari Local Government Area, FCT, Nigeria

Abstract

This research examined the presence of lead and cadmium in roasted corn sold by roadside vendors. Five locations (Market Square, Ade Femi Street, Abiola Road, SCC Road, and Primary School) were selected for the research according to the availability of vendors and vehicular activities. Roasted corns were oven-dried at 80℃  and digested according to standard methods. The concentrations of lead (Pb) and cadmium (Cd) were determined with an Atomic Absorption Spectrophotometer. The data generated was analyzed with the R statistical program version 4.3.0. Lead and cadmium concentrations in the roasted corn varied significantly (p < 0.05) across the study locations. The Pb content of the roasted corn varied from 0.08±0.00 mg Kg^-1 – to 0.29±0.00 mg kg^-1 , While Cd was found to be within the range of 0.006±0.00 mg kg^-1 – 0.09±0.00 mg kg^-1 . Lead levels in roasted corn at Market Square were above WHO limits of 0.2 mg kg^-1 . However, the Cd levels were within the acceptable limit of 0.1 mg kg^-1. The strong positive correlation observed between Pb-Cd pairs in the roasted corn was a strong indication of similarity in the origin of the contamination. The potential risk associated with Pb and Cd exposure in roasted corn was determined by the Average Daily Intake of metals (ADI, Health Risk Index (HRI), and Incremental Lifetime Cancer Risk (ILCR). The risk assessment indices revealed that HRI was < 1, indicating a non-potential health risk for adults and children. Also, the estimated ILCR for Pb and Cd was within the acceptable limit of 1 x 10^-4 – 1x 10^-6 . This study shows that consumers of roasted corn sold at Market Square may be at risk of lead toxicity with continuous exposure.