Evaluation of Some Selected Metals in Rice Cultivated in Four Local Government Areas in Enugu State, Nigeria

Abstract

In this study, we investigated the presence of Zn, Fe, Cu, and Ca in rice cultivated in four local government areas (Nkanu East, Aninri, Uzo Uwani, Isi Uzo) within Enugu state, Nigeria. We employed an Atomic Absorption Spectrometer with an air acetylene flame to analyze these metals after digesting the rice samples. Risk assessment studies were carried out to determine any potential health risk to consumers by evaluating the estimated daily intake (EDI), the target hazard quotient (THQ) and hazard index (HI). The average concentration (mg/kg) of trace metals in the rice samples was within the acceptable limits established by FAO/WHO. Specifically, Zn ranged from 0.265 to 0.632 mg/kg, Fe from 2.73 to 4.131 mg/kg, Cu from 0.205 to 4.131 mg/kg, and Ca from 9.718 to 12.150 mg/kg. There were no statistically significant differences in metal concentrations among the various locations. Consequently, the rice analyzed in this study can be considered safe for consumption. The calculated EDI (mg/kg-day) values were below the maximum tolerable daily intake thresholds. THQ values also fell within safe levels, and the HI values were less than 1, signifying no potential health risks associated with consuming rice from these locations. In conclusion, there is no significant non-carcinogenic health risk associated with exposure to trace metals through the consumption of rice from these areas.