Determination of Beneficial and Toxic Metals in Fresh Palm Oil (Elaeis guineensis Jacq.) from South-Eastern Nigeria: Estimation of Dietary Intake Benefits and Risks

Abstract

The aim of this study was to determine the levels of twelve elements (Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni Pb and Zn) in samples of palm oil (Elaeis guineensis Jacq.) from eight (8) towns in Abia State, South-eastern Nigeria. Samples were collected from markets in 8 towns in January, 2013. A total of 32 samples (four samples from each town) were purchased and analyzed using flame atomic absorption spectrophotometer after acid digestion. Analysis of standard reference material as well as metal recovery study was used to validate the analytical method. Data obtained were used to estimate the daily intake of metals from the consumption of about 10 g of palm oil. The range of the results obtained for the beneficial elements (mg/kg) were: Mg (69–192), Ca (145–686), Mn (6.55-12.05), K (77–165), Na (115–533), Zn (3.6–14.6), Fe (65–232), Cu (0.56-2.09) and Cr (0.101-0.298), while values for toxic metals determined were Pb (0.024-0.067), Cd (0.024-0.089), and Ni (0.15-0.81). The results of this study have shown that palm oil will contribute to dietary intake of Zn, Mn, Fe, Cu, Ca, Cr, K, and Na; and that the levels of toxic metals Pb and Cd were low. Comparison of results with literature, and levels set by regulatory authorities indicate that the consumption of palm oil does not pose toxicological risk (from Pb and Cd) to consumers.