Assessment on the levels of selected essential and non-essential metals in sesame seeds (Sesamum indicum L.) collected from Sheraro Town, Northwest Tigray, Ethiopia

Abstract

The purpose of this study was to determine the levels of essential and non-essential metals in sesame seeds (Sesamum indicum L.). Six sesame seed samples (three red and three white) were purchased randomly from six shops in Sheraro, Tigray, Ethiopia. The levels of Fe, Zn, Cu, Cd and Pb in the sesame samples were determined by FAAS. 5 g of dried and homogenized samples were digested using 30 mL of HNO₃ (70%) and 25 mL of HCl (37%) at 120 ^oC for 5 hours. The efficiency of the procedure was validated by spiking and the percent recovery for all studied metals varied from 90-120%. The mean levels of the metals (mg/kg) were found in the ranges 35.5-43.1, 58.1-67.0, 15.3-21.3, 0.202-0.262 and 0.08-0.114 for Fe, Zn, Cu, Cd and Pb, respectively. Analysis of variance at 95% confidence level indicated significant variations only for Cu and Zn. Thus, the sesame seeds analyzed are safe for human consumption.

KEY WORDS: Sesamum indicum L., Essential metals, Non-essential metals, FAAS, Shiraro, Tigray (Ethiopia)

Bull. Chem. Soc. Ethiop. 2019, 33(2), 191-202.

DOI: https://dx.doi.org/10.4314/bcse.v33i2.1