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

A Gebrekidan,A A Desta

doi:10.4314/bcse.v33i2.1

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 HNO 3 (70%) and 25 mL of HCl (37%) at 120 o C 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

Highlights

Sesame seeds (Sesamum indicum L.) are one of the edible seeds
The main objectives of this study were to determine the levels of essential (Fe, Zn and Cu) and non-essential metals (Cd and Pb) in Sesamum indicum L. which is commercially available in Shiraro town, Tigray, Ethiopia; compare the levels of these metals in red and white sesame seed samples; and compare the levels of these metals with values reported in the literatures
Six sesame samples purchased from shops of Sheraro town, Northwest Tigray, Ethiopia were analyzed for five selected metals using Fast Sequential Atomic Absorption Spectrophotometer (FAAS) using the acid digestion method

Summary

Introduction

Sesame seeds (Sesamum indicum L.) are one of the edible seeds. Food safety is considered to be one of the concerns of consumers of developed and developing countries. An increasing demand for food safety has initiated research works regarding the risk associated with consumption of foodstuffs contaminated by pesticides, heavy metals and/or toxins [3]. Food safety issues and its subsequent problems are among the serious public and environmental concerns. Preventing food items from heavy metal contamination is one of the important aspects of food quality assurance. The content of micro-essential and non-essential heavy metals in sesame (Sesamum indicum L.) is of great interest to consumers [7]

Objectives

Methods

Results

Conclusion