Determination of the Levels of Selected Essential and Non-Essential Metals In Canned Tomato Paste In Sebeta Town, Oromia Regional State Of Ethiopia

Abstract

Vegetables and Fruits have many similarities with respect to their compositions, methods of cultivation and harvesting, storage properties and processing. In the true botanical sense, many vegetables are considered fruits. Thus, tomatoes, cucumbers, peppers, and others were considered as fruits. The aim of this study was to determine the levels of selected essential and non-essential metals in three brands of canned tomato paste sold in sebeta town, oromia state, Ethiopia. A total number of three canned tomato paste samples (Ethiopia, Oman and China) were collected from mini Supermarket in Sebeta town by using systematic random sampling method. A wet digestion procedure, using mixture of HCl and H2O2 was developed for the decomposition of 0.5 g of canned tomato paste samples and flame atomic absorption spectrometry (FAAS) was used to determine Mn, Cu, Cr, Cd, Zn, Pb, Fe, K and Ca present in canned tomato paste sample .The one-way ANOVA showed that there is no significant difference among the sample means at 95% confidence level in mean concentration between all brand of canned tomato paste sample. Thus, a total of nine (9) mean concentration of essential and non-essential metals in mg/Kg as Potassium(6.07-11.77 ),Calcium (242.01- 442.45 ), Lead (ND), Zinc(32.85-62.07), Cadmium (ND), Manganese (0.24-11.63), Iron ( 168.03-360.66 ), Chromium ( ND), Copper (1.91-14.43 ) and When the performance of the method was investigated, the ranges of RSD (0.224-12.557) , accuracy (89.80 -109.26 %) which indicated that the method was precise and accurate. The LOQ (0.014-0.202mg/L), LOD (0.0044-0.1758) and the regression coefficient (R2 ) ranged from 0.9925 to 0.9989 showing good linearity. Therefore, the findings of this study was indicated that the levels of concentrations of heavy metals in the tomato paste purchased from mini Supermarket in Sebeta town did not constitute any serious threat presently .This is because most parameters were within the permissible limits of WHO and still acceptable and conducive to human bodies.