Mycotoxin and metallic element concentrations in peanut products sold in Ugandan markets

Abstract

The increasing prevalence of cancer among Ugandans has aroused consumer concerns about food-borne carcinogens. This study sought to compare mycotoxin and metallic element concentrations in processed peanuts sold in selected markets in Kampala, Uganda to those traditionally prepared in homes. Market-processed peanut samples (n = 33) were purchased from four markets. Control samples (n = 5) were unground peanuts bought from markets but processed in homes by traditional methods. Aflatoxins B1, B2, G1, G2; Fumonisins; Deoxynivalenol, Nivalenol, Ochratoxin A, T2 toxin, Zearalenone, and Zearalenol were analyzed by LC/MS/MS while As, B, Ba, Cd, Cr, Cu, Hg, Mg, Ni, Pb and Zn were analyzed by ICP/MS. The data was statistically analyzed using Wilcoxon scores (rank sums) or the Kruskal-Wallis test. Aflatoxins were the predominant mycotoxins found in significant amounts. 55 and 34% of the samples had concentrations of total aflatoxins greater than 20 ppb (FDA acceptable limit). There were significantly higher concentrations of aflatoxins in market-processed than in home-processed samples. Metallic element concentrations were generally below FDA maximum acceptable concentrations. Roasting and duration of grinding had no significant effect on aflatoxin or metallic element concentrations. There is a need for food-borne toxicant monitoring of food sold in public markets in Uganda.