Microbial Density and Diversity and Lead Loads in Selected Street- Hawked Foods in Akure Metropolis, Nigeria

Abstract

Microbial density and diversity, as well as concentrations of lead, in selected street-hawked foods in Akure metropolis were investigated in this study. Street-vended/hawked foods offer numerous advantages to food security; nevertheless, the safety of street foods has been an issue of serious concern, mainly because of the poor sanitary standards and inadvertent contaminants. Seven selected food samples (zobo drink, rice and stew, African star apple, meat pie, cucumber, white pap, smoked fish) were purchased from vendors at three busy road intersections within the city. Metals were analyzed with atomic absorption spectrophotometry. The metals determined are Ca, Cu, Pb, Fe, Zn. The concentrations of the metals in mg/kg were in the range of Ca (24.50±0.10 to 32.00±0.10), Cu (0.75±0.03 to 1.12±0.01), Pb (0.05±0.01 to 0.30±0.01), Fe (0.19±0.01 to 0.31±0.01), and Zn (1.40±0.01 to 2.33±0.01). Lead values were well above permissible limits set by WHO, EU and USEPA, indicating a significant health risk. On the other hand, the presence of high concentration of calcium in the street hawked food indicates that the food is of good value. The microbial density of the street-hawked foods were as follows: zobo, rice and stew, African star apple and meat pie (52 x 10², 54 x 10², 2 x 10², 25 x 10² cfu/g), respectively. Only zobo drink had viable fungal counts (34 x 10² cfu/g) on Potato Dextrose Agar. The microbial isolates observed in this study were Escherichia coli, Klebsiella pneumonia, Shigella spp, Staphylococcus aureus, Bacillus cereus, in varied proportions which could be attributed to the utensils, exposure of food product environment and other related factors. Among the various microorganisms isolated from the street-hawked foods, Escherichia coli, Staphylococcus aureus and Bacillus cereus were quite prevalent. Some of the hawked street foods in Akure metropolis were of poor microbial quality, which is of public health concern.