Assessment of Antinutrients, Heavy Metals, and Microbial Load in Street-Vended Foods from Port Harcourt, Nigeria

Authors

  • Owo Gogo James *

    Department of Biology, Faculty of Natural and Applied Sciences, Ignatius Ajuru University of Education, Port Harcourt 500102, Nigeria
  • Austin Achinike Okwelle

    Department of Biology, Faculty of Natural and Applied Sciences, Ignatius Ajuru University of Education, Port Harcourt 500102, Nigeria
  • Enyohwo Dennis Kpomah

    Department of Biochemistry, Faculty of Sciences, Federal University, Otuoke 562103, Nigeria

DOI:

https://doi.org/10.55121/fds.v2i2.773

Keywords:

Roadside Foods, Antinutrient, Heavy Metals, Microbial Quality, Food Safety, Port Harcourt

Abstract

Street-vended foods are a vital source of affordable nutrition for many urban dwellers but can pose serious public health risks due to several factors. This study evaluated antinutrient levels, heavy-metal contamination, and microbiological quality of abacha, tapioca, roasted plantain, fried yam, and okpa sold at key commercial areas in Port Harcourt. A stratified cross-sectional design was used, with 225 samples (15 per food type per site) collected from Eleme Junction, Artillery, and Waterlines. Antinutrients were determined spectrophotometrically, while heavy metals were analysed using inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrophotometry (AAS). Microbiological quality was assessed through total viable count (TVC), bacterial, coliform, and fungal counts expressed as log10 cfu/g. Abacha from Artillery showed the highest phytate (5.02 ± 0.21 mg/g) and tannin (3.28 ± 0.16 mg/g), while okpa from the same site had the highest saponin (3.02 ± 0.18 mg/g). Tapioca from Eleme Junction recorded the highest oxalate (2.56 ± 0.14 mg/g). Heavy-metal analysis revealed that roasted plantain from Artillery had the highest Pb level (176.4 ± 4.2 µg/kg), far above the WHO/FAO limit of 100 µg/kg; Cd (38.5–62.7 µg/kg) and As (45.6–58.3 µg/kg) also exceeded permissible limits, while Fe and Zn levels were relatively high. Microbiological findings showed TVC values ranging from 3.25–7.42 log10 cfu/g, with roasted plantain from Artillery recording the highest bacterial load, and coliforms most prevalent in abacha. Overall, foods sold at Artillery demonstrated the greatest contamination, highlighting the urgent need for stronger regulatory inspection and improved vendor hygiene training.

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