Faculty of Veterinary Medicine, Urmia University Food Safety and Packaging 3092-7668 2 1 2026 02 15 Microbiological quality and heavy metal contamination of ready-to-eat street-vended food wrapped in ink-printed papers in Dar-Es Salaam, Tanzania 25 32 121885 10.30466/fsp.2026.56788.1026 EN Ramadhan Abdul Hassan Department of Food Science and Agro-processing, Sokoine University of Agriculture, Morogoro, Tanzania 0009-0002-2390-3037 Davis Naboth Chaula Department of Food Science and Agro-processing, Sokoine University of Agriculture, Morogoro, Tanzania 0000-0002-4013-3786 Abdulsudi Issa-Zacharia Department of Food Science and Agro-processing, Sokoine University of Agriculture, Morogoro, Tanzania 0009-0001-1357-6944 Journal Article 2025 11 27 Street-vended food is perceived as a significant public health risk. Foods wrapped in ink-printed papers have been associated with several health issues, including cancer, neurological disorders, reproductive complications, and kidney and liver damages. This study examined heavy metal contamination and the microbiological quality of ready-to-eat foods (chapatti) wrapped in ink-printed paper in Dar es Salaam, Tanzania. Samples were collected and analyzed for lead (Pb), chromium (Cr), and cadmium (Cd) using microwave plasma atomic emission spectrometry. Microbiological assessment was conducted to determine the total plate count<em> </em>(TPC), and the presence of <em>Staphylococcus aureus</em> and <em>Escherichia coli</em>. Data analysis was performed using Python-based analytical tools to calculate mean values and assess statistical significance. The results indicated that the mean concentrations of Pb, Cr, and Cd were all significantly higher (p < 0.05) in the wrapped samples than in the unwrapped controls, with mean levels varying from 0.05–0.06 mg/kg, 0.07 mg/kg, and 0.06–0.07 mg/kg, respectively. Likewise, wrapped samples had significant microbial contamination, with mean TPC and <em>S. aureus</em> levels of 2.64 ± 0.17 log₁₀ CFU/g and 1.67 ± 0.16 log₁₀ CFU/g, respectively, while these bacteria were not present in the control samples. None of the samples tested positive for <em>E. coli.</em> Although measured heavy metal concentrations remain below current regulatory thresholds, the marked increase in contamination originating from ink-printed papers constitutes a potential public health concern. The results clearly demonstrate that the wrapping material is the principal source of contamination. Therefore, it is advisable that regulatory bodies, including the Tanzania Bureau of Standards and local government health officials, prohibit the use of printed materials, such as newspapers, for food contact.  https://fsp.urmia.ac.ir/article_121885_470093e83172cf246fd65582ecfb6bf8.pdf