Microbial and Heavy Metal Contamination Assessment in Restaurant Foods
A Quality Assurance Study from Erbil City, Kurdistan Region of Iraq
DOI:
https://doi.org/10.24086/cuesj.v9n2y2025.pp61-67Keywords:
Microbiological Contamination, Quality Assurance, Heavy Metals, Culture Media, Consumer NeedsAbstract
During this study, six different restaurants located in Erbil city were categorized, and a total of 96 samples were collected from them. Samples were gathered, and microbial and chemical tests were performed to evaluate fungal contamination and the presence of lead and cadmium as heavy metals. Final results indicated widespread microbial contamination across all food types tested. Escherichia coli and Staphylococcus aureus were among the most frequently isolated bacteria, detected in over 70% of samples. Fungal contaminants, including Penicillium, Aspergillus, and Candida species, were also commonly found, with contamination rates exceeding 50% in specific food categories. Heavy metal analysis revealed high levels of lead and cadmium in staple foods. Rice samples from some restaurants contained lead concentrations up to 1.56 ppm and cadmium up to 1.75 ppm, both exceeding international safety limits. Meat-based dishes also showed elevated cadmium levels reaching 1.52 ppm, while salads consistently tested below detectable limits. These findings underscore the urgent need for stricter hygiene protocols, routine screening for microbial and heavy metal contaminants, and targeted training for food handlers to reduce contamination and protect public health.
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Accepted 2025-08-14
Published 2025-09-20
