Concentrations of Metals in Tilapia (Oreochromis Niloticus) from Major Food Markets in Accra, Ghana

Abstract

Background: Fish is a primary protein source for many Ghanaians, with tilapia being a popular choice. Despite the health benefits of fish consumption, the presence of toxic metals like lead, cadmium, arsenic, and mercury poses risks to human health. Monitoring metal levels in fish is crucial to ensure food safety and protect consumers. Objective: This study aimed to assess metal levels in fresh tilapia (Oreochromis niloticus) from major markets in Accra. Method: Tilapia samples were obtained from four markets (Madina, Kaneshie, Makola, and Agbogbloshie) and analyzed for lead (Pb), arsenic (As), cadmium (Cd), mercury (Hg), and iron (Fe) concentrations using standard methods and Atomic Absorption Spectrometer. Statistical analysis was performed using Microsoft Excel 2016 and STATA. Results: Metal concentrations in tilapia heads and muscles varied across markets. For instance, in Kaneshie market, levels of Pb, Hg, As, Fe, and Cd were found to be (0.045 ± 0.025 mg/kg), (0.038 ± 0.0123 mg/kg), (0.02 ± 0.013 mg/kg), (9.5 ± 1.247 mg/kg), and (0.016 ± 0.006 mg/kg) in the head, respectively. In the muscle, the concentrations were (0.023 ± 0.01 mg/kg), (0.03 ± 0.011 mg/kg), (0.011 ± 0.0014 mg/kg), (2.88 ± 1.158 mg/kg), and (0.047 ± 0.029 mg/kg) for Pb, Hg, As, Fe, and Cd, respectively. Conclusion: While detectable, the metal levels in most analyzed tilapia samples remained within the permissible limits set by FAO/WHO. Therefore, tilapia sold in major Accra markets is considered safe for human consumption.