Toxicity of Trace Metals in Mangrove Oysters (Crassostrea Gasar) and the Associated Health Risk from Bundu-Ama Community in Rivers State
DOI:
https://doi.org/10.54536/ajaas.v5i1.6498Keywords:
Bundu-Ama, Crassostrea Gasar, Health Risk Ssessment, Isaka-Bundu Mangrove, Nigeria, Rivers State, Trace MetalsAbstract
Mangrove oysters (Crassostrea gasar) serve as important food sources in coastal communities but are at risk of accumulating toxic metals from polluted waters. This study quantified cadmium (Cd), chromium (Cr), zinc (Zn), and nickel (Ni) in oysters collected from three anthropogenically impacted stations within the Isaka-Bundu mangrove swamp (Bundu-Ama community, Rivers State, Nigeria). Oyster samples were analyzed using Atomic Absorption Spectrophotometry (AAS), and health risk parameters such as Chronic Daily Intake (CDI), Hazard Index (HI), and Carcinogenic Risk (CR) were computed using standard USEPA models. Findings showed that metal concentrations varied spatially across the stations: Ni concentrations were highest (8.142 mg/kg at Station 1) and greatly exceeded the FAO/WHO limit of 0.05 mg/kg. Zinc reached 9.965 mg/kg (Station 1) but remained below the 30 mg/kg limit. Cadmium levels (0.007–0.012 mg/kg) slightly exceeded the 0.005 mg/kg threshold, while Cr (0.015–0.032 mg/kg) was within safe limits. The combined non-carcinogenic Hazard Index (HI) was below 1 for adults (0.583–0.900), indicating tolerable risk, but exceeded 1 for children (2.721–4.202), suggesting potential non-carcinogenic health effects. Carcinogenic Risk (CR) values for Ni and Cr were above the acceptable USEPA range of 10E⁻⁶– E10⁻⁴, implying potential lifetime cancer risks for frequent consumers particularly children. It was concluded that oysters from the Isaka-Bundu mangrove swamp are contaminated with trace metals, especially nickel, posing possible health hazards to the local population. The study recommends regular monitoring of seafood, enforcement of effluent discharge control, and community sensitization on safe seafood consumption.
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Copyright (c) 2026 Davies Ibienebo Chris, Sibe Lebari, Enyi Ikpechi Ovundah, Sulaiman Yusuf
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