Hazard Identification and Potential Risk Analysis of Toxic Metals in Redbelly Tilapia (Coptodon zillii) Consumed and Surface Water from the Niger Delta Estuary

Abstract

Anthropogenic activities have caused toxic metals to escalate, polluting rivers, and accumulating in water, sediments, and fish. This harms aquatic ecosystems and has enduring impacts on humans and aquatic life. The study aimed to assess the accumulation of heavy metals (Pb, Cr, Cu, Fe, Ni, Cd, and Zn) in Redbelly tilapia (Coptodon zillii) and water obtained from three sampling stations along Atuka Creek which is a crude oil-contaminated site in a southern creek in Nigeria. The investigation further intends to evaluate potential health risks linked to the consumption of C. zillii and to analyze the pollution and productivity levels of the corresponding aquatic ecosystem. The results show significant variations in heavy metal concentrations across stations, with Station 1 exhibiting the highest contamination levels attributed to its proximity to pollution sources. The fish from Station 1 revealed elevated levels of contamination, surpassing recommended limits for Pb, Fe, Ni, and Zn. Calculations of chronic daily intake (CDI) values indicate potential health risks for both adults and children, particularly in Stations 1 and 2. The hazard quotient (HQ) and hazard index (HI) values surpassed safe limits in these stations, suggesting non-carcinogenic health risks linked to fish consumption and swimming. Moreover, lifetime cancer risk (ILCR and TLCR) assessments revealed an augmented risk of cancer, especially in Stations 1 and 2. These findings emphasize the need for stern pollution control measures, regulations, and remediation strategies to mitigate heavy metal contamination, ensure water quality, and safeguard public health in southern Nigerian communities.