Heavy metal exposure through fish from the Korle Lagoon and Ghanaian markets: Implications for consumers

Sophie Leonie Steinhausen

With fish consumption above the world and African averages, seafood has a high nutritional and economic importance in Ghana. At the same time, anthropogenic activities are releasing pollutants in Ghana’s river and coastal areas, which contaminate aquatic ecosystems and can accumulate in aquatic biota. The Korle Lagoon in the center of Accra receives waste effluents from industries, households and the adjacent e-Waste burning site Agbogbloshie. Since exposure to heavy metals through contaminated fish can pose serious health risks to humans (Zhao et al., 2016), the analysis of heavy metals is needed to monitor contamination levels and assess health implications for consumers. We quantified concentrations of nine heavy metals (As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn) in fish from the Korle Lagoon and Ghanaian markets using ICP-MS technology. Concentrations of As, Hg and Pb were above reference limits set by the FAO/WHO and the European Commission. The daily intake of 224 g fish exceeded health risk indices of As and Hg concentrations. The results implicate health hazards for consumers dependent upon fish species, daily intake rate and consumption frequency. Following the precautionary approach, we propose further monitoring of the fish catches to protect consumer health and support restoration efforts in the Korle lagoon.