Bioaccumulation of Cadmium in Tilapia (Oreochromis Niloticus) from Kangimi Dam and the national water resources institute, Kaduna, Nigeria

Abstract

The bioaccumulation of cadmium (Cd) in Tilapia fish (Oreochromis niloticus) was evaluated between September and October 2024 in Kaduna Metropolis, Nigeria. Fish samples were collected from Kangimi Dam and the National Water Resources Fish Ponds, and cadmium concentrations in the gills, kidneys, and livers were investigated using Atomic Absorption Spectroscopy–High-Performance Liquid Chromatography (AAS-HPLC). ANOVA was used to determine mean concentrations. In Kangimi Dam fish, cadmium levels were 0.045±0.011 mg/kg (gills), 0.056±0.006 mg/kg (liver), and 0.055±0.012 mg/kg (kidneys). In contrast fish from the National Water Resources Fish Ponds, concentrations were higher: 0.098±0.004 mg/kg, 0.107±0.001 mg/kg, and 0.097±0.006 mg/kg, respectively. The liver showed the highest accumulation, though differences across organs were not statistically significant (p > 0.05). Cadmium concentrations remained within the WHO/FAO permissible limit (0.05 mg/kg), suggesting no significant health risk. Further studies on other heavy metals and their bioaccumulation factors in the study area are recommended.