A comparative is analysis on heavy metals in farmed fish from Akakai fish pond and wild Nile tilapia from Lalle landing site in Soroti district Teso sub-region

Abstract

Globally, both natural water bodies and aquaculture systems are being severely contaminated by heavy metals due to rising anthropogenic activities. Fish living in aquatic environments can easily accumulate metals in their bodies, which can then be transferred to consumers and put them at risk. This study assessed three heavy metals (lead, cadmium and arsenic) from edible muscles of Oreochromis niloticus from L. kyoga at Lalle landing site located in Lalle Parish, Kamuda Sub county and fish ponds owned by Paradise Integrated Fish Farmers (PIFF) in Akakai village in Arapai sub-county in Soroti district. Physicochemical parameters of water in the study area were analysed. Temperatures ranged between 27.8–29.2˚C, pH: 7.8–8.61. The levels of heavy metals in the tissues of Oreochromis niloticus from t farmed and wild were determined using Atomic Absorption Spectrometry (AAS). The maximum average concentrations of heavy metals observed in Nile tilapia fish tissues from both the wild and farmed in Soroti district were as follows As (2.923 µg/g) > Pb (0.118 µg/g) > Cd (0.0072 µg/g). The concentrations of the metals (Pb, Cd, and As) were below the recommended limit by WHO and FAO which are Cd (0.5 µg/g), As (10 µg/g) and Pb (0.5 µg/g). The mean differences between sample from farmed and the wild Oreochromis niloticus were not statistically significant and according to the results, eating tilapia from Soroti district both farmed and wild posed no risk to human health.