Differential expression of heavy metals in fresh water and fishes in Southwestern Uganda.

Abstract

The consumption of fish Worldwide has exponentially increased in recent years due to awareness of its nutritional and therapeutic benefits. Moreover, a lot of populations globally depend on fish as part of their daily diet since it provides many essential nutrients such as high value proteins, various vitamins and minerals and polyunsaturated Omega-S, fatty acids. However, fish usually accumulate heavy metals from water, sediment and food which is a good indicator of heavy metal contamination in water. The general objective of the study was to determine the heavy metal concentrations in fresh water and fishes of south-western Uganda. The specific objectives of this study were: To determine the concentrations of Cd, Pb and Zn in fresh water and fishes of south-western Uganda, to compare the concentrations of heavy metals in fresh water and fishes of south western Uganda against international limits. The study showed that fish in south-western Uganda are able to bio accumulate heavy metals even above the set limits of WHO, EU, and USEPA. Furthermore, major public health risks identified in the study were the, presence of Pb in Oreochromis niloticus and Cd in Brycinus nurse. Concentrations of Zn in Brycinus nurse were-adequate as per International standards while Bagrus docmak and Oreochromis niloticus were below quality. In addition, low concentrations of Pb in Brycinus. nurse demonstrate its importance to human nutrition over Oreochromis nilotcus which bio accumulate Pb above international limits