Distribution of metals in Labeo coubie (Ruppel, 1832) from a National Park river in Nigeria

Abstract

This study assesses heavy metals distribution in body parts of Labeo coubie (African carp) fromRiver Oli, in Kainji Lake National Park as pollution index of the ecosystem. Fish parts samples (gills, muscles andvertebra bone) were prepared and specifically analyzed for the levels of Pb, Cr, Zn, Cu, Fe and Cd using Atomicabsorption spectrophotometry. The concentration of metals in the samples at different concentrations ranged from0.001±0.000 μg/g for Cd to 224.87±4.07 μg/g of Fe in the fish gill. There is significant (p<0.05) differences in the Pb,Zn, Cu and Fe concentrations across the different fish parts with gills accumulated the highest levels metals while Crlevels significantly (p<0.05) differed in the fish body parts and accumulated more in the muscles (10.75±0.15 μg/g).The mean concentrations of metal elements in the fish parts had shown some distinguish connection in its distributionswith Pb and Cu; Gills > Muscles > Vertebra bones, Fe and Zinc; Gills > Vertebra bones > Muscles while Cr wasdistributed in Muscles > Gill > Vertebra bones. However, it is revealed that Labeo coubie, a euryphagus fish probablyabsorb these metals through ingestion of contaminated food or absorption by the gills and bioaccumulate in differentfish parts. It is therefore established that River Oli is contaminated with heavy metals as presence of these metals infish is an indication of its immediate environment.
 Keywords: absorption, bioaccumulation, fish parts, heavy metals, pollution