A COMPARATIVE STUDY OF TOXIC AND ESSENTIAL TRACE ELEMENTS IN CAT FISH SPECIES FROM LAKES AND FISH POND LOCATED IN SOUTH EAST, NIGERIA.

¹Olisah, C.M., ²Dioka, C.E., ²Meludu, S.C., ³Nwozor, C.M., ⁴Okafor, I.J.

¹Department of Medical Biochemistry, Anambra State University, Uli, Nigeria.

²Department of Chemical Pathology, Nnamdi Azikiwe University, Awka, Nnewi Campus, Nigeria.

³Department of Physiology, Anambra State University, Uli, Nigeria.

⁴Department of Anatomy, Anambra State University, Uli, Nigeria.

E-mail: corneliusnwozor@gmail.com   

ABSTRACT

The concentration of some toxic elements (mercury, lead, cadmium and arsenic) and some essential trace elements (cobalt, zinc, manganese, selenium, chromium and copper) in fish obtained from Oguta Lake, Agulu lake and fish pond in South East Nigeria were determined using a rapid, highly sensitive method. A stepwise digestion procedure using concentrated nitric acid and hydrogen peroxide was used for complete oxidation of organic tissues. The concentrations of the various elements were measured using Varian AA240 Atomic Absorption Spectrophotometer. A total of 46 fish samples covering three Species of cat fish namely: Clarias lazera, Clarias anguillaris and Clarias gariepinus were analyzed for their elemental contents. Results of the study indicate low level of exposure to mercury, cadmium, lead, chromium, zinc, copper, manganese, cobalt selenium and high level of arsenic and mercury in fish species found in Oguta Lake. Higher values of these toxic metals detected may pose a significant health risk to the individuals and to a greater extent the general population buying fish from this source.