Some Heavy Metal Concentration in Catfish (Clariasgariepinus) and Tilapia Fish (Oreochromisniloticus) from Makoko and Olomore Fish Markets in Lagos and Ogun State, Nigeria

Abstract

Some heavy metal concentration in catfish and tilapia obtained from Makoko fish market in Lagos State and Olomore fish market in Ogun State, Nigeria was studied. Live matured and healthy fish samples were obtained directly from each fish market, conserved with water in a perforated covered bucket, and transported to the laboratory. Cadmium, manganese, iron, mercury, lead, nickel, chromium, and zinc were analyzed in the fish samples using inductively coupled plasma-mass spectrometry. The results showed that iron concentration ranged between 1.73 and 4.49 mg/ kg, cadmium ranged between 0.02 and 0.06 mg/ kg while range of mercury was 1.44-2.45 mg/ kg. Makoko fish market catfish had higher mercury concentration (2.45mg/ kg). Lead concentration in both markets tilapia fish ranged between 0.84 and 0.95 mg/ kg while that of catfish ranged from 1.20 to 1.23 mg/ kg, exceeding the maximum level (0.30mg/ kg) in fishes as recommended by the European Union, although it was within the maximum consumption per kg of body weight (25ug/ g).

Human exposure to toxic heavy metals on a cumulative basis has been implicated in some serious health issues particularly in most under developed countries globally.