Evaluation of Heavy Metals in Local Chickens sold at Central Markets in Ado-Ekiti, Akure and Owena Towns

Abstract

Local chickens sold in the central markets of Ado-Ekiti, Akure and Owena were randomly sampled and slaughtered. Lead (Pb), cadmium (Cd) and zinc (Zn) in their blood and selected organs (intestine, heart, liver and gizzard) were isolated using wet digestion and their concentrations determined using atomic absorption spectrophotometer. Apart from the blood of chickens from Ado-Ekiti and Owena where Pb was not detected, its concentrations in the blood and organs of the chickens obtained from the three towns ranged from 2.00 to 7.33 mg/kg, exceeding the maximum tolerance levels (0.1 mg/kg) in internal organs of poultry birdsset by EU, ANZFA and FAO/WHO. With the exception of intestine of chickens from the three towns, Cd was only detected in the heart, blood and gizzard of chickens from Akure as well as liver and gizzard of chickens from Owena, covering a range of 0.11 to 0.67 mg/kg. The upper limit exceeded the maximum limits (0.5 mg/kg) according to FAO/WHO. Zn was detected in all selected parts of chickens from the three towns ranging 5.67 to 183.17 mg/kg. Its concentrations were within the permissible limit(10-50 mg/kg) by EU and FAO/WHO in certain selected parts of some chickens while it exceededthe permissible limit (150 mg/kg) by ANZFA especially in the liver of chicken from Ado-Ekiti. Some organs and blood of local chickens sold in the central markets at Ado-Ekiti, Akure and Owena may pose health risks.