Heavy Metal Assessment of Claris angullaris and Tilapia zilli from Omambala River, Anambra State, Nigeria
Dibua Nwamaka Anthonia *
Chukwuemeka Odumegwu Ojukwu University, Uli, Anambra State, Nigeria.
Ezeanwu Bibian Amaka
University of Nigeria Nsukka, Enugu State, Nigeria.
Chude Charles Onuora
Chukwuemeka Odumegwu Ojukwu University, Uli, Anambra State, Nigeria.
Eleanya Lilian Chinyere
Chukwuemeka Odumegwu Ojukwu University, Uli, Anambra State, Nigeria.
Okoye Elochukwu Chidubem
Chukwuemeka Odumegwu Ojukwu University, Uli, Anambra State, Nigeria.
Adamu Jacob Eshiemokhai
Federal Polytechnic Ede, Osun State, Nigeria.
Agbo Bernadine Chikodili
Federal Polytechnic Oko, Anambra State, Nigeria.
Okpala Victor Chisom
Chukwuemeka Odumegwu Ojukwu University, Uli, Anambra State, Nigeria.
Oradubanya Olives Kosisochukwu
Chukwuemeka Odumegwu Ojukwu University, Uli, Anambra State, Nigeria.
Ngonadi Ujunwa Juliet
Chukwuemeka Odumegwu Ojukwu University, Uli, Anambra State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Fish is a major source of food in many parts of the world, because they contribute to solving global food problem and providing adequate proportions of proteins, minerals, vitamins and trace elements. Concentrations of iron (Fe), nickel (Ni), zinc (Zn), lead (Pb) and cadmium (Cd) were determined in organs of fish species (Tilapia zilli and Claris angullaris) caught from Omambala River, Anambra State, Nigeria. The fishes were caught overnight with the aid of nets cast by the local fishermen. Fish tissues/organs (muscles, liver, kidneys and gills) were digested and the concentrations of the heavy metals determined using the Atomic Absorption Spectrometer (AAS 220FS). Heavy metals and physicochemical parameters of the water samples were also analyzed, using same AAS. Health risks related to Fe, Ni, Zn, Pb and Cd were assessed based on target hazard quotient (THQ). Results showed varying degrees of heavy metal concentrations across organs/tissues in the fish samples. There were higher concentrations of heavy metals in the gills than in other organs of the fish samples. The concentration of Pb was highest concentration in all the organs of the fish samples. The trend of bioaccumulation of the heavy metals in fish organs is presented in descending order of the most prevalence as; Pb (0.660±0.244) > Fe > (0.454±0.544) > Zn (0.345±0.108) > Cd (0.029±0.008). The concentration of Fe was at maximum in the kidneys of the two fish species. Highest accumulation of Zn and Pb were detected in gills of T. zilli and C. angullaris. Overall, the analyzed heavy metals were all detected in the organs of the two fish species except Pb and Cd which were not detected in the kidney and muscle of C. angullaris respectively. Heavy metals and physicochemical analyses of the water samples revealed most parameters and metals were within the World Health Organization (WHO) and Nigerian’s National Environmental Standards and Regulations Enforcement Agency (NESREA) maximum permissible limits. The THQ values for Pb in the muscles of Tilapia zilli were greater than 1, indicating high health risks related to heavy metals from the fish consumption. THQ values of other heavy metals in the muscle of C. angullaris and T. zilli were less than 1, indicating no risk from the fish consumption. The heavy metal concentrations and physicochemical parameters of the water were within the WHO and NASREA standard limits.
Keywords: Heavy metals, Claris angullaris, Tilapia Zilli, fishes, target hazard quotient, health risk assessment, Omambala River