Heavy Metal Concentrations in Fish and Water of Ajiwa Dam, Katsina State, Nigeria.

Abstract

In this current study determination of the physicochemical parameters of water and the concentration of 
heavy metals in catfish bone from Ajiwa dam, Katsina State, Nigeria, were conducted. Standard 
methods were employed in the sampling protocol and the analysis. The physicochemical parameters of 
the water were recorded as follows; pH ranges from 7.23±0.15 to 6.17±0.06, Turbidity ranges from 
196±1.73 to 148.67±2.08 mg/L, Hardness ranges from 47.14±0.01 to 40.41±0.02 mg/L, Nitrate ranges 
from 0.99±0.006 to 0.002±0.001 mg/L, Phosphate ranges 19.37±0.015 to 1.89±0.002 mg/L, Sulphate 
ranges from 23.40±0.53 to 15.00±1.00 mg/L, Electrical conductivity ranges from 105.37±0.32 to 
89.77±0.06 mg/L and Total Dissolve Solid ranges from 50.03±0.06 to 43.40±0.00 mg/L. The 
spectrophotometric method was used to evaluate the concentration of  Nitrates, Phosphates, Sulphates, 
pH, Total dissolved solids, and Electrical Conductivity, while the titrimetric method was used for the 
determination of hardness. The concentration of Zinc (Zn), Lead (Pb), Iron (Fe), Manganese (Mn), 
Copper (Cu), Cobalt (Co), Nickel (Ni), Cadmium (Cd), and Chromium (Cr) in catfish bone and water 
from Ajiwa dam were determined using Atomic Absorption Spectrophotometer (AAS). A total of seven 
samples each of catfish and water were collected and analyzed for heavy metals. Data obtained were 
subjected to an analysis of variance (ANOVA) test at a 0.05% confidence level, principal component 
analysis, cluster analysis, and Pearson correlation. The result showed that all the metal concentrations in 
both catfish bone and water were below the WHO recommended values: Pb (0.05 mg/l), Fe (10.1 mg/l) 
Zn (5.0 mg/l), Ni (0.02 mg/l), Cd (0.005 mg/l), Cr (0.05 mg/l), Co (0.05 mg/l) Cu (1.0 mg/l) and Mn 
(0.05 mg/l) for water and Pb (0.4 mg/l), Fe (3.0 mg/l), Cd (0.03 mg/l), Cu (2.0 mg/l), Mn (0.4 mg/l) Zn 
(3.0 mg/l) Cr (0.05 mg/l) Ni (0.02 mg/l) and Co (0.05 mg/l) for catfish bone. These findings indicate 
that the fish and water are safe for both aquatic life and human consumption.