Evaluation of Water Variables and Heavy Metals Concentration in Fish Species Collected from River Gurara at Izom, Niger State.

Abstract

Heavy metals are potentially toxic to human and the environment. Metals toxicity depends on the chemical form in which they exist. In this work, an evaluation of water variables and heavy metals concentration in fish species collected from River Gurara at Izom, Niger State were examined. Three stations were selected for the sampling and the metals investigated were Lead(Pb) (0.1-1.10);Iron(Fe)(5.61-20.7); Manganese(Mn) (0.02-0.06 and Copper(Cu) (0.6-0.90). The physicochemical parameters determined were Dissolved oxygen (D.O) (11.8-15.17mg/l), Biochemical oxygen demand (B.O.D) (9-16mg/l); pH(7.7-9.0);Electrical Conductivity(0.01-2.5μs/cm);Total dissolved solid (T.D.S) (67-133ppm); Temperature(24-270c); Sodium(Na) (4.2-6.83mg/l); Chlorine(Cl) (2.8-5.22mg/l); Potassium(k)(1.43-6mg/l); Nitrate(N03) (0.5-1.5mg/l)and Phosphorus(Po4) (0.11-3.5mg/l). The collected fish tissue was digested and analyzed using Atomic Absorption Spectrophotometer (A.A.S.).The mean concentration of heavy metals showed that copper (0.6-0.90) in the fish species was not significantly (P>0.05) different in all species sampled. Iron was found to be above the maximum acceptable limit (0.3mg/l) by WHO. Similarly, manganese was slightly lower compared with iron, Lead was within the maximum acceptable limit (0.01mg/l) While pH was neutral in all stations, Temperature was within the range of 24-270C. Dissolved oxygen and Biochemical oxygen demand fluctuated slightly between (11.8-18.2mg/l) and (9-16mg/l) respectively. Although, this values were relatively moderate, there effect on most organic contaminants are weak organic acids, and are more likely to enter organisms at low pH because they are un-ionized. The fish species collected within the study period were Chrysicthys walker sp.; Tylochromis jentinki sp., Hepsetus odoe sp., Barbus callipterus, Brycinus nurse, Petrocephalus sp.and Alestes baremose. The findings indicated that the water have high level of total dissolved solids, slightly Alkaline and the high concentration of Iron in fish species, showed that the water was contaminated.