Bacteriological and metal analyses of water samples from Awotunde fish pond and river

Abstract

The microbiological and metal analyses of water samples obtained from Awotunde fish pond and river in Ila-Orangun, Osun State, Nigeria were determined. The total bacterial and coliform counts were done using pour plating technique. Mineral was analyzed using Atomic Absorption Spectrophotometry techniques. The physicochemical parameters were done using standard methods. The total bacterial and coliform count of the water samples ranged 6.4 x 10 4 CFU/ml - 7.4 x 10 4 CFU/ml and 1.1 x 10 3 CFU/ml - 4.0 x 10 3 CFU/ml respectively. The values obtained for the physicochemical parameters ranged as follows: temperature (24 - 26) o C, HCO 3 (2.0 - 4.6), pH (6.0 - 7.2), alkalinity (40 - 100) mg/l, hardness (60 - 120) mg/l, conductivity (200 - 400)μS/cm, dissolved oxygen (1.1 - 2.0) mg/l, BOD (0.06 - 0.22) mg/l, chloride (28.4 - 106.4) mg/l, nitrite (4.0 - 188.0) mg/l, sulphate (14.0 - 640.0) mg/l, nitrate (0.0 - 90.0) mg/l and phosphate (1.6 - 83.2) mg/l. The mean values of the mineral contents of the water samples are as follows; potassium (94.4 mg/l), sodium (94.7 mg/l), magnesium (89.3 mg/l) and calcium (94.9 mg/l). The mean value obtained for the heavy metal concentrations are as follow; copper (0.1 mg/l), manganese (0.13 mg/l), nickel (2.09 mg/l), lead (0.03 mg/l) and iron (0.26 mg/l ). This shows that heavy metal concentrations were below critical limit according to the WHO standard. However, the microbial counts obtained portend the fact that the fish harvested from the pond might be a source of food poisoning if such fishes are not adequately cooked. Since the river serve as a source of water for domestic usage, an outbreak of water borne diseases could be imminent. Hence there must be a need for the Nigeria fish farmers to improve on their fish farming management which includes fish food preparation, environmental sanitation and monitoring the quality fish yield.