DETERMINATION OF PHYSICO-CHEMICAL PARAMETERS AND SELECTED HEAVY METALS FOR DRINKING WATER SUITABILITY OF LAKE ZENGENA,AWI ZONE,AMHARA REGION,ETHIOPIA

Abstract

The determination of the physico-chemical parameters & heavy metals of any lake is important. The water quality test will identify weather the water is suitable for different purposes. This study aimed to determine the levels of some physico-chemical parameters and elements in Lake Zengena, Awi zone, Amhara regional state, Ethiopia using Atomic Absorption Spectrophotometer (AAS) & Palintest Photometer. For this study, six water samples were collected from two Lake Sites. Samples of the water from Lake Zengena were collected according to standard laboratory guideline for the analysis of water quality parameters & metals. The following water quality parameters were measured in the laboratory and in the field: temperature; pH; Electrical conductivity; TDS; turbidity, total hardness, dissolved oxygen, & BOD. There are two field sites and they were selected due to their differences in their position of the chance the contaminant can enter. The mean & standard deviation of the results obtained were - pH (6.82±0.057) for site one & (6.62 ± 0.00816) for site two, electrical conductivity (203.3 ±0.15 μs/cm) for site one & (199.1 ± 0.471 μs/cm) for site two, temperature (20.63± 0.057 0C) for site one & (20.13 ± 0.0416 0C) for site two. Total dissolved solids (20.5 ± 0.1 mg/l) for site one & (18.23 ± 0.124) for site two, turbidity (0.52 ±0.015 NTU) for site one & (0.41± 0.00816NTU) for site two, total hardness (44.5 ±0.1 mg/l) for site one & (41.4 ± 0.081mg/l). Dissolved oxygen (7.16 ±0.11) for site one & (6.3 ± 0.0816) for site two, biological oxygen demand (22.46± 0.05) for site one & (20.3 ± 0.0816) for site two. In addition, chemical oxygen demand (104.56 ± 0.057) for site one and (102.16 ± 0.0471) for site two, alkalinity (90.16 ±0.11 mg/) for site one & (80.26 ± 0.124) for site two. In addition, the results of metals in water sample were as follow:-Pb, Cr & Ni were bellow detection limit. Ca (0.63 ± 0.02) for site one & (0.83 ± 0.016) for site two, Mg (0.31 ± 0.02) for site one & (0.43 ± 0.0.0081) for site two, Zn (1.65 ±0.01) for site one & (1.85 ± 0.0081) for site two, K (5.8 ± 0.1) for site one & (4.66 ± 0.047) for site two. Fe (0.13 ± 0.02) for site one & (0.12 ± 0.0081) for site two, Cu (0.67 ± 0.015) for site one & (0.76 ± 0.0244) for site two. The statistical data analysis by using t-test shows that there was no significance difference between analyzed metals in site one and site two at (p < 0.05). The results of physico-chemical parameters & metals indicate that Lake Zengena is safe for the use of human being according to WHO