Abstract:
The objective of the study determined physico-chemical parameters in water, and the
concentration levels of metals in soil and water samples collected from Olonkomi town
West Shoa Zone, Oromia regional state, Ethiopia were analyzed. The soil and water
samples were digested following optimized procedures before Flame Atomic Absorption
Spectroscopy (FAAS) analysis for the metals. Appropriate standard sample preparation
and pretreatment procedures were also followed for the analysis of physicochemical
parameters. The results obtained revealed that the concentration of selected metals (Mg,
Na, K, Ca, Cu, Mn, Ni, Cr, Cd, Zn, and Pb) in the study sites the concentration of Mg and
Na were higher than all other metals in soil and water, respectively. The mean metals
concentration range in the soil and in the water samples were mg/Kg and mg/L Cu (33.2 -
45.88, 0 - 0.12), Mg (4554 - 4593, 4.9-5.8), Ca (771- 847, 16 - 44), Mn (1672 - 2158, 0.12),
Pb (15 - 50, 0.3 - 1),Cd (25 - 29,0 - 0.5), Cr (0 - 6.45, 0 - 0.13), Zn (146 - 163, 0 - 0.12), Na
(72 - 110, 68 - 69), K (1135 - 1196, 1.89 - 1.9), respectively. The water samples had been
analyzed for various physicochemical characteristics like pH, electric conductivity (EC),
Turbidity, Total dissolved solid (TDS), Total alkalinity (TA), Total hardness (TH), as well
as major chemical parameters like chloride, fluoride, phosphate, and sulfate. The results of
the physico-chemical parameters in the water showed range: TA (402.7 - 440.7) mg/L as
CaCO3, EC (47 - 536) µs/cm, Turbidity (1.05-38.63) NTU, TDS (316.33 - 362.67) mg/L,
pH (8.06 - 8.35), TH (60.67 - 130.67) mg/L as CaCO3, Cl-
(49.39 - 57.40) mg/L, F-
(1.98 -
3.08) mg/L SO4
-2
(79.90 - 237.40) mg/L, PO4
-3
(0.06 - 0.07) mg/L. The concentration of
fluoride was determined in both soil and water samples by using of ion-selective electrode
methods and the concentration range of the soil and water samples are (0.34 - 0.55)
mg/Kg. All the selective heavy metals and physico-chemical parameters of water analyzed
in the sampling sites were within the recommended standard limits except fluoride ion
which is slightly higher than the WHO guideline of 1.5 mg/L limit of drinking water.
