Level of Heavy Metals and Potential Ecological Risks in Irrigated Horticultural Farms in the Vicinity of Lake Ziway, Central Ethiopian Rift Valley Region
Table 2
Percentage of recovery of the method used for soil and water samples analysed (mean ± SD, n = 3).
Heavy metals
Soil sample concentration (amount in mg/kg)
% recovery
% RSD
Water sample concentration (amount in mg/L)
% recovery
% RSD
A
B
C
A
B
C
As
0.105 + 0.004
1
1.248 + 0.002
114.3
4.15
0.16 + 0.006
4
4.25 + 0.04
102.2
6.67
Cd
0.032 + 0.002
1
1.087 + 0.015
105.5
6.57
0.01 + 0.001
4
4.03 + 0.05
100.5
5.59
Co
0.553 ± 0.021
1
1.727 + 0.015
117.3
3.76
0.01 + 0.002
3
3.40 + 0.03
113
11.78
Cu
0.343 + 0.021
1
1.463 ± 0.032
112
6.06
0.21 + 0.003
3
3.13 + 0.04
97.3
2.79
Cr
0.283 + 0.011
1
1.337 + 0.015
105.3
4.1
0.39 + 0.001
3
3.59 + 0.02
106.7
13.48
Ni
0.147 + 0.015
1
1.160 + 0.030
101.7
10.4
0.25 + 0.001
3
3.45 + 0.03
106.7
8.92
Pb
0.207 + 0.008
1
1.209 + 0.002
100.2
3.94
0.59 + 0.002
3
3.70 + 0.04
103.7
4.44
Hg
0.042 + 0.001
1
1.223 + 0.011
118.1
2.38
0.06 + 0.001
4
4.21 + 0.07
103.7
5.41
Zn
0.142 + 0.007
1
1.217 + 0.090
107.5
4.62
0.17 + 0.001
3
3.69 + 0.03
117.3
9.75
A = concentration before spiking, B = amount spiked, and C = concentration after spiking.
