The total mean concentrations of the metals (mg/kg)
were Cr = 2.70 ± 0.7, Cd = 27.8 ± 8.0, Pb = 73.8 ± 42.3
and As = 222 ± 34.1 as also shown in Figure 1. This
shows that As has the highest and Cr the least concentration.
The total coefficient of variation were; Cr = 26%,
Cd = 29%, Pb = 57%, and As = 15%. This indicates that