The behavior of a given element in soil (i.e., the determination of its accumulation or leaching) may be established by comparing concentrations of a trace element with a reference element. The result obtained is described as an enrichment factor (EF). The reference element may be Fe or Al or some other elements. Cn is content of the examined element in the soil, Cref is content of the examined element in the Earth’s Crust, Bn is content of the reference element in the soil, and Bref is content of the reference element in
the Earth’s Crust.