SN

Trace element pollution indices

Formulae

Reference

1

Degree of Contamination

$DC={\displaystyle {\sum }_{i=1}^n{C}_f^i}$

[25]

2

Enrichment factor

$ER=\frac{\left(Ci/Cie\right)\text{sample}}{\left(Ci/Cie\right)\text{background}}$

[26]

3

Ecological risk factor

$E_r^i=T_r^i\times C_f^i$

[27]

4

Ecological risk index

$R{I}_i={\displaystyle {\sum }_{i=1}^n{E}_r^i}$

[27]

5

pollution load index

$PLI=\sqrt[n]{C_{f1}\times C_{f2}\cdots C_{fn}}$

[28]

6

Geo-accumulation index

$I_{geo}={\log }_2\left[C_i/\left(1.5C_{ri}\right)\right]$

[29]