Element | Proportion of sample points (%) | Index average | Index maximum | |||
No pollution | Slight pollution | Towards moderate pollution | Moderate pollution | |||
Cr | 99.07 | 0 | 0 | 0.93 | −0.86 | 2.41 |
Cd | 91.59 | 8.41 | 0 | 0 | −0.55 | 0.49 |
Pb | 96.53 | 3.74 | 0 | 0 | −0.38 | 0.15 |
As | 78.51 | 20.56 | 0.93 | 0 | −0.46 | 1.42 |
Hg | 89.72 | 7.48 | 2.8 | 0 | −0.89 | 1.84 |