Biological Evidence 2018, Vol.8, No.3, 21-31
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Table 1 Standard for comparison for the various indices
Indices
Contamination factor
(CF)
Contamination degree
(CD)
Ecological risk
(ER)
Ecological risk
Index (R’)
Pollution load index (PLI)
Geo-accumulation index (Igeo)
Low risk
CF<1
CD<8
Er <40
R’<150
No pollution
PLI<1
Uncontamination
Igeo ≤ 0
Moderate risk
1 ≤ CF<3
8 ≤ CD<16
Er 40 ≤ Er <80 150≤ R’<300
-
-
Uncontaminated to moderately
contamination
0<Igeo ≤ 1
Considerable
3≤ CF<6
16 ≤ CF<32
80 ≤ Er<160
300≤ R’<600
Moderate
1<PLI<2 Moderate contamination
1<Igeo B≤2
High risk
-
-
160 ≤ Er <320 -
Heavy pollution
2<PLI<3 Moderate to heavy
contamination
2<Igeo ≤ 3
Very high
CF ≥ 6
CD>32
Er ≥ 320
R’≥ 600
Extremely heavy pollution 3<PLI
Heavy contamination
3<Igeo ≤ 4
-
-
-
-
-
-
-
Heavy to extremely
contamination
4<Igeo ≤ 5
-
-
-
-
-
-
-
Extremely contaminated
Igeo ≥ 5
Note: Geo-accumulation index is by Muller (1969) have been widely applied by Ghaleno et al. (2015), Bhutiani et al. (2017), Todorova et al. (2016), Izah et al. (2017c); Note: CF, CD, ER, R”
was developed by Hakanson (1980) and have been widely applied by Bhutiani et al. (2017), Izah et al. (2017d, 2018), Singovszka et al. (2014), Todorova et al. (2016); PLI have been widely
applied in environment risk assessment by Tomlinson et al. (1980), Bhutiani et al. (2017), Izah et al. (2017d)
