As

Pb

Cd

Hg

Cr

Effect Level

PTEs’ Mean Concentration

0.38

4.58

0.27

0.14

27.51

TEL^a

5.9

35

0.6

0.17

37.3

Threshold

ERL^a

33

35

5

0.15

80

LEL^a

6

31

6

0.2

26

PEL^a

17

91.3

3.53

0.486

90

Midrange

ERM^a

85

110

9

1.3

145

SEL^a

33

250

10

2

10

Extreme