Elements concentration (μg/g)

Ca

Cu

Fe

Pb

Zn

Cr

Cd

Mg

Ni

Average

2159

3.4

106

9.2

27

<0.1

<0.1

172

<0.04

Maximum

3884

8.4

367

11

47

<0.1

<0.1

197

<0.04

Minimum

777

0.6

1.4

4.8

7.4

<0.1

<0.1

116

<0.04