Element

Scope

(mg/kg)

Average

value

(mg/kg)

Standard deviation

(mg/kg)

Coefficient of variation (%)

Background values^①

Pb

18.4 - 529

93.8

106.6

113

40.6

Cd

0.22 - 1.9

0.7

0.38

56

0.218

As

7.19 - 53.9

26.3

17.06

65

18.4

Zn

66.9 - 271

144.5

51.28

35

89.7

Ni

16.1 - 85.6

39.3

15.53

39

42.5

Cu

14.6 - 138

47.4

26.38

56

65.2

Hg

0.027 - 0.199

0.1

0.05

65

0.058