Cr

Cu

Zn

Unit

ppm

ppm

ppm

FS-ST

38 ± 6.16

395.17 ± 11.71

113.33 ± 44.98

FS-STT

58.17 ± 9.83

424.33 ± 43.96

142.50 ± 70.32

SS

36.83 ± 62.90

403 ± 24.39

110.50 ± 38

EUC standards

100

1000 - 1750

2500 - 4000