| As | Cd | Cr | Fe | Mn | Ni | Pb | Zn |
Persaud and al. (1993) | 4.2 | 1.1 | 31 | 31,200 | 400 | 31 | 23 | 65 |
Calamari and Naeve, (1994) | 5.2 | 0.11 | - | 41,000 | 770 | - | 19 | 95 |