| S/N | Sample ID | Description |
| 1 | OC | Okobo coal |
| 2 | SS | Soil Sample |
| 3 | CSS | Control soil sample |
| 4 | WS | Water sample |
| 5 | CWS | Control water sample |
| 6 | CS | Cassava sample |
| 7 | CCS | Control cassava sample |