| Experimental Exposure | Chemical Exposure | Age of Electrode | N |
| None | None | 1 week | 39 |
|
|
| 1 month | 8 |
|
|
| 2 months | 10 |
| None | Xylene | 1 week | 12 |
|
| Isopropanol | 1 week | 16 |
| In vitro | None | 1 week | 10 |
| In vivo | None | 1 week | 38 |
|
| Xylene | 1 week | 9 |
|
| Isopropanol | 1 week | 10 |
| - | - | - | 152 |