Table 4.
O6-POB-dGuo levels in (A) nasal respiratory mucosa, (B) nasal olfactory mucosa. Adduct levels are expressed as mean ± standard deviation (fmol/mg DNA).
| Dosagea | (R)-NNN | (S)-NNN | Rac-NNN | Additiveb |
|---|---|---|---|---|
| A. Nasal respiratory mucosa | ||||
| Low | 8c | NDd | 16 ±3 | NAe |
| Median | 22 ±3 | 9 ±1 | 24 ±6 | 31 ±3 |
| High | 31 ±5 | 23 ±4 | 41 ±3 | 54 ±7 |
| B. Nasal olfactory mucosa | ||||
| Low | NDd | NDd | 3c | NA |
| Median | 4 ±1 | NDd | 6 ±2 | NA |
| High | 9 ±1 | 3c | 12 ±4 | NA |
a
Low dosage level: 7 ppm (R)-NNN, 7 ppm (S)-NNN and 14 ppm racemic NNN; Median dosage level: 14 ppm (R)-NNN, 14 ppm (S)-NNN and 28 ppm racemic NNN; High dosage level: 28 ppm (R)-NNN, 28 ppm (S)-NNN and 56 ppm racemic NNN.
b
The additive sum was calculated from the corresponding enantiomers.
c
Two samples were quantified and the third sample was below LOD (n =2).
d
ND: not detected, limit of detection (LOD): 7 fmol/mg DNA for nasal respiratory mucosa; 2 fmol/mg DNA for nasal olfactory mucosa.
e
NA: not applicable.