Table 3. Exposure concentrations and estimated deposited doses.
| Estimated deposited dose (μg) |
||||||
|---|---|---|---|---|---|---|
| LRT |
||||||
| Material | Total concentration (mg/m3) | Inhaled volume over 60 min (L) | PUL | TB | URT | Total deposited in airways |
| ZnO_1 | 6 | 2.594 | 0.04 | 0.14 | 2.12 | 2.30 |
| 58 | 2.024 | 0.41 | 1.37 | 20.6 | 22.3 | |
| 203 | 1.296 | 1.45 | 4.79 | 72.1 | 78.1 | |
| ZnO_2 | 4 | 3.489 | 0.02 | 0.09 | 1.28 | 1.31 |
| 26 | 3.236 | 0.14 | 0.55 | 8.29 | 8.49 | |
| 53 | 2.874 | 0.19 | 0.64 | 16.9 | 17.0 | |
| TiO2 | 271 | 2.021 | 0.60 | 1.50 | 88.7 | 90.5 |
| Al2O3 | 23 | 2.275 | 0.13 | 0.41 | 8.00 | 8.82 |
| 94 | 2.423 | 0.55 | 1.69 | 32.7 | 36.0 | |
| 235 | 2.709 | 1.21 | 3.81 | 80.2 | 86.6 | |
| CeO2 | 8 | 2.683 | 0.06 | 0.17 | 2.77 | 3.13 |
| 30 | 2.672 | 0.21 | 0.65 | 10.4 | 11.8 | |
| 152 | 2.598 | 0.76 | 2.38 | 51.3 | 54.3 | |
The upper respiratory tract (URT) starts at the nasal openings and ends at the beginning of the trachea. The lower respiratory tract (LRT) includes 22 airway generations and can be divided into the tracheo-bronchial (TB, trachea, bronchi, and bronchioles) region and the pulmonary (PUL, alveolar ducts, and sacs) region.