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Background value of atmospheric dust concentration (pc/L)
| Place | Full size | Above 0.5 μm | Above 0.3 μm | Above 5 μm | Pollen | Virus | Bacterium | Mould | Spore |
|---|---|---|---|---|---|---|---|---|---|
| Ocean | 210,000 | 2,500 | 7,500 | 28 | – | – | – | – | – |
| Stratosphere | |||||||||
| 10 km | 35,000 | 20 | 55 | – | 0.1 | – | (0.5–100) × 10−3 | 0.1–10 | 0–100 |
