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Effects of outdoor air pollutants on asthma outcomes if legal concentrations are exceeded.
| Pollutant | Concentration μg/m3 | Asthma Symptoms | Exacerbations | Hospitalizations | Lung Function |
|---|---|---|---|---|---|
| O3 | 100 (8-h mean) |
- | ↑ | ↑ | ↓ |
| NO2 | 200 (1-h mean) |
↑ | ↑ | ↑ | ↓ |
| CO | 30 (1-h mean) |
- | ↑ | - | - |
| SO2 | 20 (24-h mean) |
↑ | ↑ | ↑ | ↓ |
| PM2.5 | 10 (annual mean) 25 (24-h mean) |
↑ | ↑ | ↑ | ↓ |
| PM10 | 20 (annual mean) 50 (24-h mean) |
↑ | ↑ | ↑ | ↓ |
