Table 3.
Distributions of PM2.5 and Proximity to a Major Roadway
| Median (IQR) or n [%] | Range (min, max) | Range (5th to 95th) | |
|---|---|---|---|
| 2003 Annual average PM2.5, μg/m3 | 10.7 (1.5) | 2.9–26.7 | 8.3–12.7 |
| Proximity to Major Roadway, m | 195.4 (342.8) | 0.01–999.7 | 7.1–804.9 |
| Residential Proximity in Categories, m | |||
| <50 | 1186 [23] | ||
| 50 to <100 | 541 [10] | ||
| 100 to <200 | 912 [18] | ||
| 200 to <400 | 1252 [24] | ||
| 400 to ≤1000 | 1316 [25] | ||
| Preceding Day PM2.5, μg/m3*(n=3,921) | 8.3 (6.2) | 0.9–75.9 | 3.5–21.1 |
| Preceding Day Black Carbon, μg/m3* (n=3,923) | 0.6 (0.5) | 0.1–4.2 | 0.3–1.5 |
| Preceding Day Particle Number, particles/cm3* (n=3,499) | 19,234 (15,000) | 3,791–63,866 | 7,983–40,771 |
| Preceding Day Sulfate, μg/m3* (n=3,589) | 2.4 (2.5) | 0.002–27.9 | 0.9–8.6 |
| Preceding Day NOx, ppm* (n=3,927) | 0.03 (0.02) | 0.006–0.17 | 0.02–0.07 |
| Preceding Day Ozone, ppm* (n=3,927) | 0.02 (0.02) | 0.001–0.09 | 0.01–0.05 |
| Preceding Day Temperature, °C | 10.5 (15.2) | −18.3–31.0 | −5.1–25.0 |
| Preceding Day Relative Humidity, % | 66 (26) | 21–99 | 40–92 |
*
For subpopulation living within 50 km from the central site monitor with non-missing pollutant data for days preceding examination cycle.