Table 2 Distribution of daily pollution concentrations from 2004 to 2010 and reported as median (25^th–75^th percentiles)

O₃ (ppb)

21.7 (15.0–28.3)

19.3 (13.3–25.7)

23.7 (17.5–30.9)

0.2

SO₂ (ppb)

1.0 (0.9–1.8)

1.0 (1.0–2.0)

1.1 (0.8–1.6)

<0.001

CO (ppm)

0.3 (0.2–0.4)

0.4 (0.3–0.4)

0.3 (0.2–0.4)

<0.001

NO₂ (ppb)

12.7 (7.6–19.0)

17.3 (13.0–23.5)

7.9 (5.6–12.1)

<0.001

PM_2.5 (μg/m³)

5.3 (3.5–7.7)

6.0 (4.3–8.7)

4.6 (3.1–6.6)

0.2

PM₁₀ (μg/m³)

18.1 (13.0–27.0)

22.0 (15.0–32.0)

15.8 (12.0–21.8)

<0.001