Pollutant | Mean | IQR | All seasons | Season | ||||
---|---|---|---|---|---|---|---|---|
 |  |  |  |  | October to March | April to September | ||
 |  |  | OR | 95% C.I. | OR | 95% C.I. | OR | 95% C.I. |
SO2 | Same day | 3.0 | 0.96 | 0.88–1.06 | 0.93 | 0.82–1.05 | 1.01 | 0.87–1.17 |
 | 1-day lag |  | 1.01 | 0.92–1.11 | 0.99 | 0.88–1.12 | 1.03 | 0.89–1.19 |
 | 3-day average |  | 1.03 | 0.90–1.18 | 0.99 | 0.84–1.18 | 1.09 | 0.87–1.38 |
 | 5-day average |  | 1.06 | 0.90–1.24 | 1.04 | 0.86–1.27 | 1.07 | 0.81–1.42 |
NO2 | Same day | 13.5 | 1.00 | 0.91–1.10 | 0.96 | 0.86–1.07 | 1.14 | 0.94–1.37 |
 | 1-day lag |  | 1.09 | 0.99–1.20 | 1.08 | 0.97–1.21 | 1.13 | 0.93–1.36 |
 | 3-day average |  | 1.13 | 1.00–1.27 | 1.07 | 0.93–1.24 | 1.33 | 1.03–1.70 |
 | 5-day average |  | 1.20 | 1.04–1.38 | 1.15 | 0.98–1.35 | 1.37 | 1.02–1.84 |
CO | Same day | 0.5 | 0.96 | 0.89–1.03 | 0.94 | 0.87–1.01 | 1.11 | 0.91–1.35 |
 | 1-day lag |  | 1.01 | 0.94–1.09 | 1.00 | 0.93–1.08 | 1.12 | 0.91–1.37 |
 | 3-day average |  | 1.00 | 0.91–1.10 | 0.97 | 0.88–1.07 | 1.28 | 0.96–1.69 |
 | 5-day average |  | 1.08 | 0.97–1.20 | 1.04 | 0.93–1.16 | 1.54 | 1.09–2.17 |
O3 | Same day | 18.0 | 1.08 | 0.96–1.23 | 1.07 | 0.90–1.29 | 1.10 | 0.92–1.32 |
 | 1-day lag |  | 0.98 | 0.87–1.10 | 0.97 | 0.82–1.16 | 0.99 | 0.84–1.16 |
 | 3-day average |  | 1.02 | 0.87–1.19 | 1.00 | 0.79–1.27 | 1.04 | 0.84–1.30 |
 | 5-day average |  | 1.01 | 0.85–1.20 | 1.04 | 0.80–1.36 | 0.99 | 0.78–1.25 |
PM2.5 ‡ | Same day | 6.3 | 1.12 | 1.01–1.23 | 1.06 | 0.92–1.22 | 1.19 | 1.02–1.40 |
 | 1-day lag |  | 1.06 | 0.96–1.16 | 1.02 | 0.89–1.17 | 1.08 | 0.94–1.23 |
 | 3-day average |  | 1.11 | 0.98–1.26 | 1.05 | 0.87–1.26 | 1.16 | 0.96–1.41 |
 | 5-day average |  | 1.13 | 0.97–1.30 | 1.16 | 0.94–1.44 | 1.07 | 0.86–1.33 |
PM10 ‡ | Same day | 16.0 | 1.06 | 0.95–1.17 | 0.96 | 0.82–1.12 | 1.17 | 1.00–1.36 |
 | 1-day lag |  | 1.06 | 0.96–1.17 | 1.03 | 0.90–1.18 | 1.10 | 0.95–1.26 |
 | 3-day average |  | 1.04 | 0.92–1.18 | 0.96 | 0.80–1.14 | 1.14 | 0.95–1.37 |
 | 5-day average |  | 1.07 | 0.92–1.23 | 1.08 | 0.89–1.32 | 1.06 | 0.86–1.30 |