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 | 1.00 | 0.95–1.05 | 0.98 | 0.92–1.05 | 1.01 | 0.94–1.08 |
 | 1-day lag |  | 0.95 | 0.90–1.00 | 0.93 | 0.87–0.99 | 0.95 | 0.89–1.03 |
 | 3-day average |  | 0.97 | 0.90–1.04 | 0.93 | 0.85–1.02 | 0.99 | 0.89–1.11 |
 | 5-day average |  | 0.96 | 0.89–1.04 | 0.91 | 0.82–1.02 | 0.99 | 0.87–1.12 |
NO2 | Same day | 13.5 | 1.00 | 0.95–1.05 | 0.96 | 0.91–1.02 | 1.08 | 0.99–1.18 |
 | 1-day lag |  | 1.04 | 0.99–1.09 | 0.96 | 0.90–1.02 | 1.24 | 1.13–1.35 |
 | 3-day average |  | 1.05 | 0.98–1.12 | 0.95 | 0.88–1.02 | 1.32 | 1.18–1.48 |
 | 5-day average |  | 1.08 | 1.00–1.16 | 0.93 | 0.85–1.01 | 1.50 | 1.31–1.71 |
CO | Same day | 0.5 | 0.99 | 0.95–1.03 | 0.97 | 0.93–1.01 | 1.06 | 0.97–1.15 |
 | 1-day lag |  | 1.02 | 0.98–1.05 | 0.99 | 0.95–1.03 | 1.14 | 1.04–1.25 |
 | 3-day average |  | 1.02 | 0.98–1.07 | 0.98 | 0.93–1.03 | 1.25 | 1.11–1.42 |
 | 5-day average |  | 1.04 | 0.98–1.10 | 0.97 | 0.91–1.03 | 1.48 | 1.27–1.72 |
O3 (Max) | Same day | 18.0 | 1.00 | 0.94–1.07 | 1.04 | 0.94–1.14 | 1.02 | 0.93–1.12 |
 | 1-day lag |  | 1.03 | 0.97–1.10 | 1.08 | 0.98–1.18 | 1.05 | 0.97–1.14 |
 | 3-day average |  | 1.06 | 0.97–1.14 | 1.12 | 0.99–1.27 | 1.10 | 0.98–1.22 |
 | 5-day average |  | 1.06 | 0.97–1.15 | 1.16 | 1.01–1.34 | 1.06 | 0.94–1.19 |
PM2.5 ‡ | Same day | 6.3 | 1.02 | 0.96–1.07 | 1.02 | 0.94–1.11 | 1.06 | 0.99–1.14 |
 | 1-day lag |  | 1.02 | 0.97–1.08 | 0.98 | 0.91–1.07 | 1.08 | 1.01–1.16 |
 | 3-day average |  | 1.04 | 0.98–1.12 | 1.00 | 0.91–1.11 | 1.15 | 1.05–1.26 |
 | 5-day average |  | 1.03 | 0.95–1.11 | 0.95 | 0.84–1.07 | 1.16 | 1.04–1.28 |
PM10 ‡ | Same day | 16.0 | 1.05 | 0.99–1.10 | 1.04 | 0.95–1.13 | 1.10 | 1.02–1.18 |
 | 1-day lag |  | 1.03 | 0.97–1.08 | 1.00 | 0.92–1.09 | 1.07 | 1.00–1.15 |
 | 3-day average |  | 1.07 | 1.00–1.14 | 1.02 | 0.92–1.13 | 1.14 | 1.04–1.26 |
 | 5-day average |  | 1.07 | 0.99–1.16 | 1.00 | 0.89–1.13 | 1.16 | 1.05–1.28 |