TABLE 3.
RATE RATIOS AND 95% CONFIDENCE INTERVALS FOR QUINTILES OF THREE-DAY MOVING AVERAGE POPULATION-WEIGHTED AMBIENT AIR POLLUTANT CONCENTRATIONS
| Warm Season RR (95% CI)* | Cold Season RR (95% CI)* | |
|---|---|---|
| Ozone, ppb† | ||
| Q2 (26.3 to <38.7) | 1.002 (0.953–1.054) | 1.039 (0.998–1.081) |
| Q3 (38.7 to <51.5) | 1.016 (0.961–1.074) | 1.097 (1.037–1.161) |
| Q4 (51.5 to <67) | 1.061 (0.999–1.127) | 1.151 (1.065–1.243) |
| Q5 (67 to ≤147.5) | 1.111 (1.038–1.189) | 1.150 (1.013–1.306) |
| Nitrogen dioxide, ppb† | ||
| Q2 (28 to <37.1) | 1.033 (0.999–1.069) | 0.996 (0.964–1.030) |
| Q3 (37.1 to <46) | 1.040 (1.000–1.081) | 0.984 (0.950–1.020) |
| Q4 (46 to <57.1) | 1.087 (1.044–1.131) | 1.024 (0.985–1.064) |
| Q5 (57.1 to ≤181) | 1.087 (1.036–1.140) | 1.014 (0.973–1.056) |
| Carbon monoxide, ppm† | ||
| Q2 (0.70 to <1.01) | 1.019 (0.986–1.054) | 1.010 (0.977–1.045) |
| Q3 (1.01 to <1.05) | 1.046 (1.008–1.086) | 1.040 (1.005–1.076) |
| Q4 (1.05 to <2.30) | 1.097 (1.049–1.147) | 1.005 (0.969–1.042) |
| Q5 (2.30 to ≤7.70) | 1.112 (1.054–1.174) | 1.021 (0.981–1.064) |
| Sulfur dioxide, ppb† | ||
| Q2 (3.1 to <7) | 1.021 (0.988–1.055) | 0.968 (0.935–1.002) |
| Q3 (7 to <13) | 1.041 (1.007–1.077) | 0.998 (0.964–1.034) |
| Q4 (13 to <24.2) | 1.048 (1.010–1.087) | 0.982 (0.947–1.017) |
| Q5 (24.2 to ≤149) | 1.008 (0.967–1.051) | 0.987 (0.949–1.026) |
| PM10 (μg/m3)‡ | ||
| Q2 (16 to <21.9) | 1.014 (0.968–1.061) | 1.008 (0.978–1.038) |
| Q3 (21.9 to <28 | 1.029 (0.981–1.080) | 0.996 (0.963–1.030) |
| Q4 (28 to <36) | 1.027 (0.979–1.078) | 1.017 (0.977–1.059) |
| Q5 (36 to ≤98.4) | 1.059 (1.006–1.116) | 1.047 (0.991–1.106) |
| PM10–2.5 (μg/m3)§ | ||
| Q2 (5 to <7.1) | 0.975 (0.924–1.028) | 0.972 (0.930–1.012) |
| Q3 (7.1 to <9.3) | 0.986 (0.934–1.040) | 1.006 (0.960–1.054) |
| Q4 (9.3 to <12.3) | 0.964 (0.909–1.022) | 1.045 (0.996–1.097) |
| Q5 (12.3 to ≤50.4) | 1.005 (0.942–1.072) | 1.075 (1.015–1.139) |
| PM2.5 (μg/m3)§ | ||
| Q2 (10 to <13.7) | 0.993 (0.943–1.047) | 0.985 (0.952–1.019) |
| Q3 (13.7 to <17.6) | 1.008 (0.956–1.062) | 0.979 (0.943–1.017) |
| Q4 (17.6 to <23.8) | 1.018 (0.966–1.073) | 1.006 (0.960–1.049) |
| Q5 (23.8 to ≤65.8) | 1.052 (0.995–1.112) | 1.050 (0.997–1.106) |
| PM2.5 sulfate (μg/m3)§ | ||
| Q2 (2.2 to <3.3) | 1.032 (0.951–1.120) | 0.987 (0.950–1.025) |
| Q3 (3.3 to <4.6) | 1.048 (0.968–1.135) | 1.045 (0.998–1.094) |
| Q4 (4.6 to <7.2) | 1.061 (0.978–1.150) | 1.008 (0.944–1.077) |
| Q5 (7.2 to ≤21.9) | 1.082 (0.995–1.177) | 1.027 (0.931–1.133) |
| PM2.5 elemental carbon (μg/m3)§ | ||
| Q2 (0.78 to <1.13) | 0.981 (0.936–1.028) | 1.034 (0.994–1.076) |
| Q3 (1.13 to <1.55) | 1.023 (0.977–1.071) | 1.027 (0.984–1.072) |
| Q4 (1.55 to <2.25) | 1.050 (1.004–1.107) | 1.014 (0.971–1.058) |
| Q5 (2.25 to ≤11.89) | 1.056 (1.000–1.115) | 1.039 (0.990–1.091) |
| PM2.5 organic carbon (μg/m3)§ | ||
| Q2 (2.54 to <3.41) | 1.024 (0.976–1.073) | 0.983 (0.942–1.025) |
| Q3 (3.41 to <4.32) | 1.070 (1.020–1.122) | 1.028 (0.983–1.075) |
| Q4 (4.32 to <5.82) | 1.078 (1.024–1.135) | 0.993 (0.950–1.038) |
| Q5 (5.82 to ≤25.93) | 1.065 (1.006–1.128) | 1.017 (0.972–1.063) |
| PM2.5 water-soluble metals (μg/m3)§ | ||
| Q2 (0.0123 to <0.0195) | 1.026 (0.946–1.112) | 0.992 (0.953–1.032) |
| Q3 (0.0195 to <0.0276) | 1.081 (0.999–1.170) | 1.004 (0.958–1.053) |
| Q4 (0.0276 to <0.0436) | 1.113 (1.026–1.206) | 1.036 (0.978–1.096) |
| Q5 (0.0436 to ≤0.202) | 1.119 (1.028–1.218) | 1.009 (0.934–1.090) |
Definition of abbreviations: CI = confidence interval; PM = particulate matter less than 10, 2.5, or 10–2.5 μm in aerodynamic diameter; RR = rate ratio.
Bold typeface indicates confidence intervals that do not include the null value.
*
Relative to the first quintile (concentrations less than the lower bound of the second quintile).
†
Measurements available January 1993 to December 2004.
‡
Measurements available August 1998 to December 2004.
§
Measurements available August 1998 to December 2004.