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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 (28.8 to < 39.0) 1.012 (0.957, 1.071) 0.994 (0.963, 1.026)

 Q3 (39.0 to < 49.2) 1.040 (0.979, 1.105) 1.055 (1.008, 1.105)

 Q4 (49.2 to < 61.1) 1.056 (0.989, 1.127) 1.138 (1.069, 1.211)

 Q5 (61.1 to ≤ 107.4) 1.106 (1.030, 1.187) 1.136 (1.022, 1.262)

Nitrogen dioxide (ppb)†

 Q2 (16.7 to < 20.6) 1.047 (1.011, 1.084) 1.045 (1.005, 1.086)

 Q3 (20.6 to < 24.3) 1.057 (1.019, 1.096) 1.035 (0.994, 1.077)

 Q4 (24.3 to < 29.3) 1.066 (1.024, 1.110) 1.018 (0.976, 1.061)

 Q5 (29.3 to ≤ 55.2) 1.098 (1.048, 1.151) 1.035 (0.990, 1.082)

Carbon monoxide (ppm)†

 Q2 (0.58 to < 0.75) 1.013 (0.979, 1.048) 0.999 (0.996, 1.033)

 Q3 (0.75 to < 0.94) 1.084 (1.043, 1.127) 1.043 (1.006, 1.080)

 Q4 (0.94 to < 1.23) 1.058 (1.010, 1.107) 1.000 (0.964, 1.038)

 Q5 (1.23 to ≤ 2.81) 1.130 (1.067, 1.196) 1.015 (0.974, 1.058)

Sulfur dioxide (ppb)†

 Q2 (5.1 to < 7.9) 1.001 (0.970, 1.034) 0.980 (0.945, 1.017)

 Q3 (7.9 to < 11.0) 1.035 (1.001, 1.070) 1.008 (0.973, 1.045)

 Q4 (11.0 to < 15.8) 1.032 (0.994, 1.070) 0.997 (0.960, 1.035)

 Q5 (15.8 to ≤ 49.5) 1.033 (0.987, 1.082) 1.000 (0.960, 1.042)

PM10 (μg/m3)†

 Q2 (15.9 to < 20.4) 1.022 (0.974, 1.072) 0.991 (0.961, 1.022)

 Q3 (20.4 to < 25.0) 1.016 (0.968, 1.066) 0.993 (0.959, 1.028)

 Q4 (25.0 to < 31.2) 1.014 (0.966, 1.064) 1.021 (0.981, 1.062)

 Q5 (32.2 to ≤ 73.8) 1.067 (1.013, 1.124) 1.052 (1.000, 1.107)

PM10-2.5 (μg/m3) 

 Q2 (5.9 to < 7.6) 0.975 (0.924, 1.028) 0.972 (0.930, 1.012)

 Q3 (7.6 to < 9.5) 0.986 (0.934, 1.040) 1.006 (0.960, 1.054)

 Q4 (9.5 to < 11.7) 0.964 (0.909, 1.022) 1.045 (0.996, 1.097)

 Q5 (11.7 to ≤ 31.8) 1.005 (0.942, 1.072) 1.075 (1.015, 1.139)

PM2.5 (μg/m3)‡

 Q2 (11.1 to < 14.0) 0.986 (0.937, 1.038) 1.003 (0.971, 1.037)

 Q3 (14.0 to < 16.6) 1.027 (0.976, 1.080) 0.992 (0.956, 1.030)

 Q4 (16.6 to < 21.1) 1.020 (0.970, 1.073) 1.017 (0.974, 1.062)

 Q5 (21.1 to ≤ 53.7) 1.044 (0.989, 1.103) 1.045 (0.986, 1.108)

PM2.5 sulfate (μg/m3)‡

 Q2 (2.4 to < 3.4) 0.974 (0.908, 1.044) 0.988 (0.955, 1.022)

 Q3 (3.4 to < 4.5) 0.974 (0.913, 1.040) 1.031 (0.992, 1.072)

 Q4 (4.5 to < 6.4) 1.022 (0.956, 1.093) 1.016 (0.963, 1.072)

 Q5 (6.4 to ≤ 18.3) 1.026 (0.955, 1.101) 0.997 (0.922, 1.077)

PM2.5 elemental carbon (μg/m3)‡

 Q2 (0.45 to < 0.67) 1.036 (0.993, 1.082) 1.001 (0.963, 1.041)

 Q3 (0.67 to < 0.88) 1.027 (0.979, 1.077) 1.021 (0.977, 1.068)

 Q4 (0.88 to < 1.18) 1.088 (1.030, 1.150) 1.004 (0.957, 1.053)

 Q5 (1.18 to ≤ 4.85) 1.109 (1.043, 1.180) 1.003 (0.952, 1.056)

PM2.5 organic carbon (μg/m3)‡

 Q2 (2.9 to < 3.8) 1.026 (0.978, 1.076) 1.010 (0.971, 1.052)

 Q3 (3.8 to < 4.9) 1.105 (1.054, 1.158) 1.003 (0.961, 1.048)

 Q4 (4.9 to < 6.4) 1.121 (1.066, 1.178) 0.987 (0.945, 1.032)

 Q5 (6.4 to ≤ 37.8) 1.104 (1.045, 1.165) 1.011 (0.966, 1.058)

PM2.5 water-soluble metals (μg/m3)‡

 Q2 (0.0149 to < 0.0213) 1.026 (0.946, 1.112) 0.992 (0.953, 1.032)

 Q3 (0.0213 to < 0.0295) 1.081 (0.999, 1.170) 1.004 (0.958, 1.053)

 Q4 (0.0295 to < 0.0430) 1.113 (1.026, 1.206) 1.036 (0.978, 1.096)

 Q5 (0.0430 to ≤ 0.1717) 1.119 (1.028, 1.218) 1.009 (0.934, 1.090)

*Relative to the first quintile (concentrations less than the lower bound of the second quintile)

† Measurements available January, 1993 – December, 2004

‡ Measurements available August, 1998 – December, 2004

 Measurements available January, 1996 – December, 2004