Skip to main content

Table 1 Descriptive statistics of ambient air pollutant concentrations in metropolitan Atlanta during May through October.a

From: Implications of different approaches for characterizing ambient air pollutant concentrations within the urban airshed for time-series studies and health benefits analyses

Pollutant Number of Monitors Number of Observations Central monitor Mean (IQR) Unweighted average Mean (IQR) Population-weighted average Mean (IQR)
8-h ozone, ppbb 5 2205 56.7 (26.4) 54.8 (25.0) 55.3 (22.6)
24-h PM10, μg/m3c 9 1563 29.4 (13.4) 29.7 (14.0) 27.4 (12.4)
24-h PM2.5, μg/m3d 11 1134 19.2 (9.8) 19.9 (9.1) 18.4 (8.7)
24-h PM2.5 sulfate, μg/m3d 6 980 6.3 (3.7) 5.8 (3.6) 5.8 (3.5)
24-h PM2.5 organic carbon, μg/m3d 6 1089 4.19 (1.92) 4.60 (2.45) 4.71 (2.71)
24-h PM2.5 elemental carbon, μg/m3d 6 1089 1.62 (0.91) 1.25 (0.68) 0.82 (0.53)
1-h nitrogen dioxide, ppbb 6 2190 42.0 (19.7) 27.7 (13.5) 22.0 (10.1)
1-h carbon monoxide, ppmb 3 1999 1.45 (0.83) 1.39 (0.92) 0.87 (0.46)
1-h sulfur dioxide, ppbb 5 2201 13.9 (13.0) 10.2 (7.7) 9.6 (7.6)
  1. Abbreviations: interquartile range (IQR), hour (h), parts per billion (ppb), micrograms per cubic meter (μg/m3), parts per million (ppm).
  2. aAmbient air pollutant concentrations are presented as three-day moving averages.
  3. bData begin on May 1, 1993.
  4. cData begin on May 1, 1996.
  5. dData begin on August 1, 1998.