Table 2 Exposure estimates based on personal sampling, land-use regression and ambient monitors
Estimated exposureMethodArithmetic mean (SD)Geometric mean (GSD)Min–MaxIQR
NO (ppb),Personal sampling*48.5 (50.5)36.7 (2.0)6.9–47437.5
n = 127LUR† home (monthly)27.0 (19.7)21.4 (2.0)3.6–14625.5
LUR home+work (monthly)28.0 (18.4)23.2 (1.9)6.0–13424.7
Ambient monitors IDW‡17.6 (14.5)13.9 (1.9)4.2–8313.0
NO2 (ppb),Personal sampling18.7 (9.2)16.9 (1.6)4.8–7611.1
n = 127LUR home (annual)§17.3 (3.3)16.9 (1.2)6.5–282.8
LUR home+work (annual)17.4 (2.9)17.2 (1.2)7.6–272.5
Ambient monitors IDW19.6 (4.0)19.2 (1.2)10.8–276.9
ABS (10−5 m−1),Personal sampling0.9 (0.4)0.8 (1.5)0.2–2.40.5
n = 120LUR home (annual)¶0.7 (0.3)0.7 (1.7)0.0–1.20.2
LUR home+work (annual)0.7 (0.2)0.7 (1.7)0.1–1.30.2
No monitor data
PM2.5 (μg/m3),Personal sampling**11.3 (6.6)10.0 (1.6)4.2–45.35.7
n = 124LUR home (annual)4.2 (1.5)4.2 (1.4)0.0–10.11.5
LUR home+work (annual)4.0 (1.3)3.7 (1.6)0.3–7.51.3
Ambient monitors IDW4.8 (1.3)4.6 (1.3)2.6–9.91.8
  • *One NO personal sample was below the limit of detection (LOD). All other samples were above their respective LODs.

  • †LUR surfaces as described in Henderson et al28 and that were developed based on road length metrics.

  • ‡IDW concentrations from the three closest monitoring stations.

  • §In the analyses, annual NO2 showed the strongest relationship to personal measurements (rather than monthly), so only annual results are reported in the descriptive tables.

  • ¶No monthly trend was applied to the absorbance estimates by design in the development of the LUR surface for this pollutant.

  • **Personal sampling for particulate was collected as PM2.2 not PM2.5; for simplicity, all tables and figures will refer to PM2.5 for all fine particulate sampling.

  • ABS, absorbance; IDW, inverse distance weighted; IQR, interquartile range; LUR, land-use regression.