Near-highway pollutants in motor vehicle exhaust: A review of epidemiologic evidence of cardiac and pulmonary health risks

Table 1 Summary of near-highway pollution gradients

Citation	Location	Highway traffic intensity^a	Pollutants measured^b	Observed Pollution Gradients
Shi et al. 1999 (6)	Birmingham, UK	30,000 veh/d	UFP + FP (10-10⁴ nm)	2–100 m ^c
Zhu et al. 2002 (8)	Los Angeles; Freeway 710	12,180 veh/h	UFP, CO, BC	17–300 m ^c
Zhu et al. 2002 (7)	Los Angeles; Freeway 405	13,900 veh/h	UFP, CO, BC	30–300 m ^c
Hitchins et al. 2002 (11)	Brisbane (Austr.)	2,130–3,400 veh/h	UFP + FP (15-2 × 10⁴ nm), PM_2.5	15–375 m ^c
Fischer et al. 2000 (13)	Amsterdam	<3,000–30,974 veh/d	PM_2.5, PM₁₀, PPAH, VOCs	NA
Roorda-Knape et al. 1998 (14)	Netherlands	80,000–152,000 veh/d	PM_2.5, PM₁₀, BC, VOCs, NO₂	15–330 m ^c
Janssen et al. 2001 (15)	Netherlands	40,000–170,000 veh/d	PM_2.5, VOCs, NO₂	< 400 m ^c
Morawska et al. 1999 (12)	Brisbane (Austr.)	NA	UFP	10–210 m ^c

^aAs defined in article cited (veh/d = vehicles per day; veh/h = vehicles per hour).
^bUFP = ultrafine particles; FP = fine particles; PM_2.5 = particles with aerodynamic diameter ≤ 2.5 um; PM₁₀ = particles with aerodynamic diameter ≤ 10 um; BC = black carbon; PPAH = particle-bound polycyclic aromatic hydrocarbons; VOCs = volatile organic compounds
^cPollutant measurements were made along a transect away from the highway
NA = not applicable; measurements were not made.

ISSN: 1476-069X