Residential traffic and children's respiratory health.
BACKGROUND
Living near traffic has been associated with asthma and other respiratory symptoms. Most studies, however, have been conducted in areas with high background levels of ambient air pollution, making it challenging to isolate an independent effect of traffic. Additionally, most investigations have used surrogates of exposure, and few have measured traffic pollutants directly as part of the study.


OBJECTIVE
We conducted a cross-sectional study of current asthma and other respiratory symptoms in children (n = 1,080) living at varying distances from high-traffic roads in the San Francisco Bay Area, California, a highly urbanized region characterized by good regional air quality due to coastal breezes.


METHODS
We obtained health information and home environmental factors by parental questionnaire. We assessed exposure with several measures of residential proximity to traffic calculated using geographic information systems, including traffic within a given radius and distance to major roads. We also measured traffic-related pollutants (nitrogen oxides and nitrogen dioxide) for a subset of households to determine how well traffic metrics correlated with measured traffic pollutants.


RESULTS
Using multivariate logistic regression analyses, we found associations between current asthma and residential proximity to traffic. For several traffic metrics, children whose residences were in the highest quintile of exposure had approximately twice the adjusted odds of current asthma (i.e., asthma episode in the preceeding 12 months) compared with children whose residences were within the lowest quintile. The highest risks were among those living within 75 m of a freeway/highway. Most traffic metrics correlated moderately well with actual pollutant measurements.


CONCLUSIONS
Our findings provide evidence that even in an area with good regional air quality, proximity to traffic is associated with adverse respiratory health effects in children.
Kim
Janice J
JJ
Office of Environmental Health Hazard Assessment, Air Pollution Epidemiology Section, Oakland, California, USA.
Huen
Karen
K
Adams
Sara
S
Smorodinsky
Svetlana
S
Hoats
Abby
A
Malig
Brian
B
Lipsett
Michael
M
Ostro
Bart
B
D000393:Air Pollutants / Q000633:toxicity*; D002648:Child; D003430:Cross-Sectional Studies; D006801:Humans; D015999:Multivariate Analysis; D012129:Respiratory Function Tests; D001335:Vehicle Emissions
D000393:Air Pollutants; D001335:Vehicle Emissions
Eur Respir J. 2007 May;29(5):879-88
17251230
Lancet. 2002 Oct 19;360(9341):1203-9
12401246
Epidemiology. 2003 Nov;14(6):728-36
14569190
Occup Environ Med. 2008 Sep;65(9):579-86
18070798
Am J Respir Crit Care Med. 2004 Sep 1;170(5):520-6
15184208
Sci Total Environ. 2006 Sep 15;368(2-3):565-73
16650461
Respir Med. 2002 Nov;96(11):907-17
12418589
Eur Respir J. 2003 Jun;21(6):956-63
12797488
J Expo Anal Environ Epidemiol. 2003 May;13(3):240-6
12743618
Environ Health Perspect. 2003 Sep;111(12):1512-8
12948892
Environ Health Perspect. 2002 Aug;110 Suppl 4:573-89
12194890
Environ Res. 2002 Feb;88(2):73-81
11908931
Epidemiology. 1997 May;8(3):298-303
9115026
Environ Health Perspect. 2006 May;114(5):766-72
16675435
J Expo Sci Environ Epidemiol. 2006 Jan;16(1):49-55
16007113
Epidemiology. 2005 Nov;16(6):737-43
16222162
Environ Health Perspect. 2003 Feb;111(2):207-16
12573907
J Air Waste Manag Assoc. 2002 Sep;52(9):1032-42
12269664
J Allergy Clin Immunol. 2005 Feb;115(2):221-8; quiz 229
15696072
Environ Health Perspect. 1999 Sep;107(9):761-7
10464078
Am J Respir Crit Care Med. 2001 Dec 15;164(12):2177-80
11751183