Grantee Research Project Results
2003 Progress Report: Exposure to Vehicular Pollutants and Respiratory Health
EPA Grant Number: R827352C007Subproject: this is subproject number 007 , established and managed by the Center Director under grant R827352
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: UC Berkeley/Stanford Children’s Environment Health Center
Center Director: Tager, Ira
Title: Exposure to Vehicular Pollutants and Respiratory Health
Investigators: McConnell, Rob Scot , Gilliland, Frank D. , Avol, Edward L. , Peters, John M. , Lurmann, Fred , Gauderman, William
Current Investigators: McConnell, Rob Scot , Avol, Edward L. , Lurmann, Fred , Gauderman, William
Institution: University of Southern California
EPA Project Officer: Chung, Serena
Project Period: June 1, 1999 through May 31, 2005 (Extended to May 31, 2006)
Project Period Covered by this Report: June 1, 2002 through May 31, 2003
RFA: Airborne Particulate Matter (PM) Centers (1999) RFA Text | Recipients Lists
Research Category: Air Quality and Air Toxics , Particulate Matter , Air
Objective:
The overall objective of this research project is to examine the relationship between estimates of exposure to traffic-related pollutants, derived from CALINE4, and the primary respiratory outcomes in the Children’s Health Study (CHS). During the past year, we have focused on: (1) prevalence of lifetime asthma at entry into the study; (2) incidence of asthma during followup; (3) lung function at study entry and its growth during followup; (4) school absence and traffic (a new outcome of interest for traffic); (5) chronic asthma exacerbation associated with yearly variation in particulate metrics; and (6) NO in fresh traffic exhaust may reduce exposures to ozone; therefore, the effect of traffic density within a community may vary depending on ambient ozone levels.
This is one research project of the Southern California Particle Center and Supersite (SCPCS). The progress of the other projects is reported separately (see reports for R827352, R827352C001 through R827352C011, and R827352C013 through R827352C021).
Progress Summary:
Our approach has been to geocode addresses of residences and schools and then to assign traffic exposures to these addresses, based on traffic estimates available from Caltrans. Using modifications of statistical modeling strategies we have developed for the CHS, the effect of traffic exposure on lung function and asthma prevalence and incidence has been examined. In reports from previous years, we presented data suggesting that the effect of traffic may be an early life effect of residential proximity to freeways. We have examined the association of residential and school proximity to heavy traffic corridors with lung function, lung function growth, asthma prevalence and incidence, and school absence. We have relied heavily on the results of Fred Lurmann’s efforts to better model particulate matter (PM) and other exposures resulting from residential and school proximity to traffic. This year, we have concentrated on consolidating this work.
Aim 1: Effect of Traffic on Asthma Prevalence
We have completed our analyses of lifetime asthma at study entry and traffic-related pollutant exposure. We observed large risks associated with measured home NO2 and with residential distance to a freeway (manuscript in review, 2004). There were no associations with other CALINE4 particulate metrics. In a preliminary examination of risks associated with early life asthma in younger children (5-6 years old) in Long Beach, we also are seeing large risks associated with traffic-related pollution, in spite of relatively small size. Among children in the upper decile of traffic density within 150 m and among children with more than 20,000 average annual daily traffic counts within 50 m of the home, we see greater than fivefold increased risks of lifetime asthma. Analyses are ongoing.
Aim 2: Effect of Traffic on Asthma Incidence and Estimating Competing Risks for Ozone and PM
We have completed analyses to evaluate systematically how ozone varies within communities based on traffic patterns. We used a sample of homes for which ozone was measured simultaneously at the home and the central site monitor as part of a previous study (Avol, et al., 1998). Using the proposed prediction model from this manuscript, we have observed large risks of new onset asthma associated with within-community variability in ozone exposure. We also examined residential distance to a freeway because this metric (indicative of particulate exposure) was associated with lifetime asthma at study entry. There was no significant association with freeway distance by itself, but if we adjusted for the effect of ozone, there was a significant association with freeway distance. We believe that because distance to a freeway and ozone are inversely correlated, an effect of the particulate exposure from freeways was only observed after accounting for the competing risk of asthma associated with ozone. The effect of ozone is unlikely to be explained by confounding because the effect was unchanged in models controlling for demographic characteristics, income, education, indicators of access to care, and indoor exposures. In addition, the effect was modified by family history of asthma (bigger risk of asthma among those children with no family history), and the effect of within-community variability in ozone is larger in communities with higher average background concentrations of ozone. These results are compatible with previous associations of incident asthma with ozone that we observed in the CHS, effects that also were larger in children without an atopic history (McConnell, et al., 2002). They also are compatible with recent toxicologic evidence that air pollutant exposure causes asthma (Schelegle, et al., 2003; Miller, et al., 2003; Larson, et al., 2003). A manuscript is in preparation.
Aim 3: Effect of Traffic on Lung Function and Lung Function Growth
We have examined the association of lung function deficits at study entry with a novel Bayesian estimator of NO2 exposure at homes. Local variation in NO2 within communities may be considered a surrogate of particulate exposure associated with fresh traffic emissions. In addition, lung function growth curves for 8 years of followup of the CHS have become available recently, and preliminary analyses suggest that these are associated with traffic-related particulate pollutants derived from CALINE4 as well as with background pollution measured at the central site monitor in each community.
Aim 4: School Absence and Traffic
School absences are an outcome not proposed for study in this year’s work plan, but we have observed strong associations with CALINE4-derived traffic metrics and distance to a freeway. The effects were observed exclusively among children with asthma. A manuscript is in preparation.
Aim 5: Chronic Asthma Exacerbation is Associated With Yearly Variation in Central Site Particulate Metrics
Studies of the toxicology and chemistry of PM by other SCPCS coinvestigators suggest that organic carbon (OC) may be more biologically active than other PM components. Pollutants modeled from traffic estimate spatial variation in pollution within communities. An alternative approach to evaluating within-community variability in pollutant exposure is to examine the effect of the temporal variation from year to year in the average ambient pollutants measured at the central monitoring sites within each community. The association with OC is strong and robust to confounding by other particulate pollutants.
Progress and Results to Date
- Proximity to high-traffic corridors in early life is associated with asthma before school entry.
- In later childhood, it is possible that there are competing exposures to ozone and traffic-related pollutants that are involved in asthma pathogenesis.
- School absence is associated with traffic-related air pollution at home and school among children with asthma.
- Yearly variation in OC is associated strongly with bronchitis among children with asthma.
- Lung function and lung function growth are associated with traffic-related air pollution estimated both at the home and at the central site monitor.
We have focused on traffic as a source of particulate emissions likely to cause these health effects. Because particulate exposure is expensive to measure at multiple sites within communities, however, we have relied on distance to major roadways and samples of NO2 at homes as surrogates for particulate exposure. This is a limitation we will address in Year 6 of the project.
Future Activities:
The case-control study of early life asthma using time resolved nephelometry, PM10, PM 2.5, and PM0.25 measured at homes in Long Beach has been reviewed and approved by the U.S. Environmental Protection Agency This study will address a limitation to our studies to date that have relied on NO2 and other surrogates for particulate exposure.
References:
Avol EL, Navidi WC, Colome SD. Modeling ozone levels in and around Southern California homes. Environmental Science and Technology 1998;32:463-468.
Larson SD, Schelegle ES, Walby WF, Gershwin LJ, Fanuccihi MV, Evans MJ, Joad JP, Tarkington BK, Hyde DM, Plopper CG. Postnatal remodeling of the neural components of the epithelial-mesenchymal trophic unit in the proximal airways of infant rhesus monkeys exposed to ozone and allergen. Toxicology and Applied Pharmacology 2004;194(3):211-220.
Miller LA, Hyde DM, Gershwin LJ, Schelegle ES, Fanucchi MV, Evans MJ, Gerriets JE, Putney LF, Stovall MY, Tyler NK, Usachenko JL, Plopper CG. The effect of house dust mite aeroallergen and air pollutant exposures during infancy. Chest 2003;123(S3):434S.
Schelegle ES, Miller LA, Gershwin LJ, Fanucchi MV, Van Winkle LS, Gerriets JE, Walby WF, Mitchell V, Tarkington BK, Wong VJ, et al. Repeated episodes of ozone inhalation amplifies the effects of allergen sensitization and inhalation on airway immune and structural development in rhesus monkeys. Toxicology and Applied Pharmacology 2003;191(1):74-85.
Journal Articles:
No journal articles submitted with this report: View all 7 publications for this subprojectSupplemental Keywords:
particulate matter, PM, quinones, polycyclic aromatic hydrocarbons, PAHs, aldehydes, ketones, metals, allergic airway disease, human exposure studies, asthma, cardiovascular effects, aerosol sampling, atmospheric aerosol, environmental monitoring, environmental statistics, California, CA, acute exposure, aerosols, air pollution, air quality, air toxics, airway disease, allergen, allergic response, ambient aerosol, assessment of exposure, asthma triggers, atmospheric chemistry, bioaerosols, biological response, childhood respiratory disease, children, dosimetry, environmental hazard exposures, environmental health hazard, environmental triggers, environmentally caused disease, epidemiology, exposure assessment, health effects, home, household, human exposure, human health effects, indoor air quality, inhaled particles, lead, outdoor air, particle concentrator, particle transport, particulate exposure, particulates, sensitive populations, toxicology, toxics,, RFA, Scientific Discipline, Air, Geographic Area, HUMAN HEALTH, particulate matter, Environmental Chemistry, Health Risk Assessment, Air Pollutants, State, mobile sources, Health Effects, Environmental Monitoring, engine exhaust, ambient aerosol, asthma, motor vehicle emissions, epidemiology, human health effects, quinones, automotive emissions, particulate emissions, automobiles, automotive exhaust, PAH, air pollution, children, human exposure, PM characteristics, California (CA), allergens, indoor air quality, aerosols, atmospheric chemistryRelevant Websites:
Progress and Final Reports:
Original AbstractMain Center Abstract and Reports:
R827352 UC Berkeley/Stanford Children’s Environment Health Center Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R827352C001 The Chemical Toxicology of Particulate Matter
R827352C002 Pro-inflammatory and the Pro-oxidative Effects of Diesel Exhaust Particulate in Vivo and in Vitro
R827352C003 Measurement of the “Effective” Surface Area of Ultrafine and Accumulation Mode PM (Pilot Project)
R827352C004 Effect of Exposure to Freeways with Heavy Diesel Traffic and Gasoline Traffic on Asthma Mouse Model
R827352C005 Effects of Exposure to Fine and Ultrafine Concentrated Ambient Particles near a Heavily Trafficked Freeway in Geriatric Rats (Pilot Project)
R827352C006 Relationship Between Ultrafine Particle Size Distribution and Distance From Highways
R827352C007 Exposure to Vehicular Pollutants and Respiratory Health
R827352C008 Traffic Density and Human Reproductive Health
R827352C009 The Role of Quinones, Aldehydes, Polycyclic Aromatic Hydrocarbons, and other Atmospheric Transformation Products on Chronic Health Effects in Children
R827352C010 Novel Method for Measurement of Acrolein in Aerosols
R827352C011 Off-Line Sampling of Exhaled Nitric Oxide in Respiratory Health Surveys
R827352C012 Controlled Human Exposure Studies with Concentrated PM
R827352C013 Particle Size Distributions of Polycyclic Aromatic Hydrocarbons in the LAB
R827352C014 Physical and Chemical Characteristics of PM in the LAB (Source Receptor Study)
R827352C015 Exposure Assessment and Airshed Modeling Applications in Support of SCPC and CHS Projects
R827352C016 Particle Dosimetry
R827352C017 Conduct Research and Monitoring That Contributes to a Better Understanding of the Measurement, Sources, Size Distribution, Chemical Composition, Physical State, Spatial and Temporal Variability, and Health Effects of Suspended PM in the Los Angeles Basin (LAB)
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.
Project Research Results
- Final Report
- 2004 Progress Report
- 2002 Progress Report
- 2001 Progress Report
- 2000
- 1999
- Original Abstract
7 journal articles for this subproject
Main Center: R827352
150 publications for this center
149 journal articles for this center