2012 Progress Report: Effects of Long-Term Exposure to Traffic-Derived Particles and Gases on Subclinical Measures of Cardiovascular Disease in a Multi-Ethnic Cohort

EPA Grant Number: R834796C005
Subproject: this is subproject number 005 , established and managed by the Center Director under grant R834796
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: University of Washington Center for Clean Air Research
Center Director: Vedal, Sverre
Title: Effects of Long-Term Exposure to Traffic-Derived Particles and Gases on Subclinical Measures of Cardiovascular Disease in a Multi-Ethnic Cohort
Investigators: Vedal, Sverre , Kaufman, Joel D. , Larson, Timothy V. , Sampson, Paul , Sheppard, Lianne (Elizabeth) A. , Szpiro, Adam , Yost, Michael
Institution: University of Washington
EPA Project Officer: Callan, Richard
Project Period: December 1, 2010 through November 30, 2015 (Extended to November 30, 2017)
Project Period Covered by this Report: December 1, 2011 through July 31,2012
RFA: Clean Air Research Centers (2009) RFA Text |  Recipients Lists
Research Category: Health Effects , Air


Project 5 has three primary objectives:

  1. Employ the small-scale gradient data acquired as part of the mobile monitoring campaign in Project 1, in conjunction with central fixed site data, regulatory monitoring data, and geographic covariates, to build a multi-pollutant exposure model for traffic-derived air pollutants. This model will incorporate complex spatial information on primary and secondary traffic-derived particles and gases.
  2. Develop and validate individual-level exposure estimates for traffic-derived air pollutants, integrating: i) the outdoor residential concentration estimates from the multi-pollutant model; ii) estimates of residential infiltration rates; iii) road class- and traffic condition-specific estimates of on-roadway concentrations; and iv) individual-level questionnaire-derived time-location information. These individual-level exposure estimates also will utilize personal monitoring data designed to clarify the in-transit component of total exposure.
  3. Estimate the effect of individual-level exposure to traffic-derived air pollution on subclinical cardiovascular disease using these exposure models. Health outcomes will include left ventricular myocardial mass as ascertained by MRI, arteriolar diameters as measured by retinal photography, coronary artery calcium as ascertained by CT, intima-medial thickness as measured by ultrasound, and DNA methylation.

Progress Summary:

Over the past year, a significant amount of planning has gone into Project 5. Project initiation has been delayed by the extension of MESA Exam 5. This exam recently has concluded, and we now have been able to begin to coordinate the field work portion of this project with the participating field centers at Wake Forest University and UCLA. The current plan is for these field activities to begin in January 2013 in Winston-Salem, followed quickly by a February sampling event in Los Angeles.

In each city, we will be visiting the residences of approximately 40 participants, and deploying indoor, outdoor, personal, and in-vehicle monitors at each location. We also will be providing each participant with a GPS data-logger to wear consistently throughout the 2-week sampling period, and will be asking them to complete time-location diaries. Based on the logistics inherent in this effort, we will be sending two teams of two technicians out for each sampling event (twice what we had originally proposed). We expect that these teams can each visit three homes per day.

The ideal situation would be for the sampling included in this project to overlap exactly with the 2-week sampling event occurring in Project 1. However, because we can sample only six homes per day, we will need to allow there to be a date mismatch of up to 3 days in either direction. Therefore, we will deploy samplers every day for a 7 day period, centered on the beginning of the Project 1 sampling. Therefore, although we had originally planned to include 72 participants per sampling event, we now plan to include 42 (6 per day for 7 days).

In addition to developing our plan to integrate with Project 1, we also have been working to develop our GPS data logger, which has been pilot tested by several staff members. This device has been developed to have sufficient battery life to track a participant for a full 2 weeks without requiring charging, and we currently are evaluating its spatial accuracy. In addition, we have been working to develop the technology for our in-vehicle sampling, as well as proximity monitors to allow identification of specifically when each participant is inside his/her home or in his/her car. We also have been developing the survey instruments we will use to collect self-reported time-location information.

Future Activities:

The next phase of this project will be to work with the field centers at Wake Forest University and UCLA to create subcontracts for the portion of this work that will employ field center staff, including participant recruitment and consent. These subcontracts are expected in Project Year 3. Once those subcontracts have been established, we will work with the field centers to submit materials to their Internal Review Boards for Human Subject approvals.

We also will be submitting a modification to add this work as an ancillary study to the already approved Human Subjects application (#26962). Currently, we anticipate including participants with the following characteristics: 1) previously consented to be contacted regarding personal and residential monitoring as part of MESA Air; 2) own and drive their own car as a primary mode of transportation; 3) intend to be spending their time primarily at their primary residence during the sampling period; 4) and are non-smokers. We intend to recruit participants specifically to represent those who report a range of time spent in transit, road types traveled, and traffic conditions experienced, based on their responses to the MESA Air questionnaires that they completed previously.

Journal Articles:

No journal articles submitted with this report: View all 29 publications for this subproject

Supplemental Keywords:

Cardiovascular disease, subclinical;, Health, Scientific Discipline, Air, ENVIRONMENTAL MANAGEMENT, Air Quality, air toxics, Health Risk Assessment, Risk Assessments, mobile sources, Risk Assessment, ambient air quality, particulate matter, atmospheric particulate matter, air pollutants, vehicle emissions, aerosol particles, motor vehicle emissions, air quality models, airway disease, bioavailability, motor vehicle exhaust, air pollution, particle exposure, atmospheric aerosols, ambient particle health effects, vascular dysfunction, cardiotoxicity, atmospheric chemistry, cardiovascular disease

Progress and Final Reports:

Original Abstract
  • 2011 Progress Report
  • 2013 Progress Report
  • 2014
  • 2015 Progress Report
  • 2016 Progress Report
  • Final Report

  • Main Center Abstract and Reports:

    R834796    University of Washington Center for Clean Air Research

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R834796C001 Exposure Mapping – Characterization of Gases and Particles for ExposureAssessment in Health Effects and Laboratory Studies
    R834796C002 Simulated Roadway Exposure Atmospheres for Laboratory Animal and Human Studies
    R834796C003 Cardiovascular Consequences of Immune Modification by Traffic-Related Emissions
    R834796C004 Vascular Response to Traffic-Derived Inhalation in Humans
    R834796C005 Effects of Long-Term Exposure to Traffic-Derived Particles and Gases on Subclinical Measures of Cardiovascular Disease in a Multi-Ethnic Cohort