2002 Progress Report: Relationship Between Ultrafine Particle Size Distribution and Distance From Highways

EPA Grant Number: R827352C006
Subproject: this is subproject number 006 , 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: Southern California Particle Center and Supersite
Center Director: Froines, John R.
Title: Relationship Between Ultrafine Particle Size Distribution and Distance From Highways
Investigators: Hinds, William C. , Sioutas, Constantinos , Zhu, Yifang
Institution: University of California - Los Angeles , Michigan State University , University of California - Irvine , University of Southern California
Current Institution: University of California - Los Angeles , 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, 2001 through May 31, 2002
RFA: Airborne Particulate Matter (PM) Centers (1999) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Particulate Matter , Air


The overall objective of this research project is to focus on the central hypothesis of the Southern California Particle Center and Supersite, which is that organic constituents associated with particulate matter—including quinones, other organic compounds (polycyclic aromatic hydrocarbons [PAHs], nitro-PAHs, and aldehydes/ketones), and metals—are capable of generating reactive oxygen species and acting as electrophilic agents. They have a central role in allergic airway disease such as asthma and cardiovascular effects through their ability to generate oxidative stress, inflammation, and immunomodulating effects in the lungs and airways. The specific objective of this research project is to characterize ultrafine particles (UFPs) in the vicinity of major highways, particularly as they are transported downwind from the freeway.

Progress Summary:

We made identical measurements of UFPs, carbon monoxide (CO), and black carbon (BC) near two heavily traveled freeways, Interstate 405 (< 5 percent heavy-duty diesel trucks) and Interstate 710 (> 25 percent heavy-duty diesel trucks). As expected, the 405 Freeway had up to twice the CO concentration as the 710, and the 710 had two to four times the BC concentration as the 405. Both showed similar patterns for decay in UFP concentration with distance downwind from the freeway. At 30 m downwind, both showed strikingly similar trimodal UFP size distributions. Relative concentrations of UFPs, CO, and BC tracked each other well with distance from both freeways. We also made identical measurements of UFPs, CO, and BC in summer and winter for both freeways. We found that CO decreased more rapidly with distance from the freeway in summer than in winter, presumably because of greater vertical mixing in summer. We found the concentration of the smallest UFP (6-12 nm) to be more than two times greater in winter than in summer.

Figure 1. Relative Ultrafine Particle Number Concentration Versus Distance From the Edge of the Freeway. Wind direction is from left to right.

Future Activities:

We will attempt to develop a variation on our original UFP Concentration Model that would be easier to use and have a wider range of applicability. It would predict UFP concentration based on CO concentration and distance downwind from a freeway. We also plan to conduct preliminary studies of indoor/outdoor relationships of UFPs. We have established contacts in an office and in a residence immediately downwind of the 405 Freeway. Lastly, we plan to explore ways in which chemical composition of the two UFP modes can be analyzed separately. This may involve separation of the two modes and enough sampling for chemical analysis or individual particle analysis.

Journal Articles:

No journal articles submitted with this report: View all 13 publications for this subproject

Supplemental Keywords:

Particulate matter, quinones, PAHs, aldehydes, ketones, metals, allergic airway disease, human health risk, asthma, cardiovascular effects, oxidative stress, mobile sources, diesel exhaust particles, carbon monoxide, carbon black, ultrafine particle concentration model, California, freeway study,, RFA, Health, Scientific Discipline, PHYSICAL ASPECTS, Air, Geographic Area, particulate matter, Environmental Chemistry, Health Risk Assessment, State, Risk Assessments, mobile sources, Biochemistry, Physical Processes, engine exhaust, atmospheric particulate matter, urban air, motor vehicle emissions, atmospheric particles, automotive emissions, particulate emissions, airway disease, automobile exhaust, exposure, automobiles, automotive exhaust, diesel exhaust, air pollution, air sampling, human exposure, ultrafine particulate matter, diesel exhaust particles, frreway study, PM, PM characteristics, California (CA), airborne urban contaminants

Relevant Websites:

http://www.scpcs.ucla.edu/ exit EPA

Progress and Final Reports:

Original Abstract
  • 1999
  • 2000
  • 2001 Progress Report
  • 2003 Progress Report
  • 2004 Progress Report
  • Final Report

  • Main Center Abstract and Reports:

    R827352    Southern California Particle Center and Supersite

    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)