Final Report: Relationship Between Ultrafine Particle Size Distribution and Distance From Highways
EPA Grant Number: R827352C006Subproject: 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 , University of Southern California
EPA Project Officer: Stacey Katz/Gail Robarge,
Project Period: June 1, 1999 through May 31, 2005 (Extended to May 31, 2006)
RFA: Airborne Particulate Matter (PM) Centers (1999)
Research Category: Particulate Matter
Description:
Objective:Topic B: Studies of Emission Sources and Related Adverse Health Effects
It is now well established that increases in the concentration of fine particulate matter (PM2.5) in urban areas are associated with increases in morbidity and mortality. It is not known what components of PM2.5 cause these effects, but one candidate is the ultrafine particles (UF). These are particles less than 100 nm or 0.1 μm in size and are found near combustion sources, such as motor vehicles. In an urban environment motor vehicle emissions usually constitute the most important source of UF.
The overall objective of this research was to systematically evaluate and quantitatively predict UF particle concentration in the vicinity of freeways, particularly as they are transported downwind from freeways and into residences near freeways. Results from this study have provided data and tools that allow epidemiologists and toxicologists to estimate exposure to UF in the vicinity of major highways.
We made detailed measurements of UF near the 405 and 710 freeways, two of the busiest in the country. Interstate 405 carries more than 95% gasoline vehicles while Interstate 710 has up to 30% heavy-duty diesel vehicles. These freeways represent the range of vehicle mix one is likely to encounter in urban areas. Measurements were made in summer and in winter and during the day and at night to study the seasonal and diurnal variations of UF near freeways.
Particle number concentration and size distribution in the size range from 7 nm to 220 nm were measured by a condensation particle counter (CPC) and a scanning mobility particle spectrometer (SMPS), respectively. Measurements were taken at 30 m, 60 m, 90 m, 150 m, and 300 m downwind and 300 m upwind from Interstate highway 405 at the VA National Cemetery and at similar positions near Interstate 710. At each sampling point, the concentrations of carbon monoxide, black carbon and particle mass were also measured.
Summary/Accomplishments (Outputs/Outcomes):We found wind speed and direction, temperature, and relative humidity to be important factors in determining the local concentration of UF near freeways. The stronger the wind, the lower the total particle number concentration observed near freeways. The lower the temperature, or the higher the humidity, the higher the emission factor for UF especially for the primary mode particles below 30 nm. The maximum UF particle number concentration observed near freeways was about 25 times greater than background concentrations and decayed exponentially with downwind distance along the wind direction. Under the conditions of our measurements, CO, black carbon and particle number concentration track each other well with distance away from a freeway. Exponential decay was found to be a good estimator for the decrease in total particle number concentration with distance along the downwind direction. Strong seasonal and diurnal variations were found near freeways. Based on these experimental data, dispersion models and aerosol dynamic models were successfully developed that predict UF particle concentrations near freeways.
We also studied the penetration characteristics of freeway UF into nearby residences. Four two-bedroom apartments near the I-405 Freeway in Los Angeles, CA were selected for this study. Indoor (I) and outdoor (O) UF particle size distributions in the size range of 6 to 220 nm were measured simultaneously. We found significant amounts of freeway UF were able to penetrate into indoor environments. Particle number concentration I/O ratios showed strong dependence on particle sizes and were influenced by different ventilation mechanisms. Under natural ventilation, the highest I/O ratios (0.6–0.9) were usually observed for larger UF, while the lowest I/O ratios (0.1–0.4) occurred typically around 10–20 nm.
Technical Report:
Full Final Technical Report (PDF, 9pp., 118KB, about PDF)
Journal Articles on this Report: 13 Displayed | Download in RIS Format
Other subproject views: | All 13 publications | 13 publications in selected types | All 13 journal articles |
Other center views: | All 136 publications | 135 publications in selected types | All 135 journal articles |
Type | Citation | ||
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Kim HT, Zhu Y, Hinds WC, Lee KW. Experimental study of small cyclones as particle concentrators. Journal of Aerosol Science 2002;33(5):721-733. |
R827352 (Final) R827352C006 (Final) |
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Kim S, Shen S, Sioutas C, Zhu Y, Hinds WC. Size distribution and diurnal and seasonal trends of ultrafine particles in source and receptor sites of the Los Angeles Basin. Journal of the Air & Waste Management Association 2002;52(3):297-307. |
R827352 (2004) R827352 (Final) R827352C006 (Final) R827352C014 (Final) |
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Kuhn T, Krudysz M, Zhu Y, Fine PM, Hinds WC, Froines J, Sioutas C. Volatility of indoor and outdoor ultrafine particulate matter near a freeway. Journal of Aerosol Science 2005;36(3):291-302. |
R827352 (2004) R827352 (Final) R827352C006 (Final) R827352C014 (Final) |
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Li N, Hao M, Phalen RF, Hinds WC, Nel AE. Particulate air pollutants and asthma: a paradigm for the role of oxidative stress in PM-induced adverse health effects. Clinical Immunology 2003;109(3):250-265. |
R827352 (2004) R827352 (Final) R827352C002 (Final) R827352C006 (Final) R827352C016 (Final) |
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Zhang KM, Wexler AS, Zhu YF, Hinds WC, Sioutas C. Evolution of particle number distribution near roadways. Part II: The ‘Road-to-Ambient’ process. Atmospheric Environment 2004;38(38):6655-6665. |
R827352 (Final) R827352C006 (Final) R827352C014 (Final) |
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Zhang KM, Wexler AS, Niemeier DA, Zhu YF, Hinds WC, Sioutas C. Evolution of particle number distribution near roadways. Part III: Traffic analysis and on-road size resolved particulate emission factors. Atmospheric Environment 2005;39(22):4155-4166. |
R827352 (Final) R827352C006 (Final) R827352C014 (Final) |
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Zhu Y, Hinds WC, Kim S, Sioutas C. Concentration and size distribution of ultrafine particles near a major highway. Journal of the Air & Waste Management Association 2002;52(9):1032-1042. |
R827352 (Final) R827352C006 (Final) R827352C014 (Final) |
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Zhu Y, Hinds WC, Kim S, Shen S, Sioutas C. Study of ultrafine particles near a major highway with heavy-duty diesel traffic. Atmospheric Environment 2002;36(27):4323-4335. |
R827352 (Final) R827352C006 (Final) R827352C014 (Final) |
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Zhu Y, Hinds WC, Shen S, Sioutas C. Seasonal trends of concentration and size distribution of ultrafine particles near major highways in Los Angeles. Aerosol Science and Technology 2004;38(Suppl 1):5-13. |
R827352 (Final) R827352C006 (Final) R827352C014 (Final) |
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Zhu Y, Hinds WC, Krudysz M, Kuhn T, Froines J, Sioutas C. Penetration of freeway ultrafine particles into indoor environments. Journal of Aerosol Science 2005;36(3):303-322. |
R827352 (Final) R827352C006 (Final) R827352C014 (Final) |
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Zhu Y, Hinds WC. Predicting particle number concentrations near a highway based on vertical concentration profile. Atmospheric Environment 2005;39(8):1557-1566. |
R827352 (Final) R827352C006 (Final) |
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Zhu Y, Kuhn T, Mayo P, Hinds WC. Comparison of daytime and nighttime concentration profiles and size distributions of ultrafine particles near a major highway. Environmental Science & Technology 2006;40(8):2531-2536. |
R827352 (Final) R827352C006 (Final) |
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Zhu Y, Yu N, Kuhn T, Hinds WC. Field comparison of P-Trak and condensation particle counters. Aerosol Science and Technology 2006;40(6):422-430. |
R827352 (Final) R827352C006 (Final) |
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, Air, Geographic Area, Scientific Discipline, Health, RFA, PHYSICAL ASPECTS, Risk Assessments, Health Risk Assessment, Physical Processes, Biochemistry, particulate matter, Environmental Chemistry, mobile sources, State, automotive exhaust, California (CA), engine exhaust, airborne urban contaminants, urban air, ultrafine particulate matter, diesel exhaust, air sampling, particulate emissions, automobiles, human health risk, atmospheric particles, automobile exhaust, diesel exhaust particles, air pollution, airway disease, automotive emissions, atmospheric particulate matter, exposure, motor vehicle emissions, PM characteristics, human exposure, PM
Relevant Websites:
Full Final Technical Report (PDF, 9pp., 118KB, about PDF)
http://www.scpcs.ucla.edu
Progress and Final Reports:
2001 Progress Report
2002 Progress Report
2003 Progress Report
2004 Progress Report
Original Abstract
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)