Grantee Research Project Results
2003 Progress Report: Controlled Human Exposure Studies with Concentrated PM
EPA Grant Number: R827352C012Subproject: this is subproject number 012 , 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 Children's Environmental Health Center
Center Director: McConnell, Rob Scot
Title: Controlled Human Exposure Studies with Concentrated PM
Investigators: Gong, Henry , Linn, William S. , Sioutas, Constantinos
Current Investigators: Gong, Henry
Institution: University of Southern California , Rancho Los Amigos Medical Center
Current Institution: Rancho Los Amigos Medical Center
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 objective of this research project is to investigate the hypotheses that: (1) ambient particles are responsible for short-term cardiopulmonary health effects observed in Los Angeles and other urban areas on “high-pollution” days; (2) specific effects depend on particle size, composition, dosing characteristics, and preexisting health risk factors; and (3) these effects can be demonstrated clearly by controlled exposures of volunteers representing “high-risk” segments of the exposed population.
This is one of the research projects funded by the Southern California Particle Center and Supersite (SCPCS). The progress for the other projects is reported separately (see reports for R827352, R827352C001 through R827352C017, and R827352C019 through R827352C021.
Progress Summary:
We employ ambient particle concentrators interfaced to exposure chambers to investigate these effects in human volunteers. We have documented effects of fine particulate matter (PM2.5) and coarse particles (PM10-2.5) and currently are investigating ultrafine (UF) particles (PM0.1) in the primary pollution (coastal) region of Los Angeles. Volunteer subjects have included younger adults, both healthy and with asthma, and older adults, both healthy and with chronic obstructive pulmonary disease (COPD).
To date, nine subjects (four healthy, five asthmatic) have completed exposure studies with concentrated UF particles as well as sham-control studies with filtered air. Initial exposures exhibited inconsistent (frequently low) particle counts relative to mass concentration. This eventually was found to be attributable to a combination of intermittently low output of UF particles from some concentrator modules and leakage of ambient air (containing larger particles) into the exposure chamber. To alleviate these problems, exposures via facemask have been adopted in place of whole-body exposures. The revised system appears to be functioning well, achieving generally higher and more consistent particle concentrations in the subject’s breathing zone (typically 125,000 per mL or more by condensation particle counter measurement; 200 μg/m3 or more by gravimetric analysis). No overall net loss of lung function (forced expired volume in 1 second) was found after UF particle exposure. Asthmatics on average, however, showed a slight decline in lung function (mean 15 mL), significantly different (P < 0.05) from healthy subjects, who showed a slight gain (mean 61 mL). Currently, it is unclear whether this effect relates to asthmatic status or to generally higher exposure levels in asthmatics.
Future Activities:
We will continue testing the hypothesis that short-term cardiorespiratory effects of ambient UF particles can be demonstrated by proper experimental combinations of ambient pollution and susceptible subjects. This will be done through additional exposures of asthmatic volunteers at the current laboratory site in Downey (typical of the central Los Angeles region with heavy primary particle pollution) using the current experimental protocol incorporating a wide range of heart, lung, and blood measurements. Given that only modest health effects have been found in preliminary analyses of UF exposure data, the accumulation of a larger sample size for the existing subject groups is indicated (rather than a shift to elderly/COPD subjects). A larger sample will improve statistical power to detect subtle effects. At the conclusion of Year 6 exposure studies, our pooled exposure and response data set will include 60 or more individuals with 2-6 studies each, 3 different risk factors (advanced age, asthma, COPD), and 3 different particle size ranges (UF, fine, coarse). Analysis of this pooled data set can potentially identify relationships between health endpoints and exposure factors that are not obvious within data from individual experiments. This will be pursued in collaboration with the Southern California Particle Center and Supersite (SCPCS) statistician (Daniel Stram, Ph.D.).
Journal Articles:
No journal articles submitted with this report: View all 9 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, Health, Scientific Discipline, Air, Geographic Area, particulate matter, Environmental Chemistry, Health Risk Assessment, State, Risk Assessments, ambient aerosol, asthma, particulates, epidemiology, human health effects, toxicology, airway disease, allergic airway disease, exposure, air pollution, children, PAH, human exposure, particulate exposure, trajectory modeling, California (CA), allergens, indoor air quality, aerosols, atmospheric chemistry, dosimetry, particle transport, particle concentrator, airborne urban contaminants, cardiovascular diseaseRelevant Websites:
Progress and Final Reports:
Original AbstractMain Center Abstract and Reports:
R827352 Southern California Children's Environmental 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
9 journal articles for this subproject
Main Center: R827352
150 publications for this center
149 journal articles for this center