1999 Progress Report: Examining Conditions That Predispose Towards Acute Adverse Effects of Particulate Exposures

EPA Grant Number: R827353C004
Subproject: this is subproject number 004 , established and managed by the Center Director under grant R827353
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: Harvard Particle Center
Center Director: Koutrakis, Petros
Title: Examining Conditions That Predispose Towards Acute Adverse Effects of Particulate Exposures
Investigators: Schwartz, Joel
Current Investigators: Schwartz, Joel , O'Neill, M. , Wellenius, Gregory , Zanobetti, Antonella
Institution: Harvard T.H. Chan School of Public Health , Harvard University
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, 1999 through May 31, 2000
Project Amount: Refer to main center abstract for funding details.
RFA: Airborne Particulate Matter (PM) Centers (1999) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Particulate Matter , Air


This project is one of four projects under Theme II: Identifying Populations Susceptible to the Health Effects of Particulate Air Pollution of our proposal. This project will test the hypothesis that patients with pre-existing respiratory, cardiovascular, or diabetic conditions have an enhanced mortality response to particle exposures. In addition, it will separately assess the effects of gaseous co-pollutants as alternative predictors of mortality and the degree to which they modify response to particulate matter (PM). This project was intended to address Particulate Matter Research Topics 7 and 8 identified by the National Research Council (NRC)-Combined Effects of Particulate Matter and Gaseous Co-Pollutants and Susceptible Subpopulations.

Progress Summary:

Combined Effects of PM and Gaseous Co-Pollutants. Previous city-specific analyses have assessed confounding of the PM associations by gaseous pollutants using traditional regression methods. We have applied newly developed multi-city analytic approaches to use the additional information in multiple cities with varying compositions of the air pollution mixture to address this issue.

We examined the association of daily deaths and ambient particles in 10 U.S. cities with daily measurements of PM10, SO2, O3, and CO (Schwartz, 2000). To assess confounding of the particle and daily mortality associations, city- and season-specific PM10 effect estimates were regressed against the regression coefficients of PM10 against each of the gaseous pollutants. Controlling for the gaseous pollutants by this method did not substantially or significantly change the estimated daily mortality effects of PM10 in these cities.

Susceptible Subpopulations. Using combined analyses of daily hospital admissions and mortality data, we have examined differences in response to PM exposure by sex, race, and socioeconomic status. We are identifying pre-existing medical conditions that increase risk for response to PM exposures. We are assessing how much of the observed increase in daily mortality is due to small advances in the date of death among seriously ill subjects (harvesting).

In the four largest U.S. cities with daily PM10 measurements (Chicago, Detroit, Minneapolis-St. Paul, and Pittsburgh), Zanobetti and Schwartz (2000) estimated that the effect of PM10 on daily mortality was one-third larger in women compared to men. However, they found little evidence for effect modification by race or by socioeconomic indicators.

In the previously cited analysis of 10 U.S. cities, Schwartz (2000) found that socioeconomic differences between the cities did not explain the observed differences in the city-specific PM10 associations with daily mortality. As in previous studies, the increase in deaths out of hospital 0.89 percent (95 percent CI 0.67 percent to 1.10 percent) per 10 g/m3 PM10 was substantially greater than the increase in deaths in hospital (0.49 percent, 95 percent CI 0.31 percent to 0.68 percent).

Zanobetti and Schwartz (2000) tested whether previous admissions or secondary diagnoses for respiratory illness increased the risk of cardiovascular hospital admission associated with ambient PM10 exposure. Based on Detroit hospitalizations of the elderly, they found that a concurrent or previous hospitalization for a respiratory infection more than doubled the risk of a particulate air pollution associated admission for cardiovascular disease. A previous admission for chronic obstructive pulmonary disease also was associated with increased risk of a PM10-associated cardiovascular admission.

Braga, et al. (2000) assessed confounding of the air pollution-daily mortality associations by respiratory epidemics in five U.S. cities. Respiratory epidemic periods were identified by excess pneumonia hospital admissions in each city. Controlling for the respiratory epidemics only slightly reduced the estimated effect of PM10 on daily mortality. The combined effect estimate across the five cities adjusted for respiratory epidemics was 0.85 percent (95 percent CI 0.60 percent to 1.10 percent) for each 10 g/m3 PM10, showing that the observed associations were not confounded by respiratory epidemics.

Schwartz (2000) examined harvesting in a time series analysis of PM10 and daily mortality and hospital admissions in Chicago, to assess the net effect of PM10 exposures without any harvesting effects. Associations were estimated with successively larger time windows between 15 and 60 days. If only the most susceptible were having their date of death advanced by a few days, then by considering longer averaging times, any short-term deaths or admissions due to harvesting would not be counted. If harvesting were important, then the estimated associations should decrease in magnitude as the time windows increased. In contrast, the estimated effect of PM10 on daily mortality increases with window size. There was no change in deaths of patients in the hospital, while the estimated effect of PM10 on deaths of subjects out of the hospital increased more than three-fold. This suggests that particle exposures are increasing the risk of sudden death in subjects with apparently good health but underlying heart disease.

Future Activities:

We will continue to apply the second stage analytic methods to hospital admissions data and to other cities to assess the effects of co-pollutants. For susceptible subpopulations, we will assess response to particulate exposure among well-characterized patients in existing follow-up studies. Data collection currently is underway to assess particulate response among adult participants in the Six Cities study through continued follow-up. In addition, data are being collected to assess markers of inflammatory response following PM exposure among participants in the normative aging study.

Journal Articles:

No journal articles submitted with this report: View all 34 publications for this subproject

Supplemental Keywords:

particulate matter, PM2.5, PM10, air pollutants, particulates, health effects, exposure, ambient particles, susceptibility, metals, public policy, biology, engineering, epidemiology, toxicology, environmental chemistry, monitoring., RFA, Health, Scientific Discipline, Air, Geographic Area, particulate matter, Toxicology, air toxics, Environmental Chemistry, Epidemiology, State, Risk Assessments, Microbiology, Susceptibility/Sensitive Population/Genetic Susceptibility, Environmental Microbiology, Environmental Monitoring, Children's Health, genetic susceptability, tropospheric ozone, Atmospheric Sciences, Molecular Biology/Genetics, Biology, Environmental Engineering, ambient air quality, health effects, monitoring, risk assessment, sensitive populations, chemical exposure, interindividual variability, molecular epidemiology, particulates, air pollutants, exposure and effects, lung, stratospheric ozone, ambient air monitoring, health risks, cardiopulmonary responses, indoor exposure, human health effects, ambient air, pulmonary disease, developmental effects, epidemelogy, respiratory disease, exposure, biological response, ambient measurement methods, Utah (UT), ambient monitoring, children, lung cancer, air pollution, Massachusetts (MA), particle exposure, biological mechanism , Human Health Risk Assessment, human exposure, inhalation, pulmonary, ambient particle health effects, cardiopulmonary response, particulate exposure, susceptibility, assessment of exposure, Illinois (IL), elderly, inhaled, atmospheric monitoring, human susceptibility, inhalation toxicology, indoor air, epidemeology, environmental health hazard, Connecticut (CT), cardiopulmonary, human health, indoor air quality, inhaled particles, respiratory, dosimetry, genetic susceptibility, air quality, cardiovascular disease

Relevant Websites:

http://www.hsph.harvard.edu/epacenter/homeframe.htm Exit

Progress and Final Reports:

Original Abstract
  • 2000 Progress Report
  • 2001 Progress Report
  • 2002 Progress Report
  • 2003 Progress Report
  • 2004 Progress Report
  • Final Report

  • Main Center Abstract and Reports:

    R827353    Harvard Particle Center

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R827353C001 Assessing Human Exposures to Particulate and Gaseous Air Pollutants
    R827353C002 Quantifying Exposure Error and its Effect on Epidemiological Studies
    R827353C003 St. Louis Bus, Steubenville and Atlanta Studies
    R827353C004 Examining Conditions That Predispose Towards Acute Adverse Effects of Particulate Exposures
    R827353C005 Assessing Life-Shortening Associated with Exposure to Particulate Matter
    R827353C006 Investigating Chronic Effects of Exposure to Particulate Matter
    R827353C007 Determining the Effects of Particle Characteristics on Respiratory Health of Children
    R827353C008 Differentiating the Roles of Particle Size, Particle Composition, and Gaseous Co-Pollutants on Cardiac Ischemia
    R827353C009 Assessing Deposition of Ambient Particles in the Lung
    R827353C010 Relating Changes in Blood Viscosity, Other Clotting Parameters, Heart Rate, and Heart Rate Variability to Particulate and Criteria Gas Exposures
    R827353C011 Studies of Oxidant Mechanisms
    R827353C012 Modeling Relationships Between Mobile Source Particle Emissions and Population Exposures
    R827353C013 Toxicological Evaluation of Realistic Emissions of Source Aerosols (TERESA) Study
    R827353C014 Identifying the Physical and Chemical Properties of Particulate Matter Responsible for the Observed Adverse Health Effects
    R827353C015 Research Coordination Core
    R827353C016 Analytical and Facilities Core
    R827353C017 Technology Development and Transfer Core