The Relative Associations of Transition Metals and Sources of Fine Particulate Matter to Increased Daily Mortality

EPA Grant Number: R826245
Title: The Relative Associations of Transition Metals and Sources of Fine Particulate Matter to Increased Daily Mortality
Investigators:
Institution: Harvard T.H. Chan School of Public Health
Current Institution: Harvard University
EPA Project Officer: Hunt, Sherri
Project Period: January 14, 1998 through January 13, 2000
Project Amount: $211,733
RFA: Health Effects and Exposures to Particulate Matter and Associated Air Pollutants (1997) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Particulate Matter , Air , Health Effects

Description:

The EPA has identified specific gaps in current knowledge regarding the health effects of particulate matter (US EPA, 1996). Fine particulate matter (PM2.5) contains particles from mobile combustion sources, local stationary combustion sources, long-range transport from distant combustion sources, local industries, and non-combustion sources. The constituents of PM2.5 include sulfates, transition metals, crustal elements, and other elements associated with specific sources. While a convincing body of evidence has accumulated on the adverse effects of PM2.5, the specific chemical or physical characteristic responsible for these adverse effects has not been determined. The specific aim of this proposal is to examine the association of transition metals and sources of fine particles with mortality.

We propose to test two hypotheses regarding the effects of transition metals on mortality:

  1. (Total transition metals) The daily variation in total transition metals is a stronger determinant of daily mortality than the total mass of fine particles.
  2. (Combustion-related transition metals) The daily variation in transition metals in particles associated with combustion related sources is the strongest determinant of daily mortality. We propose to use the elemental composition of size-fractionated particles to identify sources of fine particles and to test two hypotheses:
  3. (Combustion-related fine particles) The combustion-related fine particles are more strongly associated with daily mortality than the non-combustion particles.
  4. (Specific sources of combustion-related fine particles) The combustion-related fine particles may be apportioned among specific sources (mobile combustion sources, local stationary combustion sources, long-range transport from distant combustion sources, and local industries) and fine particles from each source have different associations with daily mortality.

Approach:

Using state-of-the-art statistical methods, we propose to apportion the fine particulate matter in each city into specific sources, to compute the daily contribution of each source to ambient air pollution in each community, and to analyze the daily mortality in these communities compared to these estimates of source specific mass. This study will also use several newly developed techniques to evaluate the potential confounding by weather of the association of fine particles and mortality.

Expected Results:

This study will determine the relative contribution to human mortality of various forms of particulate air pollutants. The results of this study will greatly improve the scientific basis for future reassessment of the National Ambient Air Quality Standard for particulate matter. This study will couple a refined approach to modeling daily mortality with improved environmental data on the elemental composition of the fine particles.

Publications and Presentations:

Publications have been submitted on this project: View all 6 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 1 journal articles for this project

Supplemental Keywords:

ambient air, health effects, particulates, metals, sulfates, epidemiology., RFA, Health, Scientific Discipline, Air, particulate matter, air toxics, Environmental Chemistry, Risk Assessments, Environmental Monitoring, Atmospheric Sciences, ambient air quality, particle size, sulfates, weather, human health effects, PM 2.5, exposure and effects, statistical analysis, combustion emissions, air pollution, atmospheric transport, human exposure, National Ambient Air Quality Standards, particulate exposure, daily human mortality, particle transport

Progress and Final Reports:

Final Report