Final Report: Modeling and Evaluation of Mechanisms Controlling the Outdoor/Indoor Relationships of Fine Particle Levels and Characteristics

EPA Grant Number: R826768
Title: Modeling and Evaluation of Mechanisms Controlling the Outdoor/Indoor Relationships of Fine Particle Levels and Characteristics
Investigators: Georgopoulos, Panos G. , Isukapalli, Sastry S. , Jayjock, Eric , Sun, Qing
Institution: Environmental and Occupational Health Sciences Institute
EPA Project Officer: Shapiro, Paul
Project Period: October 1, 1998 through September 30, 2000
Project Amount: $170,828
RFA: Air Pollution Chemistry and Physics (1998) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Air , Engineering and Environmental Chemistry


The objective of this research project was the development and application of new computational tools that provide state-of-the-art quantitative descriptions of the processes governing the dynamics of fine particulate matter (and associated gaseous photochemical pollutants) in the indoor environment, especially in relationship to the corresponding outdoor dynamics of these contaminants.

The methods and computational tools ("models" and "modules") developed through this work have been designed for use either as "stand-alone" models or as components of a new mechanistically consistent framework for source-to-dose exposure assessments, the Modeling Environment for Total Risk Studies (MENTOR). This system is not a "new model"; it is an evolving open "support environment" (i.e., a computational toolbox) intended to facilitate consistent multiscale exposure studies for individuals and populations.

Summary/Accomplishments (Outputs/Outcomes):

Two sets of indoor dynamics modules have been developed and applied in case studies. The first set provides a simplified option that expands/updates the treatment developed for the original Stochasic Human Exposure and Dose Simulation (SHEDS) model; it does not consider the details of physical and chemical processes taking place in the indoor environment. Rather, it uses a "lumped mass balance" to account for entrainment, removal, and source/formation processes. This option is computationally efficient and appropriate for large scale, population-based, exposure assessments. The second set of modules provides detailed descriptions of the chemical and physical processes governing aerosol and gas/aerosol processes, and is appropriate for focused studies of individual situations. In addition to modules that provide compatibility with existing regional and urban models of outdoor photochemical aerosol, other exploratory tools for processes that are unique to the indoor environment also are under continuing development; a case study of such an exploratory application is also presented in this study. The MENTOR implementation that incorporates these modules is MENTOR/SHEDS-Ozone and Particles Exposure and Risk Analysis Systems (OPERAS).

MENTOR/SHEDS-OPERAS provide a set of novel mechanistically based microenvironmental modeling tools that aim to improve the determination of outdoor/indoor relationships of photochemical pollutants and fine particles and, subsequently, of human exposure assessments. These modeling tools are used in conjunction with information from either ambient monitoring networks or from ambient urban and regional scale air quality models that incorporate detailed aerosol physics and chemistry coupled with gas phase photochemistry (specifically UAM-AERO,UAM-UDAERO, and MAQSIP-UDAERO) in their formation. The integration of ambient and microenvironmental information is accomplished using geographic information systems (GIS) tools to facilitate exposure scenario implementation.

Case studies showed the feasibility of modeling the indoor dynamics of gas/aerosol contaminants, using different levels of mechanistic detail that were consistent with descriptions employed in currently available outdoor models. The obtained results appear to agree qualitatively with many observed phenomena in the indoor microenvironment; however, it is expected that the information in databases from a variety of recently completed or currently ongoing studies will allow a quantitative evaluation and refinement of the indoor modeling analyses, in the near future.

Furthermore, the "families" of models that were developed through the present efforts can be used as "hypothesis generators" for the rational design of future laboratory and field studies. They can be used in ways that will optimize the content of information to be collected. Finally, models that were developed through this effort have been used successfully in comprehensive exposure studies (e.g., for urban Philadelphia, PA for the summer of 1999), demonstrating how detailed mechanistic approaches can refine past practices of human exposure and dose assessment for PM and ozone.

Journal Articles on this Report : 4 Displayed | Download in RIS Format

Other project views: All 9 publications 5 publications in selected types All 4 journal articles
Type Citation Project Document Sources
Journal Article Drossinos Y, Kevrekidis PG, Georgopoulos PG. Translational invariance in nucleation theories: theoretical formulation. Physical Review E 2001;63(3 Part 2):036123 (13 pp.). R826768 (Final)
  • Abstract from PubMed
  • Abstract: American Physical Society-Abstract
  • Journal Article Georgopoulos PG, Wang S-W, Vyas VM, Sun Q, Burke J, Vedantham R, McCurdy T, Ozkaynak H. A source-to-dose assessment of population exposures to fine PM and ozone in Philadelphia, PA, during a summer 1999 episode.Journal of Exposure Analysis and Environmental Epidemiology 2005;15(5):439-457. R826768 (Final)
  • Full-text: Nature-Full Text HTML
  • Abstract: Nature-Abstract
  • Other: Nature-Full Text PDF
  • Journal Article Georgopoulos PG, Lioy PJ. From a theoretical framework of human exposure and dose assessment to computational system implementation: the Modeling ENvironment for TOtal Risk Studies (MENTOR). Journal of Toxicology and Environmental Health, Part B-Critical Reviews 2006;9(6):457-483. R826768 (Final)
    R829391 (2006)
  • Abstract from PubMed
  • Abstract: Taylor and Francis-Abstract
  • Journal Article Kevrekidis PG, Lazaridis M, Drossinos Y, Georgopoulos PG. A unified kinetic approach to binary nucleation. Journal of Chemical Physics 1999;111(17):8010-8012. R826768 (Final)
  • Abstract: JCP-Abstract
  • Supplemental Keywords:

    indoor air aerosols, indoor air modeling, total human exposure, air, geographic area, health, RFA, scientific discipline, atmospheric sciences, East Coast, health risk assessment, physics, risk assessments, indoor air, particulate matter, Boston, Massachusetts, Region 1, aerosols, ambient aerosol, ambient air quality, ambient pollution control, ambient pollution control strategies, atmospheric chemistry, exposure, home, human exposure, indoor air chemistry, indoor air quality, modeling studies, multiple pathways, particle size., RFA, Scientific Discipline, Health, Air, Geographic Area, particulate matter, Health Risk Assessment, Physics, Risk Assessments, indoor air, Atmospheric Sciences, East Coast, particulates, ambient aerosol, ambient air quality, particle size, ambient pollution control strategies, home, Region1, exposure, indoor air chemistry, Boston, Massachusetts, human exposure, multiple pathways, indoor air quality, modeling studies, aerosols, atmospheric chemistry

    Relevant Websites: Exit

    Progress and Final Reports:

    Original Abstract
  • 1999