Time-space modeling of journey-time exposure to traffic-related air pollution using GIS

Environ Res. 2005 Jan;97(1):10-25. doi: 10.1016/j.envres.2004.05.002.


Journey-time exposures represent an important, though as yet little-studied, component of human exposure to traffic-related air pollution, potentially with important health effects. Methods for assessing journey-time exposures, either as part of epidemiological studies or for policy assessment, are, however, poorly developed. This paper describes the development and testing of a GIS-based system for modeling human journey-time exposures to traffic-related air pollution: STEMS (Space-Time Exposure Modeling System). The model integrates data on source activity, pollutant dispersion, and travel behavior to derive individual- or group-level exposure measures to atmospheric pollution. The model, which is designed to simulate exposures of people as they move through a changing air pollution field, was developed, validated, and trialed in Northampton, UK. The system currently uses ArcInfo to couple four separate submodels: a source activity/emission model (SATURN), a proprietary atmospheric dispersion model (ADMS-Urban), an empirically derived background air pollution model, and a purposely designed time-activity-based exposure model (TOTEM). This paper describes the structure of the modeling system; presents results of field calibration, validation, and sensitivity analysis; and illustrates the use of the model to analyze journey-time exposures of schoolchildren.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Air Pollution / analysis*
  • Child
  • England
  • Environmental Exposure*
  • Geographic Information Systems*
  • Humans
  • Models, Theoretical*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Software*
  • Time Factors
  • Transportation*