title: Assessment of Exposure of Elementary Schools to Traffic Pollution by GIS Methods.
abstract: OBJECTIVE
  The susceptibility of children to polluted air has been pointed out several times in the past. Generally, children suffer from higher exposure to air pollutants than adults because of their higher physical activity, higher metabolic rate and the resultant increase in minute ventilation. The aim of this study was to examine the exposure characteristics of public elementary schools in Prague (the capital of the Czech Republic).
  
  
  METHODS
  The exposure was examined by two different methods: by the proximity of selected schools to major urban roads and their location within the modeled urban PM10 concentration fields. We determined average daily traffic counts for all roads within 300 m of 251 elementary schools using the national road network database and geographic information system and calculated by means of GIS tools the proximity of the schools to the roads. In the second method we overlapped the GIS layer of predicted annual urban PM10 concentration field with that of geocoded school addresses.
  
  
  RESULTS
  The results showed that 208 Prague schools (almost 80%) are situated in a close proximity (<300 m) of roads exhibiting high traffic loads. Both methods showed good agreement in the proportion of highly exposed schools at risk; however, we found significant differences in the locations of schools at risk determined by the two methods.
  
  
  CONCLUSIONS
  We argue that results of similar proximity studies should be treated with caution before they are used in risk based decision-making process, since different methods may provide different outcomes.
authors.affiliation: Department of Applied Geoinformatics and Cartography, Faculty of Science, Charles University in Prague, Prague, Czech Republic.
authors.forename: Přemysl
authors.initials: P
authors.lastname: Štych
authors.affiliation: Institute for Environmental Studies, Faculty of Science, Charles University in Prague, Prague, Czech Republic.
authors.forename: Denisa
authors.initials: D
authors.lastname: Šrámková
authors.affiliation: Institute for Environmental Studies, Faculty of Science, Charles University in Prague, Prague, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Braniš
mesh_terms: D000293:Adolescent; D002648:Child; D018153:Czech Republic; D004781:Environmental Exposure / Q000032:analysis*; D005260:Female; D040362:Geographic Information Systems; D006801:Humans; D008297:Male; D018570:Risk Assessment; D012574:Schools; D014505:Urban Population; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D001335:Vehicle Emissions
keywords: GIS; health effects; particulate matter; schools; traffic density; traffic pollution