title: Risk of childhood asthma prevalence attributable to residential proximity to major roads in Montreal, Canada.
abstract: OBJECTIVE
  Exposure to traffic-related air pollutants plays a role in several health outcomes. A large body of evidence tends to link asthma in children with traffic exposure. Increasing asthma prevalence and incidence in children in Canadian cities has been of concern for public health authorities. The following study focuses on estimating the risk of asthma prevalence attributable to residing in proximity to major roads on the Island of Montreal, Canada.
  
  
  METHODS
  Risk functions pertaining to asthma in children and residential proximity to major roads were selected from the literature and applied to Montreal. Asthma prevalence was taken from population-based studies. Population data were retrieved from Canadian census. Exposure was estimated using the proximity to major road and highway category of the Desktop Mapping Technologies Inc. database (DMTI Spatial Inc.).
  
  
  RESULTS
  Based on different studies, the percentage of prevalent asthma cases attributable to residing within 50 metres of a major road or highway for children aged 2, 4 and 6 years varied between 2.4% (0-4.3), 5.6% (0.1-8.6) and 5.9% (0.1-9.0). For the 5-7 year age group residing within 75 m of a major road or highway, the percent of cases was 6.4% (2.6-9.3). For children aged 8 to 10 residing within 75 m of a highway only, the percent of cases was 0.7% (0.2-0.9).
  
  
  CONCLUSIONS
  These numbers represent the best crude estimates and are an indication of a possible range of cases linked to residential proximity to major roads. As there are uncertainties linked to the application of exposure-response functions, these estimates will be reassessed as new evidence is gathered through further research.
authors.affiliation: Direction de santé publique de I'Agence de la santé et des services sociaux de Montréal, Montreal, QC. kprice@santepub-mtl.qc.ca
authors.forename: Karine
authors.initials: K
authors.lastname: Price
authors.forename: Celine
authors.initials: C
authors.lastname: Plante
authors.forename: Sophie
authors.initials: S
authors.lastname: Goudreau
authors.forename: Elena Isabel Pascua
authors.initials: EI
authors.lastname: Boldo
authors.forename: Stéphane
authors.initials: S
authors.lastname: Perron
authors.forename: Audrey
authors.initials: A
authors.lastname: Smargiassi
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001249:Asthma / Q000453:epidemiology* / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D015995:Prevalence; D011634:Public Health; D011792:Quebec / Q000453:epidemiology; D012111:Residence Characteristics; D018570:Risk Assessment; D012307:Risk Factors; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D001335:Vehicle Emissions