title: Traffic-related air pollution and the onset of myocardial infarction: disclosing benzene as a trigger? A small-area case-crossover study.
abstract: OBJECTIVE
  Exposure to traffic is an established risk factor for the triggering of myocardial infarction (MI). Particulate matter, mainly emitted by diesel vehicles, appears to be the most important stressor. However, the possible influence of benzene from gasoline-fueled cars has not been explored so far.
  
  
  RESULTS
  We conducted a case-crossover study from 2,134 MI cases recorded by the local Coronary Heart Disease Registry (2000-2007) in the Strasbourg Metropolitan Area (France). Available individual data were age, gender, previous history of ischemic heart disease and address of residence at the time of the event. Nitrogen dioxide, particles of median aerodynamic diameter <10 µm (PM10), ozone, carbon monoxide and benzene air concentrations were modeled on an hourly basis at the census block level over the study period using the deterministic ADMS-Urban air dispersion model. Model input data were emissions inventories, background pollution measurements, and meteorological data. We have found a positive, statistically significant association between concentrations of benzene and the onset of MI: per cent increase in risk for a 1 µg/m3 increase in benzene concentration in the previous 0, 0-1 and 1 day was 10.4 (95% confidence interval 3-18.2), 10.7 (2.7-19.2) and 7.2 (0.3-14.5), respectively. The associations between the other pollutants and outcome were much lower and in accordance with the literature.
  
  
  CONCLUSIONS
  We have observed that benzene in ambient air is strongly associated with the triggering of MI. This novel finding needs confirmation. If so, this would mean that not only diesel vehicles, the main particulate matter emitters, but also gasoline-fueled cars--main benzene emitters-, should be taken into account for public health action.
authors.affiliation: Department of Epidemiology and Biostatistics, École des Hautes Études en Santé Publique, Rennes and Sorbonne Paris Cité, Paris, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Bard
authors.affiliation: Department of Epidemiology and Biostatistics, École des Hautes Études en Santé Publique, Rennes and Sorbonne Paris Cité, Paris, France.
authors.forename: Wahida
authors.initials: W
authors.lastname: Kihal
authors.affiliation: Association pour la Surveillance de la Qualité de l'Air en Alsace-ASPA, Schiltigheim, France.
authors.forename: Charles
authors.initials: C
authors.lastname: Schillinger
authors.affiliation: Department of Epidemiology and Biostatistics, École des Hautes Études en Santé Publique, Rennes and Sorbonne Paris Cité, Paris, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Fermanian
authors.affiliation: SEPIA-Santé, Baud, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Ségala
authors.affiliation: Department of Epidemiology and Biostatistics, École des Hautes Études en Santé Publique, Rennes and Sorbonne Paris Cité, Paris, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Glorion
authors.affiliation: Department of Epidemiology and Public Health (EA3430), University of Strasbourg, Strasbourg, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Arveiler
authors.affiliation: Laboratoire Image, Ville, Environnement (LIVE UMR7362 CNRS), Faculté de géographie et d'aménagement, University of Strasbourg, Strasbourg, France.
authors.forename: Christiane
authors.initials: C
authors.lastname: Weber
mesh_terms: D000328:Adult; D000368:Aged; D000397:Air Pollution / Q000009:adverse effects*; D001554:Benzene / Q000009:adverse effects*; D018592:Cross-Over Studies; D004784:Environmental Monitoring; D005260:Female; D005500:Follow-Up Studies; D005602:France; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology*; D052638:Particulate Matter / Q000009:adverse effects*; D011379:Prognosis; D012307:Risk Factors; D001335:Vehicle Emissions / Q000633:toxicity*
chemical_list: D052638:Particulate Matter; D001335:Vehicle Emissions; D001554:Benzene