Article Text

Download PDFPDF
Air pollution and emergency admissions in Boston, MA
  1. Antonella Zanobetti,
  2. Joel Schwartz
  1. Department of Environmental Health, Harvard School of Public Health, Boston, USA
  1. Correspondence to:
 Dr A Zanobetti
 Department of Environmental Health, Exposure Epidemiology and Risk Program, Harvard School of Public Health, 401 Park Drive, Landmark Center, Suite 415, PO Box 15698, Boston, MA 02215, USA; azanobet{at}


Study Objective: Many studies have shown that ambient particulate air pollution (PM) is associated with increased risk of hospital admissions and deaths for cardiovascular or respiratory causes around the world. In general these have been analysed in association with PM10 and ozone, whereas PM2.5 is now the particle measure of greatest health and regulatory concern. And little has been published on associations of hospital admissions and PM components.

Design: This study analysed hospital admissions for myocardial infarction (15 578 patients), and pneumonia (24 857 patients) in associations with fine particulate air pollution, black carbon (BC), ozone, nitrogen dioxide (NO2), PM not from traffic, and carbon monoxide (CO) in the greater Boston area for the years 1995–1999 using a case-crossover analysis, with control days matched on temperature.

Main results: A significant association was found between NO2 (12.7% change (95% CI: 5.8, 18)), PM2.5 (8.6% increase (95% CI: 1.2, 15.4)), and BC (8.3% increase (95% CI: 0.2, 15.8)) and the risk of emergency myocardial infarction hospitalisation; and between BC (11.7% increase (95% CI: 4.8, 17.4)), PM2.5 (6.5% increase (95% CI: 1.1, 11.4)), and CO (5.5% increase (95% CI: 1.1, 9.5)) and the risk of pneumonia hospitalisation.

Conclusions: The pattern of associations seen for myocardial infarction and pneumonia (strongest associations with NO2, CO, and BC) suggests that traffic exposure is primarily responsible for the association with heart attacks.

  • NO2, nitrogen dioxide
  • BC, black carbon, PM, particulate matter
  • CO, carbon monoxide
  • MI, myocardial infarction
  • air pollution
  • myocardial infarction
  • case-crossover
  • fine particulate air pollution
  • pneumonia

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • Funding: this study was funded by the EPA/Harvard Center on Ambient Particle Health Effects EPA PM Center: US EPA Grant R827353.

  • Competing interests: none.

Linked Articles

  • In this issue
    Carlos Alvarez-Dardet John R Ashton