J Epidemiol Community Health 63:960-966 doi:10.1136/jech.2008.084012
  • Research report

The temporal pattern of mortality responses to ambient ozone in the APHEA project

  1. E Samoli1,
  2. A Zanobetti2,
  3. J Schwartz2,
  4. R Atkinson3,
  5. A LeTertre4,
  6. C Schindler5,
  7. L Pérez6,
  8. E Cadum7,
  9. J Pekkanen8,9,
  10. A Paldy10,
  11. G Touloumi1,
  12. K Katsouyanni1
  1. 1
    Departement of Hygiene, Epidemiology & Medical Statistics, University of Athens, Greece
  2. 2
    Harvard School of Public Health, Boston, USA
  3. 3
    St George’s, University of London, UK
  4. 4
    Environmental Health Unit, National Institute of Public Health Surveillance, Paris, France
  5. 5
    Institute of Social and Preventive Medicine, University of Basel, Switzerland
  6. 6
    CREAL-Barcelona, Spain
  7. 7
    Center for Epidemiology and Environmental Health, Regional Agency for Environmental Protection, Turin, Italy
  8. 8
    Department of Environmental Health, National Public Health Institute (KTL), Finland
  9. 9
    School of Public Health and Clinical Nutrition, University of Kuopio, Finland
  10. 10
    National Institute of Environmental Health, Budapest, Hungary
  1. Correspondence to Dr E Samoli, Department of Hygiene and Epidemiology, University of Athens Medical School, 75 Mikras Asias Street, 115 27 Athens, Greece; esamoli{at}
  • Accepted 27 April 2009
  • Published Online First 30 July 2009


Background: The temporal pattern of effects of summertime ozone (O3) in total, cardiovascular and respiratory mortality were investigated in 21 European cities participating in the APHEA-2 (Air Pollution and Health: a European Approach) project, which is fundamental in determining the importance of the effect in terms of life loss.

Methods: Data from each city were analysed separately using distributed lag models with up to 21 lags. City-specific air pollution estimates were regressed on city-specific covariates to obtain overall estimates and to explore sources of possible heterogeneity.

Results: Stronger effects on respiratory mortality that extend to a period of 2 weeks were found. A 10 μg/m3 increase in O3 was associated with a 0.36% (95% CI −0.21% to 0.94%) increase in respiratory deaths for lag 0 and with 3.35% (95% CI 1.90% to 4.83%) for lags 0–20. Significant adverse health effects were found of summer O3 (June–August) on total and cardiovascular mortality that persist up to a week, but are counterbalanced by negative effects thereafter.

Conclusions: The results indicate that studies on acute health effects of O3 using single-day exposures may have overestimated the effects on total and cardiovascular mortality, but underestimated the effects on respiratory mortality.


  • ▸ Supplemental file published online only at

  • Funding This work was funded through two grants from the European Commission (EC) Environment and Climate Programme (contract numbers ENV4-CT97-0534 and QLK4-CT-2001-30055).

  • Competing interests None.

  • Provenance and Peer review Not commissioned; externally peer reviewed.