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Short term effects of ambient sulphur dioxide and particulate matter on mortality in 12 European cities: results from time series data from the APHEA project

BMJ 1997; 314 doi: (Published 07 June 1997) Cite this as: BMJ 1997;314:1658
  1. K Katsouyanni, associate professora,
  2. G Touloumi, research fellowa,
  3. C Spix, statisticianb,
  4. J Schwartz, associate professorc,
  5. F Balducci, research fellowd,
  6. S Medina, senior researchere,
  7. G Rossi, researcherf,
  8. B Wojtyniak, senior researcherg,
  9. J Sunyer, scientisth,
  10. L Bacharova, internisti,
  11. J P Schouten, associate professorj,
  12. A Ponka, headk,
  13. H R Anderson, professorl
  1. a Department of Hygiene and Epidemiology, University of Athens Medical School, Athens 115 27, Greece
  2. b GSF- Forschungszentrum für Umwelt und Gesundheit, Institut für Epidemiologie Postfach 1129 Neuherberg, Germany
  3. c Harvard School of Public Health, Environmental Epidemiology Program, Boston, MA 02115, USA
  4. d Faculté de Medicine, Université de Grenoble, Department of Public Health, Domaine de la Merci, F-38706, La Tronche, Cedex, France
  5. e Observatoire Regional de la Santé, Paris, ORS Ile de France, 75732 Paris Cedex 15, France
  6. f Institute of Clinical Physiology, National Research Council, IFC-CNR, 56100 Pisa, Italy
  7. g National Institute of Hygiene, 00-791 Warsaw, Poland
  8. h Institut Municipal D' Investigacio Medica, E-08003, Barcelona, Spain
  9. i National Centre for Health Promotion, 82007 Bratislava, Slovakia
  10. j Department of Epidemiology and Statistics, University of Groningen, Groningen 9713, Netherlands
  11. k Helsinki City Centre of the Environment, Environmental Health Unit, 00530 Helsinki, Finland
  12. l Department of Public Health Sciences, St George's Hospital Medical School, London SW17 0RE
  1. Correspondence to: Dr Katsouyanni
  • Accepted 13 March 1997


Objectives: To carry out a prospective combined quantitative analysis of the associations between all cause mortality and ambient particulate matter and sulphur dioxide.

Design: Analysis of time series data on daily number of deaths from all causes and concentrations of sulphur dioxide and particulate matter (measured as black smoke or particles smaller than 10 μm in diameter (PM10)) and potential confounders.

Setting: 12 European cities in the APHEA project (Air Pollution and Health: a European Approach).

Main outcome measure: Relative risk of death.

Results: In western European cities it was found that an increase of 50 μg/m3 in sulphur dioxide or black smoke was associated with a 3% (95% confidence interval 2% to 4%) increase in daily mortality and the corresponding figure for PM10 was 2% (1% to 3%). In central eastern European cities the increase in mortality associated with a 50 μg/m3 change in sulphur dioxide was 0.8% (-0.1% to 2.4%) and in black smoke 0.6% (0.1% to 1.1%). Cumulative effects of prolonged (two to four days) exposure to air pollutants resulted in estimates comparable with the one day effects. The effects of both pollutants were stronger during the summer and were mutually independent.

Conclusions: The internal consistency of the results in western European cities with wide differences in climate and environmental conditions suggest that these associations may be causal. The long term health impact of these effects is uncertain, but today's relatively low levels of sulphur dioxide and particles still have detectable short term effects on health and further reductions in air pollution are advisable.

Key messages

  • Evidence is accumulating that air pollution below the levels of national and international standards has adverse short term health effects

  • In this study data from 12 European cities showed that increases in sulphur dioxide and particulate matter are associated with increased total mortality

  • The effects of the two pollutants seem to be independent

  • Associations were stronger and more consistent in western European cities

  • Current low levelsof sulphur dioxide and particles stillaffect health and further reductions in pollution are needed


    • Accepted 13 March 1997
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