Abstract

This document presents answers to 24 questions relevant to reviewing European policies on air pollution and to addressing health aspects of these policies. The answers were developed by a large group of scientists engaged in the WHO project “Review of evidence on health aspects of air pollution – REVIHAAP”. The experts reviewed and discussed the newly accumulated scientific evidence on the adverse effects on health of air pollution, formulating science-based answers to the 24 questions. Extensive rationales for the answers, including the list of key references, are provided. The review concludes that a considerable amount of new scientific information on the adverse effects on health of particulate matter, ozone and nitrogen dioxide, observed at levels commonly present in Europe, has been published in recent years. This new evidence supports the scientific conclusions of the WHO air quality guidelines, last updated in 2005, and indicates that the effects in some cases occur at air pollution concentrations lower than those serving to establish these guidelines. It also provides scientific arguments for taking decisive actions to improve air quality and reduce the burden of disease associated with air pollution in Europe.

This publication arises from the project REVIHAAP and has been co-funded by the European Union.

Contents

• Acknowledgements
• Abbreviations
• Introduction
  • 1. Scope of the project
  • 2. Process
  • 3. Sources of information and methodology
  • 4. Reconsideration and revision of guidelines
  • 5. From guidelines to limit values
  • 6. General issues of relevance to all pollutants
• A. Health effects of PM
  • Question A1
  • Question A2
  • Question A3
  • Question A4
  • Question A5
  • Question A6
• B. Health effects of ozone
  • Question B1
  • Question B2
  • Question B3
  • Question B4
• C. Proximity to roads, NO₂, other air pollutants and their mixtures
  • Question C1
  • Question C2
  • Question C3
  • Question C4
  • Question C5
  • Question C6
  • Question C7
  • Question C8
  • Questions A7 & C9
  • Question C10
• D. General questions
  • Question D1
  • Question D2
  • Question D4
• References
• List of invited experts participating in REVIHAAP

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The mention of specific companies or of certain manufacturers products does not imply that they are endorsed or recommended by the World Health Organization in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters.

All reasonable precautions have been taken by the World Health Organization to verify the information contained in this publication. However, the published material is being distributed without warranty of any kind, either express or implied. The responsibility for the interpretation and use of the material lies with the reader. In no event shall the World Health Organization be liable for damages arising from its use. The views expressed by authors, editors, or expert groups do not necessarily represent the decisions or the stated policy of the World Health Organization.

The views expressed herein can in no way be taken to reflect the official opinion of the European Union.

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The WHO European Centre for Environment and Health, Bonn, WHO Regional Office for Europe, coordinated the development of this publication