Air pollution and cancer-risk assessment methodology and epidemiological evidence: A preface

In the fall of 1977, a Swedish Governmental Committee on Energy and Environment submitted to the Swedish government an extensive evaluation concerning environmental and health effects of different sources of energy including nuclear energy and fossil fuels. The National Swedish Environment Protection Board was charged with responsibility for a critical review of potential environmental and health effects relating to the use of fossil fuels as energy sources while the National Swedish Institute for Radiation Protection was charged with a similar review concerning effects from the use of nuclear power. During the review several key questions arose which were felt to be of importance not only for Sweden, but also more generally. The Governmental Committee on Energy and Environment therefore asked the Karolinska Institute to arrange an international meeting for the discussion of such questions. The meeting was organized by the Karolinska Institute through its Department of Environmental Hygiene, which is also a World Health Organization Collaborating Center for Environmental Health Effects and was held in Stockholm March 8-11. A main objective of the meeting was to consider current scientific knowledge about carcinogenic substances in air in relation to epi-