Explains how epidemiological tools can be used to guide the emergency management of chemical accidents and support actions to minimize adverse effects on health. Addressed to public health officials as well as epidemiologists, the book offers extensive practical advice on the choice of epidemiological methods: the design of studies, and the use of findings to support decisions during the acute phase, long-term follow-up, and the preparation of services to manage future incidents. Throughout, recommended uses of epidemiology draw on experiences gained during the investigation of several major chemical accidents in Europe. The book opens with an introduction to the nature of chemical accidents, routes of exposure, types of effects on health, and factors that can modify these effects. Against this background, guidelines are presented in three parts. The first explains the contributions of epidemiology to the immediate and longer-term management of a major chemical incident. Information includes the types of data needed according to the nature and phase of the emergency; sources of relevant data; and the ethical issues raised by studies. The second and most extensive part gives epidemiologists a comprehensive guide to the range of tools and approaches that may be needed when investigating an accident. Details range from advice on when rapid appraisals are appropriate, through a description of the advantages and disadvantages of using biomarkers of exposure, to a table listing diagnostic tests appropriate for measuring effects on specific organs and systems. The final part discusses the contribution of epidemiology as part of a multidisciplinary response to chemical emergencies. Further practical information is provided in an annex which summarizes methods used and lessons learned during the investigation of the chemical fire in Schweizerhalle, Switzerland; the escape of toxic chemicals in Seveso, Italy; the Shetland oil spill in the United Kingdom; and the toxic oil syndrome in Spain.. .