Set against a background of growing public, media and political concern about occupational and environmental health issues, and a scientific need to better understand and explain the effects of pollutants on human health, this book is a unique resource. Contributions from an expert panel of international practitioners provide a comprehensive reference on the state of the art methods and applications in the field of occupational and environmental pollution and the adverse health effects, particularly the exposure assessment in epidemiological studies. Risks associated with occupational and environmental exposure are generally small, but the exposed population, and hence the population attributable risk, may be large. To detect small risk, the exposure assessment needs to be very refined. Exposure assessment is the study of the distribution and determinants of potentially hazardous agents, and includes the estimation of intensity, duration and frequency of exposure, the variation of these indices and their determinants. The aim of this book is to develop an understanding and knowledge of exposure assessment methods and their application to substantive issues in occupational and environmental epidemiology. The emphasis is on methodological principles and good practice. It is focused on exposure assessment in both occupational and environmental epidemiology since there are many similarities but also some interesting differences. The book outlines the basic principles of exposure assessment, and examines the current status and research questions in the exposure assessment of occupational and environmental epidemiological studies of allergens, particulate matter, chlorination disinfection by-products, agricultural pesticides and radiofrequencies. The book will be of interest to all concerned with exposure assessment and epidemiology. It will be a valuable source for undergraduate and postgraduate courses in exposure assessment, occupational hygiene, environmental science, epidemiology, toxicology, biostatistics, occupational and environmental health, health risk assessment and related disciplines and a useful resource of reference for policy makers and regulators.