Urban air quality is a topic which remains high on the scientific and political agenda. Concentrations of most air pollutants are higher in urban areas than in the surrounding rural regions, and given the high population densities, it is within urban areas that the majority of the population receive their air pollutant exposure. Despite the continued implementation of abatement measures, concentrations of air pollutants within urban areas frequently exceed health-based guidelines and stricter measures to restrict emissions are required. This comprehensive volume, written by authoritative authors, deals with the basic science of urban air pollution in relation to the sources and concentrations, and the atmospheric chemical and physical processes which determine those concentrations and lead to the formation of secondary pollutants by chemical reactions in the atmosphere. The health effects of urban air pollution are described as is the policy response designed to mitigate the problems. Some of the highest air pollutant exposures occur within underground railway systems and this topic is considered explicitly in its own chapter. With comprehensive coverage from sources through atmospheric processes, to human exposure and effects on health and the policy response, this topical work will be of interest to scientists and policy makers within this field as well advanced students.

This volume of the Encyclopedia of Sustainability Science and Technology, Second Edition, provides a broad and comprehensive view of air pollution, extending from ground-level, localized air quality and regional and global air quality and effects, to sensors and measurement and air pollution control. Despite substantial improvements in many parts of the world, globally, air pollution remains the most hazardous environmental threat. The increasing quality of exposure assessments, access to new and better statistical methods, and more complete and precise health data have led to stronger associations between air pollution exposure and health effects. Air pollution exposure-effect relationships have now been established for a wide variety of health outcomes, and well documented through parallel studies in many countries around the world using a variety of approaches and methodologies. Assessments of the health effects in the population are now performed on a routine basis in many countries and by many agencies, and often these also include calculation of externalities associated with the negative health effects. Such knowledge is essential for pushing development towards a more sustainable society. This volume covers topics including, but not limited to, basic knowledge to understand foundational concepts and drivers of regional and global air pollution in relation to air quality and ways to sense, measure and control pollutants, while placing this knowledge into the perspectives of health and technological systems.