Introduction: Air Pollution in China

This introduction provides an overview and analysis of key scientific data regarding air pollution in China. It constitutes a reference for understanding how policymakers, media and population in China make sense of and deal with air pollution, as discussed in the other articles of the section. We summarize the major characteristics and trends regarding air pollution in China, including its main sources and composition, levels of population exposure across the country, attributable mortality, and mitigation efforts. We also compare current levels of air pollution in China with other parts of the world and in a historical perspective. While the situation remains dire in many regions, particularly the Northeast, we conclude that there are signs of relief, or at least a halt to the increase in ambient air pollution levels. At the same time, critical issues regarding unequal levels of exposure remain, and health damaging levels of air pollution in cities will undoubtedly remain high for a long time to come. The rural population residing in areas close to industry and polluted cities and still depending on solid household fuels will likely be the worst off when it comes to air pollution exposure.