Exposures and health outcomes from outdoor air pollutants in China.

China's economy has developed rapidly in the recent two decades. Economic development is usually linked with increase in energy consumption and consumption emissions, which in turn leads to worsening of air quality. Due to the adoption of various control measures, the ambient air quality in a number of large cities in China has actually improved. The ambient air TSP and SO(2) levels in China have been decreasing in the last decade. However, ambient air NO(x) level has been increasing due to the increased number of motor vehicles. Coal has been and is still the major source of energy in China. Ambient air pollution in large cities has changed from the conventional coal combustion type to the mixed coal combustion/motor vehicle emission type. A series of epidemiological studies on air pollution and health effects ranging from mortality, morbidity to functional changes have been conducted in China. The results showed that ambient air pollution had acute and chronic effects on mortality, morbidity, hospital admissions, clinical symptoms, lung function changes, etc. The exposure-response relationship between air pollutants and daily mortality, morbidity, hospital admissions, and lung function has been established accordingly.