Air pollution is contamination of the indoor or outdoor environment by any chemical, physical or biological agent that modifies the natural characteristics of the atmosphere. Household combustion devices, motor vehicles, industrial facilities and forest fires are common sources of air pollution.
Today’s transport sector is predominantly based on the combustion of fossil fuels, making it one of the largest sources of both urban and regional air pollution. Recent studies estimate outdoor air pollution causes more than 3.2 million premature deaths each year worldwide.
