Contributions to cities' ambient particulate matter (PM): A systematic review of local source contributions at global level (9 page pdf, Federico Karagulian, Claudio A. Belis, Carlos Francisco C. Dora, Annette M. Prüss-Ustün b, Sophie Bonjour b, Heather Adair-Rohani b, Markus Amann, Atmopsheric Environment, Nov. 2015)
Also discussed here: Urban air pollution: What are the main sources across the world? (Science Daily, Dec. 1, 2015)
Today we summarize the results of a paper that reviewed sources of PM2.5 and PM10 in 51 countries. By far the greatest source globally is traffic-related urban air pollution which amounted to 25% of ambient PM. The highest traffic emissions come from North America, Western Europe, Turkey and the Republic of Korea. The highest industrial pollution was found in Japan, Middle East and Southern Asia, Turkey, Brazil, Central Europe, and South Eastern Asia.
“from studies conducted in cities of 51 countries were used to calculate regional averages of sources of ambient particulate matter. Based on the available information, globally 25% of urban ambient air pollution from PM2.5 is contributed by traffic, 15% by industrial activities, 20% by domestic fuel burning, 22% from unspecified sources of human origin, and 18% from natural dust and salt.”
“as a result of gaseous traffic, heating and agriculture emissions appear to be most considerable in North America, Western Europe, Turkey and the Republic of Korea.”
"Traffic was the main contributor to urban ambient PM2.5 in several regions, including India (37%), South Eastern Asia (36%), Southwestern Europe (35%), Southern Asia (34%), Brazil (33%), and the Rest of the Americas (30%)”
“Industrial activities had the highest contributions from human activities in, Japan (34%), Middle East and Southern Asia (27%), Turkey (30%), Brazil (19%), Central Europe (17%), and South Eastern Asia (18%)”
“The Northern/Southern China, India, Southern Asia and Africa regions, showed the highest urban PM2.5 concentrations in average. On the other hand, the Middle Eastern, Northern China, Indian and African regions showed the highest absolute urban PM10 concentrations.”