(Beijing) – The effects of bad air from the heavy clouds of pollution over many Chinese cities are becoming vividly clear, according to a recent study.

Air pollution was linked to at least 8,572 premature deaths across four major cities in 2012, in a study by Peking University and Greenpeace published December 18. The study also said smog in Chinese cities caused a total of 6.8 billion yuan in economic losses.