The study looked at how air pollution in China is affected by economic growth. They used data from 284 cities between 2004 and 2015 to see if there is a point where pollution decreases as income rises. The results show that there is a curve where pollution first increases, then decreases as income goes up. This curve is influenced by how cities are connected and how they use technology to reduce pollution. The findings suggest that as cities develop, they can reduce pollution by investing in cleaner technology.