Has urbanization accelerated PM2.5 emissions? An empirical analysis with cross-country data

As a prominent indicator of economic development, urbanization can exert a significant impact on the PM2.5 level. Using panel data from 126 countries (areas) over the period 1990-2016, this study investigates the relationship between urbanization level and PM2.5 density. A modified stochastic impacts by regression on population, affluence, and technology model is applied as the empirical strategy. Results show that the relationship between urbanization and PM2.5 density has an inverted U shape. The effects of urban agglomeration and technological progress reduce the density of PM2.5 in the late stage of urbanization. This study can help policymakers design appropriate measures relevant to PM2.5 attenuation in the context of breakneck urbanization.