PM2.5 is a pollutant that is very hazardous to human health and potentially an important source of radiative forcing. We estimate the effect of economic growth on changes in PM2.5 pollution in a global panel of 151 countries between 1990 and 2010. We find that economic growth has positive though relatively small effects on pollution concentrations when we control for other relevant variables including the movement of pollution across international borders. Contrary to the environmental Kuznets curve (EKC) hypothesis, there is no in-sample income turning point after which growth reduces pollution concentrations. Though the EKC was originally developed to model the ambient concentrations of pollutants, most subsequent applications focused on pollution emissions. Despite this, previous research suggests that it is more likely that economic growth could eventually reduce the concentrations of local pollutants than emissions. Our results throw further doubt on the idea that economic growth can eventually reduce environmental impacts including climate change.