https://www.sciencedaily.com/releases/2021/06/210623141709.htm > "PM2.5 is the leading global environmental determinant of longevity. It is a key pollutant of concern for health," said Randall Martin, the Raymond R. Tucker Distinguished Professor in the Department of Energy, Environmental & Chemical Engineering in the McKelvey School of Engineering at Washington University in St. Louis. > New research from Martin's lab, in collaboration with the Goddard Space Flight Center, California Institute of Technology and Dalhousie University in Nova Scotia, mapped PM2.5 levels across China, Europe and North America. Using satellite data, ground-based monitoring and an innovative computer modeling system, researchers found mostly slight changes in PM2.5 -- with one exception.