Particulate matter air pollution and national and county life expectancy loss in the USA: A spatiotemporal analysis
Population-weighted average PM2.5 concentration in 1,339 counties or merged county units (see Methods for description of analysis units).
(A) Concentrations in 2015. (B) Distribution of concentrations in 2015. (C) Reductions in concentrations from 1999 to 2015. (D) Relationship between concentration reductions from 1999 to 2015 and 1999 concentrations. PM2.5 concentrations in merged county units are population-weighted averages of constituent counties. PM2.5, fine particulate matter.