You are here:
Significantly Reduced Health Burden from Ambient Air Pollution in the United States under Emission Reductions from 1990 to 2016
Zhang, Y., J. West, R. Mathur, J. Xing, C. Hogrefe, S. Roselle, J. Bash, Jon Pleim, M. Gan, David-C Wong, D. Tong, A. Donkelaar, AND R. Martin. Significantly Reduced Health Burden from Ambient Air Pollution in the United States under Emission Reductions from 1990 to 2016. 2017 AGU Fall Meeting, New Orleans, LA, December 11 - 15, 2017.
By combining detailed CMAQ simulations of trends in air pollutant concentrations across the U.S. over the past two decades with a health assessment model, this study analyses long-term trends in air pollution associated premature mortality and demonstrates the success of Agency actions, directed at reducing emissions of ambient PM2.5 and O3 precursors, on reducing human exposure to air pollution and improving public health.
The 2015 Global Burden of Disease (GBD) study has listed air pollution as the fourth-ranking global mortality risk factor. Few studies have attempted to understand how these burdens change through time, especially in the United States (US). Here we aim to estimate air pollution-related mortality in the continental US for each year from 1990 to 2016, to understand the trend over this time period. We also analyze the relative contributions of changes in air pollutant concentrations, population, and baseline mortality to the overall trend and to the inter-annual variability in mortality estimates. To achieve this goal, we use a 21-year model simulation of PM2.5 and O3 concentrations from 1990 to 2010, with grid resolution of 36km×36km. We will also use two additional datasets informed by satellite observations: one from the North American Chemical Reanalysis project, which uses OMI NO2 and MODIS AOD observations for data assimilation to constrain ozone and PM2.5 between 2006-2016, and the other from satellite-derived estimates of ground-level PM2.5 using satellite AOD combined with the GEOS-Chem chemical transport model between 1998-2015. For the 21-year simulation, we find that the PM2.5-related mortality burden from ischemic heart disease, chronic obstructive pulmonary disease, lung cancer, and stroke, has steadily decreased, with a reduction of 51% from 1990 to 2010. The PM2.5 -related mortality burden would have decreased only by 27% if the PM2.5 concentrations had stayed at the 1990 level, due to decreases in baseline mortality rates for major diseases affected by PM2.5. The O3 mortality burden has smaller inter-annual variability than the PM2.5-related burden from 1990 to 2010, but the variability for the concentration-change only mortality burden is higher for O3 than for PM2.5. The O3-related mortality burden increased by 12% from 1990 to 2010, despite ozone decreases, mainly due to increases in the baseline mortality rates and population. The O3-related mortality burden would have increased by 61% if the O3 concentration had stayed at the 1990 level. Our preliminary results suggest that air quality improvements have significantly reduced the health burden over the past two decades.