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Title: Reversal of trends in global fine particulate matter air pollution
Abstract Ambient fine particulate matter (PM2.5) is the world’s leading environmental health risk factor. Quantification is needed of regional contributions to changes in global PM2.5exposure. Here we interpret satellite-derived PM2.5estimates over 1998-2019 and find a reversal of previous growth in global PM2.5air pollution, which is quantitatively attributed to contributions from 13 regions. Global population-weighted (PW) PM2.5exposure, related to both pollution levels and population size, increased from 1998 (28.3 μg/m3) to a peak in 2011 (38.9 μg/m3) and decreased steadily afterwards (34.7 μg/m3in 2019). Post-2011 change was related to exposure reduction in China and slowed exposure growth in other regions (especially South Asia, the Middle East and Africa). The post-2011 exposure reduction contributes to stagnation of growth in global PM2.5-attributable mortality and increasing health benefits per µg/m3marginal reduction in exposure, implying increasing urgency and benefits of PM2.5mitigation with aging population and cleaner air.  more » « less
Award ID(s):
2019494
PAR ID:
10553362
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Nature
Date Published:
Journal Name:
Nature Communications
Volume:
14
Issue:
1
ISSN:
2041-1723
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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