A county-level estimate of PM_2.5 related chronic mortality risk in China based on multi-model exposure data

Ambient fine particulate matter (PM_2.5) pollution is currently a serious environmental problem in China, but evidence of health effects with higher resolution and spatial coverage is insufficient.

This study aims to provide a better overall understanding of long-term mortality effects of PM_2.5 pollution in China and a county-level spatial map for estimating PM_2.5 related premature deaths of the entire country.

Using four sets of satellite-derived PM_2.5 concentration data and the integrated exposure-response model which has been employed by the Global Burden of Disease (GBD) to estimate global mortality of ambient and household air pollution in 2010, we estimated PM_2.5 related premature mortality for five endpoints across China in 2010.

Premature deaths attributed to PM_2.5 nationwide amounted to 1.27million in total, and 119,167, 83,976, 390,266, 670,906 for adult chronic obstructive pulmonary disease, lung cancer, ischemic heart disease, and stroke, respectively; 3995 deaths for acute lower respiratory infections were estimated in children under the age of 5. About half of the premature deaths were from counties with annual average PM_2.5 concentrations above 63.61μg/m³, which cover 16.97% of the Chinese territory. These counties were largely located in the Beijing-Tianjin-Hebei region and the North China Plain. High population density and high pollution areas exhibited the highest health risks attributed to air pollution. On a per capita basis, the highest values were mostly located in heavily polluted industrial regions.

PM_2.5-attributable health risk is closely associated with high population density and high levels of pollution in China. Further estimates using long-term historical exposure data and concentration-response (C-R) relationships should be completed in the future to investigate longer-term trends in the effects of PM_2.5.