Size-differentiated patterns of exposure to submicron particulate matter across regions and seasons in China

摘要: Abstract Air pollution in China has reached unprecedented levels due to rapid economic and industrial development. More than 90% of Chinese population experience higher health risks attributable ambient fine particulate matter (PM2.5) exposure. Although evidence suggests that particle size may be an effect modifier on PM2.5-related risks, few studies have explored this lack size-resolved exposure data. In study, we derive effective radius PM2.5 using theoretical relationships between aerosol microphysical characteristics satellite optical measurements explore the spatial variability size. Applying method 2017, observed annual mean radii 0.3 1.3 μm with a average error 0.1 μm. We find 1% or less was exposed concentrations 10 μg/m3 greater 0.7 μm (i.e. aerodynamic diameter PM1). Spatially, Centre region had highest annual-mean exposures, where 50 μg/m3 98% particles below 0.5 μm. Temporally, although were more likely occur winter, summertime season during which percentage national (86%) lived regions fraction smallest (