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Particulate matter(PM)concentrations and characteristics are of concern in China due to severe atmospheric pollution under the accelerating economic development.Statistic analysis from published data in parallel PM2.5 and PM10 mass concentrations and chemical species in PM2.5 and PM10 were carried out in order to give a PM profile and further PM evaluation in China when the revised particulate standard was approved in 2012.The results show that most of measured concentrations far exceed annual averages of 35 μg/m3 for PM2.5 and 70 μg/m3 for PM10 in the revised standard(Grade-Ⅱ,GB3095-2012).PM levels vary greatly across the country with values of 8.77-500.25 μg/m3 for PM2.5 and 22.5-743 μg/m3 for PM10,which are much higher than those in American(2-27 μg/m3 and 2-35 ug/m3 for PM2.5 and PM10,respectively)(Eldred et al.,1997)and European(7-39 μg/m3 and 8-55 μg/m3 for PM2.5 and PM10,respectively)(Querol et al.,2004).There are higher PM mass concentrations in northern than those in southern China.PM2.5 and PM10 mass concentrations have a strong correlation(R2=0.87,p<0.01)with a dominated fraction of PM2.5(0.65)across the country,suggesting the abatement of PM2.5 is crucial to contribute low PM level and better air quality.The ratio and correlation of PM2.5 to/and PM10 in southern China(0.68,R2=0.93,p<0.01)are higher than those in the north(0.61,R2=0.80,p<0.01).Furthermore,there are less variation and higher values in ratios and correlations of PM2.5 to/and PM10 in temporal and spatial patterns in the south compared to those in northern China.The distinct PM characteristics may be attributed to different formation and sources of PM2.5 and PM10 and the discrepancies in energy consumption,which mainly derive from industrial types,and climate in the two regions.Organic carbon(20.0%±6.0%),sulfate(19.5%±7.6%)and crustal species(11.7%±10.1%),and crustal species(26.9%±16.5),organic carbon(16.5%±6.8%)and sulfate(15.6%±6.1%)are the three most major components in PM2.5 and PM10,respectively,in China.The ratios of NO3-/SO42-are 0.43±0.26 in PM2.5 and 0.56±0.29 in PM10,signifying stationary source emissions from coal combustion are still the main source of PM.The OC/EC ratios of 3.63±1.84 in PM2.5 and 4.05±2.17 in PM10 imply the possible presence of second organic aerosol,which can occupy 56.7%of OC in PM2.5 and 11.5%PM2.5 mass.PM2.5 situation in current China were evaluated based on above analysis.The results show that it is about 27 years to meet the limit value of 35 μg/m3 in the revised standard,and meanwhile,the emissions of SO2,as the precursor of major component SO42-in PM2.5,should be cut to 4.28 Tg from 21.85 Tg(in 2010).These will progress under a relative fast economic increase in China (over 10%GDP growth rate),signifying a rigorous challenge in PM pollution control in the future.