In this paper

a method is established to quantitatively partition fractional contributions of polycyclic aromatic hydrocarbons（PAHs） in fine atmospheric particulate matters by using stable carbon isotopic analysis. Dichloromethane extraction

TLC purification

and gas chromatography-combustion system and isotope mass spectrometry（GC/C/IRMS）

are used to measure the stable carbon isotope compositions(δ

13

C).The fractional contributions of coal combustion

vehicle exhaust and biomass burning to the PAHs in the fine particulate matters (PM

2.5

) collected in Jiading district

a suburb of Shanghai

are estimated.The results show that theδ

13

C values increase with decreasing molecular weight.The coal combustion and biomass burning play bigger role than vehicle exhaust in the PAHs

compared to theδ

13

C values of PAHs in all kinds of potential pollution sources.The estimated contributions from coal combustion

vehicle exhaust and biomass burning to PAHs of PM

2.5

range from 3%- 21%

29%- 33%and 46%- 67%

respectively

which agree well with the surrounding condition of the sampling site

indicating that it is feasible to estimate the fractional contributions of PAHs quantitatively by using stable carbon isotopic analysis.