Distribution characteristics of polycyclic aromatic hydrocarbons and black carbon in road dusts from typical cities of China and India

In order to investigate the distribution characteristics of polycyclic aromatic hydrocarbons(PAHs) and black carbon(BC) in road dusts in typical cities of Beijing,Shanghai,Guangzhou and Wuhan in China and Kolcata in India,samples were collected in urban roads during Dec.,2007 to Feb.,2009.The total 16 PAHs concentrations in metro cities from China were 2.30-22.2 μg·g-1,which was dominated by FLA,PHE,PYR,CHR,BBF and BGP.PAHs contents were in the range of 4.85-30.5 μg·g-1 in Kolcata from India,which was dominated by NAP.Higher levels of BC in Chinese cities than India city were likely due to different power structures and consumes.The correlation between PAHs and BC showed different characteristics in different city,which might be reflected diverse sources.Diagnostic ratios demonstrated that the main source of PAHs was from the emission of vehicle,and coal combustion is another possible source.