[Distribution, source and risk assessment of polycyclic aromatic hydrocarbons in river sediment of Cheng-Yu economic zone].

The USEPA 16 priority pollutant dominated polycyclic aromatic hydrocarbons (PAHs) in the surface river sediments of Sichuan Province and Chongqing City in southwest China were determined using GC-MS. The result showed the content of PAHs in the sediment ranged from 48.2 ng/g to 723.1 ng/g, with an average value of 276.1 ng/g. Among which, the maximum content was found in Shimenzi of Yangtze River, the minimum content was found in Baiqing of Fujiang River. The content order of PAHs in the sediments followed Yangtze River (358.6 ng/g) > Minjiang River (322.2 ng/g) > Tuojiang River (292.7 ng/g) > Qujiang River (260.6 ng/g) > Jialing River (240.2 ng/g) > Fujiang River (82.4 ng/g). The vertical profiles of c(An)/c(An + Phe), c(FlA)/c(FlA + Pyr) and c(InP)/c (InP + BghiP) suggested the PAHs in this zone were mainly originated from pyrogenic source, the main sources of PAHs were petroleum combustion, biomass combustion, and coal burning. Risk assessment suggested that the PAHs in the sediment of this zone had no significantly biological impairment and low toxicological risk.