Distribution and ecological risk of polycyclic aromatic hydrocarbons in sediments of Chongming Island grass carp ponds

In order to investigate the polycyclic aromatic hydrocarbons pollution of pond aquaculture in Chongming Island, the contents and distribution of 16 PAHs in the sediments of 10 grass carp ponds in different areas of Chongming Island were analyzed by GC-MS. The sources of PAHs in ponds in different areas were analyzed by principal component analysis and characteristic ratio method. At the same time, the ecological risk was evaluated by sediment quality standard method and quality standard method. The results showed that the total PAHs content in the aquaculture sediment of grass carp pond in Chongming Island ranged from ND to 1 654.09 μg/kg, with an average content of 95.13 μg/kg, of which the contribution rate of PAHs in the 4-5 rings was high; the PAHs content in the sediment of grass carp pond in different areas of Chongming Island was quite different, the content of pond in the middle of island was low, and the content of pond around the island was high, especially in the west coastal area of of Chongming Island. PAHs mainly come from biomass combustion and oil combustion, which are generally at the lower middle pollution level, and the ecological risk is low, but there are potential ecological risks in the ponds along the west coast of the island, which should be paid attention to.