Distribution And Sources Of Persistant Organic Pollutants In Aquatic Environment Of Lake Taihu

The long-term existence of POPs in the world is a great threat to both human beings and the ecosystem, due to their toxic properties, non-degradable, bioaccumulative and ability to transport and deposit far from their places of release. In this study, occurrence and distribution of PAHs, OCPs and PFCs in Taihu Lake were investigated, and their sources as well as environmental and ecological risks were assessed. Two sampling campaigns were conducted in May 2010 and Sep 2010, respectively, with a total of 41 samples of overlying water, porewater and sediment collected. PAHs and OCPs were analyzed by GC-MS and PFCs were analyzed by LC-MS-MS. The following results were obtained.The sediment PAHs in Lake Taihu originated from both pyrolytic and petrogenic sources, showing a mixed input pattern. Based on the numerical effect-based sediment quality guidelines (SQG) of the United States, the sediments from Lake Taihu causing adverse effects by PAHs should have potential biological impact, but should have no impairment.Concentrations of OCPs obtained in September 2010 were higher in overlying water but lower in porewater and sediment compared with those in May 2010. This may be due to the high temperature in May. High temperature is favorable for the release of OCPs from sediment to solution.Results show that concentrations of PFCs in September 2010 were lower than in May 2010, which may be related with the pollution control from sources.