Study On The Organic Pollution Status And Source Apportionment Of PCBs In Water And Sediment Of BaiHua Lake

The paper summarizes propeity,sources,distribution and behavior and fate of polychlorinated biphenyls(PCBs),and introduces behavior and fate of PCBs in the lake(environment).The PCBs of Aroclor1242,Aroclor1248,Aroclor1254 and Aroclor1260 which are produced in ARCOLOR company were used as the goal pollutant in order to study the content and distribution of PCBs in water and the sediment of the BaiHua Lake.The main conclusions have been reached as followings:1.A sensitive,rapid and accurate method for extraction and determination of PCBs from samples has been developed by modification of conventional method in this study.This method is only based on solid-phase microextraction(SPME) for water samples;ultrasonic extraction (UE) and purification by silica gel for sediment samples,in the meantime, PCBs were pretreated with soxhlet extraction(SE),PCBs were analysed by gas chromatography with electron capture detection(GC-ECD) mode.the results with the different methods showed that ultrasonic extraction is better than soxhlet extraction.2.The variation characteristics of composition and concentration of PCBs in water and sediment of BaiHua Lake:Total PCBs which types is Aroclor1260 concentration range from Oμg/L to 0.018 ug/ml in water,and total PCBs which types are Aroclor1254 and Aroclor1260 concentration vary from 0.0072 to.0.0013 mg/kg and 0.0038 to 0.0114 mg/kg in surface layer of sediment.3.The article introduce the PCBs pollution's history of BaiHua Lake. It is discerptible of 2 phases:1978-1988 year(10-15cm) is high-content phase;1988-2008 year(0-10cm) is extent fluctuant and rising phase, The result also showed that the PCBs types in the sediment samples have changed.4.In the article,the main source of PCBs in the water and the sediment of the BaiHua Lake were the produce of atmospheric dry and wet precipitation and people production and exist,such as the combustion of mineral and fossil fuel,exhaust gas of burning rock oil,liquid waste.5.the total PCBs concentrations had been compared with the routine indexes of BOD₅.The result of analysis indicated that there was no relativity between BOD₅ and the total PCBs,therefore it could not reflect the status of PCBs pollution.It need add either monitor of organics or some toxicity experiments.