Occurrence And Distribution Of Perfluorinated Compounds In Typical Pollution Sources And Groundwater In The Pearl River Delta

Perfluorinated Compounds (PFCs) are widely used in life, industry and scientificresearch products due to their unique surface activity and chemical stability. Thesebioaccumulation and toxicity compounds are new type of persistent organic pollutants, havestable property and can migrate long distance. There are many research on the pollution levelsof PFCs in surface water, sediments and organisms at present, but the research of distributionof PFCs in groundwater is still rare and yet little research on the concentration of PFCs intypical pollution sources, such as landfill leachate, wastewater treatment plant and citysewage river. Therefore the investigation of distribution and concentration of PFCs in thetypical pollution sources and groundwater is necessary.By establishment an pre-trestment and analysis methos of PFCs, this paper analyze theconcentration and distribution of PFCs in the wastewater treatment plant,landfill leachate,and the typical pollution river in the Pearl River Delta area, and investigate the situation ofPFCs pollution in urban and suburbs groundwater in this region. Following are theconclusions:(1) The target compounds include9kinds of perfluoroalkyl carboxylic acids,2kinds ofperfluoroalkyl sulfonic acids, and2kinds of perfluoroalkyl Amides. The study verified anddeveloped the pre-treatment method of PFCs in water, soil and sediments, which wereanalyzed by liquid chromatography-tandem mass spectrometry. The solid phase extractionwas employed as the pre-treatment method of water sample, using WAX as extraction column.Ultrasonic extraction and solid phase extraction was used as the extraction and purificationmethod of PFCs in soil and sediment. Internal standard was used in the quantification. Thedection limits are ranged from0.9to21.1ng/L. The Recoveries range of water, sediment andsoil are58.7-129.5%,87.1-135.8%, and71.2-142.8%. The relative standard deviations are1.17-21.9%. The method detection limits range of water, sediment and soil are0.015-0.054ng/L,4.2-743ng/kg and12.4-875ng/kg, respectively. The method detection limits, accuracy,and precision are suitable for the requirements of trace analysis.(2) The concentrations of PFCs in wastewater treatment plant, swage and landfillleachate are at high levels in the Pearl River Delta area. The landfill leachate of Guangzhouand Shenzhen are with high concentrations of PFCs, which are735.4ng/L and338.2ng/L, respectively. PFOA, PFOS and Perfluoro-n-nonanoic acid (PFNA) are the main pollutants. Inthe six wastewater treatment plants, the∑P s on entrations in the effluent are ranged from2.75to94.58ng/L, and the main PFCs component are perfluorooctane acid (PFOA) andperfluorooctane sulfonate(PFOS). In sludge the∑P s on entrations are ranged from6.56to26.68ng/g, PFOS is the main PFCs component. In Guangzhou typical polluted river, the∑P s on entrations are9.5to17.6ng/L in water samples, and0.65to7.6ng/g in sediment,dry weight. The main target component are PFOS and PFOA.(3) In the36groundwater samples taken from Guangzhou, Zhongshan, Shenzhen,Dongguan and Qingyuan in the Pearl River Delta area. The detection rate of PFCs in thesesamples is100%. In the groundwater samples∑P s on entrations range from0.056to54.07ng/L, and the mean concentration was6.69ng/L. the concentrations of∑P s ingroundwater in5citys follow the order of: Dongguan> Guangzhou> Zhongshan>Foshan>Qingyuan. In groundwater, the main target pollutants are the short carbon chainperfluorinated carboxylic acid and sulfonic acid, and the long carbon chain compounds have alow detection rate. There is a significant correlation (P<0.05) among the PFCs concentrationsin all groundwater samples from the Pearl River Delta area. Indicating that these compoundshave similar pollution soureces.The results of this thesis are helpful to the knowledge of concentrations and pollutionstatus of PFCs in typical pollution sources and groundwater in the Pearl River Delta. Theresults also provide data support for the risk assessment and source apportionment of PFCs ingroundwater, and suppose the scientific basis for pollution control of the PFCs.