Study On Enrichment And Determination Methods Of Persistent Organic Pollutants And Health Risk Assessment Of Perfluorocarboxylic Acid

Polycyclic aromatic hydrocarbons and perfluorocarboxylic acids are persistent organic pollutants,which have carcinogenic,teratogenic and mutagenic effects.Long–term exposure to the environment will threaten the health of people.Therefore,monitoring the content of persistent organic pollutants in the environment is of great significance.Aiming at the problem of extremely low levels of persistent organic pollutants in the environmental water and the complexity of the matrix,this study intends to deve lop an efficient,rapid,and sensitive detection method based on the sample pretreatment technology of the new adsorbent material.And the established methods were used to determine the exposure levels of persistent organic pollutants in environmental water and drinking water in Baoding area,And a risk quotient?HQ?was used to assess the health risks of perfluorinated compounds in drinking water in Baoding city.The main research contents are as follows:?1?A pipette tip solid phase extraction technique?PT–SPE?based on molybdenum disulfid–ethylenediamine–hypercrosslinked polymer composite?MoS₂–EDA–HCP?was established for the analysis of polycyclic aromatic hydrocarbons?PAHs?in environmental water.The composites were characterized by scanning electron microscope,infrared spectrometer and specific surface area meter and thermogravimetric analyzer.The results showed that the surface of the composite is poor porosity holes and has abundant adsorption sites?electrostatic interaction,?interaction and hydrophobic interaction?.The synthesized composite was used as an adsorbent for PT–SPE.And combined with HPLC–FLD fluorescence detector,the highly efficient and sensitive determination of PAHs?phenanthrene,anthracene,fluoranthene,pyrene and benzo???anthracene?in environmental water was achieved.Under the optimum extraction conditions,the method has a wide linear range(0.5–100 ng mL^-1)and low limit of detection(0.024–0.099 ng mL^-1),and the recoveries of PAHs from spiked environmental water were 73.8%to 123.6%?relative standard deviation?6.7%,n=3??2?A new method for the determination of trace perfluorocarboxylic acid?PFCAs?in environmental water was established by using stripped fluorinated graphene?FG?as a tip solid phase extraction adsorbent,combined with pre-column derivatization and gas chromatography-mass spectrometry?GC–MS?.The stripped fluorinated graphene is characterized by scanning electron microscope,infrared spectrometer and specific surface area meter.The results showed that the material has a lamellar structure and the structure is stable.Due to the strong F–F force between FG and PFCAs,it has the advantages of high adsorption efficiency and high sensitivity when it is used to enrich trace PFCAs in water samples.The method has good linear range of 0.001–100 ng mL^-1?correlation coefficient?0.999?and low detection limit are 0.17 ng L^-1,2.22 ng L^-1 and 2.30 ng L^-1.Under the optimal extraction conditions,the recoveries are between 87.2%–110.2%?relative standard deviation?11.2%,n=3?.It is successfully applied to the determination of perfluorocarboxylic acids in environmental water samples in Baoding area,and the content was detected between ND–32.31 ng L^-1.?3?The content of PFCAs in 32 drinking water samples collected from Baoding area are analyzed by the established PFCAs determination method.The results showed that the content of?PFCAs in drinking water in Baoding area is 1.44–21.45?ng?L^-1,in which perfluorooctanoic acid?PFOA?is the main component.The average daily intake of?PFCAs for adults and children is calculated by the range of 0.044 ng kg^-1 d^-1–0.654 ng kg^-1 d^-1 and0.074 ng kg^-1 d^-1–1.099 ng kg^-1 d^-1,respectively.PFOA is the main ingested compound,accounting for 51.27%of the average daily intake of?PFCAs.The calculated HQ of PFCAs is accounting for 51.27%of?PFCAs ADI.The calculated HQ of PFCAs is 0.0080–0.1191for adults,0.0036–0.0551 for children respectively,and HQ are all less than 1.0,indicating that the current health risks of PFCAs in Baoding area are relatively low,however,due to the strong accumulation capacity of PFCAs in the environment,and the health risks caused by long-term exposure to PFCAs environment still deserve common attention.