Study On Analysis Methodology Of Perfluorinated Compounds In Edible Oil And Its Application

Perfluorinated compounds were widely used in lubricant, surfactants, food packaging and coating layer of nonstick pan. As a new kind of persistent organic pollution, PFCs, especially PFOS/PFOA, were detected in environmental media, organisms and human body these years. The toxicity and adverse effects of PFCs of hepatotoxicity, developmental toxicity, immune-toxicity, hormonal effects and carcinogenic potency have been confirmed. Furthermore, it can interfere internal secretion, change the instinct of the animal behavior and may have potential developmental Neurotoxicity to infants.An innovative method for analyzing trace levels of 18 PFCs, including C4-C14 perfluorinated carboxylic acids(PFCAs), C4-C10 perfluorinate sulfonates(PFSAs), C8 Perfluorinated octyl sulfonamide(PFASs) and five kinds of isotope internal standards in edible oil samples was established. The pollution level of PFCs in from Beijing market as well as crude and refined oil from different processing technic were also researched. Results are summarized as follows:(1) An innovative method was established for the simultaneous detection of PFCs by liquid chromatography-tandem mass spectrometry(LC-MS/MS). The purification effects of PFCs from edible oil were evaluated using gel permeation chromatography by collecting the distillate at different time segmentation. And the effects of three DSPE sorbents were also evaluated. The average recoveries of all target PFCs were from 74.2% to 129.8% in edible oil and the relative standard deviation were lower than 17.4%. The method detection limits were ranging from 0.004 ?g/kg to 0.4 ?g/kg.(2) The pollution level of PFCs in edible oil from markets in Beijing was researched. Seven kinds of PFCs, mainly PFNA, PFHxA and PFOA, were detected with concentration ranging from ND-4.64 ug/kg、ND-0.488 ug/kg and 0.129-0.504 ug/kg, respectively. Dietary risk assessment showed that the pollution level and dietary exposure were both in an acceptable level.(3) Concentration of crude oil of peanut, soybean and sesame was researched. We found that the concentration of PFCs were lower than that in raw materials, howerer, obviously higher that in brand vegetable oil, as well as their type. Through frying and steaming following with crushing and pressing process, the concentration of PFCs of long chain decreased, and the concentration of PFOS, PFOA increased, with a high detection rate. And the concentration of PFCs in crude oil were far lower than that in the bean dregs.(4) Refined oil from five oil plants were researched and the dynamic variation were concluded as follows. The detection rates of PFCs in refined oil were generally low, so that the damage to human was little. Deacidification and decoloration technique may introduce some kinds of PFCs, which indicate that they should be the critical control points. The whole refining process can remove PFCs well. On the other hand, High concentration of PFCs in phospholipids concentrate were detected, especially the PFCs of carbon chain length below 12.