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Polyvinyl chloride (PVC) is a polymer compound by the polymerization of vinyl chloride monomer, add the plasticizer, stabilizer and the like made of a polyvinyl chloride film of high transparency, high strength, and good withstand low temperature, self-adhesive , oxygen permeability and water vapor transmission capability, you can keep the food fresh. PVC film production process will add a lot of plasticizer, there will stabilizers, solvents, residual monomer, these substances on the human body has a variety of hazards, PVC film for packaging food products is unsafe. Although China has been limiting the portion of the field of PVC film for food packaging, but because of the excellent features and low price of PVC film, is still a large number of food market use. At the same time due to poor oversight, market, street do use recycled plastic PVC film or unclear purpose PVC film costumes food. For food packaging with PVC film / cap washer identified film evaporation residue content was measured; analysis film chloride monomer, solvent benzene and toluene, antioxidants bisphenol A, and a plasticizer were established o-dioctyl phthalate and dibutyl phthalate butyl measuring method, and the film of these substances migrate to the food research to understand Harm Situation of food packaging polyvinyl chloride film and packaging various types of food security risks, to provide a reference basis for the production of regulatory authorities. Test first food packaging with PVC film identified, measured the film evaporation residue content. Dissolution - precipitation method to dissolve the film sample polyvinyl chloride, extracted with tetrahydrofuran, and ethanol as a precipitating agent, so that the separation of PVC and a plasticizer, eliminating interference. Fourier transform infrared spectroscopy, scanning wave number 4000 500 cm-1, detection of the 26 kinds of films for food packaging field samples collected from the market, identified nine kinds of PVC film material. The evaporation residue test results show that nine kinds of PVC film evaporation residue are in line with the national standard hygiene requirements. Secondly, the manual headspace injection gas chromatography detection PVC film, vinyl chloride monomer. The test parameters of gas chromatography and sample equilibrium conditions are optimized, select in the a 70 ℃ balance 30min using the DB-WAXtre polar capillary GC column separation, hydrogen flame ionization detector FID detector, vinyl chloride monomer in the 0-4.977μg within the linear range of R2 = 0.9994 detection limit 0.199mg/kg. Vinyl chloride monomer spiked recoveries between 91.04% -103.27%, and the relative standard deviation RSD (n = 3) 3.76% -4.50% meet PVC film monomer residue analysis method. Were not detected residual vinyl chloride monomer nine kinds of PVC film, PVC film for food packaging, vinyl chloride monomer residues to some extent that is not serious. In this study, using gas chromatography detection PVC film and food (apple fritters / fried dumplings, beer), benzene and toluene. The most widely used method of using HP-5 silica GC column separation, hydrogen flame ionization detector FID detector, benzene and toluene in the linear range 0.866-86.600μg/mL 0.88-88.00μg/mL, has a good line The sexual relations R2 were 0.9995 and 0.9992, the detection limits were 0.220μg/mL and 0.216μg/mL. Benzene and toluene spiked recoveries between 69.88% -87.55%, RSD (n = 3) 1.86% -4.98%. Methods to meet the analysis of benzene and toluene in PVC film and apple fritters / fried dumplings, beer residues. Simultaneously measured residual benzene and toluene, nine kinds of PVC film, PVC film, benzene and toluene in the apple fritters / fried dumplings, beer migration. Nine kinds of PVC film 3 detected benzene residue, five kinds detection toluene remained, the two kinds of samples at the same time detection of benzene and toluene, the residual amount is far less than provisions of EU toluene. Migration Test found in the film samples have not been detected in the benzene / toluene packaging foods also not detected benzene / toluene; beer sample was not detected in the benzene and toluene; use in the detection of the benzene / toluene film sample packaging corresponding food Apple not detected benzene and toluene, fritters / fried dumplings in the migration of benzene and toluene and packaging film in both content and packaging time-related, may also be associated with the film production process or the size of the gap structure factors; toluene the fritters / Jianjiao trial the migration within the provisions of the EU 0.880-1.168mg/kg benzene migration 0.883-1.024mg/kg is much higher than the required targets of the European Union. Test using high performance liquid chromatography PVC film and packaged food (apple fritters / fried dumplings, beer), bisphenol A the analysis, bisphenol A in 0.0001-0.5mg/mL and 0.0001-0.05mg/mL good range of linearity, R2 of 0.9990 and 0.9999, respectively. The sample extraction method selection optimization, to determine the film with the V (dichloromethane): V (methanol) = 9:1 ultrasonic extraction 30min, apples, the fritters / Jianjiao, beer respectively by V (dichloromethane): V ( methanol) = 7:3, V (dichloromethane): V (methanol) = 9:1, V (dichloromethane): V (methanol) = 6:4 ultrasonic extraction 1H. Spiked recoveries 85.15% -100.02% precision (n = 3) 1.17% -4.72%, PVC film, apple fritters and beer samples bisphenol A detection limit of 0.01mg/kg, 0.02mg/kg , 0.02mg/kg and 0.01mg / L. Simultaneous determination of bisphenol A migration to the food content of bisphenol A nine kinds of PVC film and PVC film. 9 kinds of PVC sample, four detection bisphenol A content 20.823-49.125mg/kg. Also found in the film samples packaged food has not been detected bisphenol A migration test were not detected bisphenol A; detected bisphenol Apple A0.403mg with film samples detected bisphenol A corresponding packaging food packaging 4 months / kg, packaging 60min fritters and Jianjiao of detection of bisphenol A were bisphenol A content 0.109mg/kg and 0.079mg/kg, bisphenol A migration packaging film, packaging time, temperature; migration relatively safe. Perfect and innovative PVC film and food (apple fritters / fried dumplings, beer) solid-phase extraction and high performance liquid chromatography analysis method of DnOP and DBP in this study on the basis of previous studies. DnOP and DBP, respectively in 9.8 × 10-6-0.0098mg/mL, and 5.235 × good linearity in the range 10-6-0.01047mg/mL the, R2 is 0.9994 and 0.9997, respectively. Choose to optimize conditions of sample extraction and purification methods found better than using a single column and Florisil column (2) combined with the purification enrichment using activated carbon column (1), and the film crude extract and Apple crude extract in DnOP and DBP detection limit by two column purification 8.3-10 times the finalized film extracted with hexane ultrasound for 30 min, apples, the fritters / Jianjiao, beer respectively V (acetone): V (n-hexane) = 1:3, V (acetone): V (n-hexane) = 1:3, V (acetone): V (n-hexane) = 1:4 ultrasonic extraction for 1 h extract first column, eluting with 5mL of dichloromethane, another column purification, with 5 ml of V (acetone): V (n-hexane) = 1:4 elution, dried with nitrogen and set the volume measured. Recoveries DnOP and DBP 82.24% -105.39% precision (n = 5) 1.08% -9.67%, the detection limit between 0.00465-0.02616mg/kg meet PVC film and apple fritters / fried , the beer in DnOP analysis and DBP. Simultaneous determination of the content of the nine kinds PVC film DnOP and DBP, and PVC the film DnOP and DBP migrate to food. Nine kinds of PVC samples, six kinds of detection DnOP detection DBP, the three kinds of detection DnOP and DBP; meet the requirements of the EU to DnOP and DBP limited only 4. Migration Test not been found in food packaging film sample detection DnOP / DBP and not detected DnOP and DBP; detected DnOP / DBP film samples corresponding packaging food, packaging four months Apple detection content is the highest DnOP 0.3230mg/kg, the fritters / Jianjiao of packaging 60min measured the highest content migration DnOP 0.3852mg/kg, DnOP and DBP packaging film in both content and packaging time, temperature, may also be related related to the nature of the food, and the production process of the film; the migration 0.3383mg/kg fritters measured DBP has already exceed EU specified migration limits 0.3ppm. Recommended in accordance with the relevant national daily tolerated dose of bisphenol A 0.01mg/kg body weight d, DnOP of 0.05mg/kg weight · d DBP 0.05mg/kg body weight · d, the results showed little risk of contaminated food. Further, the bisphenol A and plasticizers DnOP, the dissolution test show that the amount of the dissolution of both increased with immersion time, and also the kind of the solution with food simulation measured bisphenol A in n-hexane, 4% acetic acid, 20% ethanol and maximum dissolution in water for 20.0044mg/kg 4.9210mg/kg, 0.7512mg/kg) .6714mg/kg; the measured DnOP maximum dissolution amount n-hexane 51.9358mg/kg, the in edible oil, 4 % acetic acid, 20% ethanol and 10% salt elution amount 41.2482mg/kg, 9.0854mg/kg, 6.6990mg/kg and 6.4748mg/kg, while the amount of the maximum dissolution in water only 2.1340mg/kg. The results showed that both fairly easy to migrate from PVC film into fatty foods, pickled products, alcoholic beverages, acidic foods there are relatively large risks, consumers also try not to use PVC cling film packaging material fats and oils, especially high temperature snack food, or as soon as possible after eating.
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