Determination And Risk Assessment Of Plasticizer In Food Of Animal Origin

With the outbreak of food safety incidents of "melamine","clenbuterol" and "plasticizer"etc, food safety has become a hot issue of social concern and solve the problem of food safety is one of the national strategies in China. Phthalic acid esters ?PAEs? is the main additives in food packaging materials, it is easy to migrate from packaging materials to food because of its special valence bond structure and it has a different degree of detection in food and food packaging and harm caused has gradually attracted people's attention.In this paper, we have studied the establishment of ultrasonic assisted-QuEChERS sample pretreatment technology combined with gas chromatography tandem mass spectrometry?GC-MS/MS? to detect 19 kinds of PAEs in food of animal origin ?fish? and provide the basis for the detection of aquatic product packaging safety problems. The main research contents and results are as follows:?1? The optimization conditions of mass spectrometry to determine the parent ion, daughter ions and the optimum collision energy. The temperature of the inlet and the ion source were optimized using full factorial design and central composite experimental design method. Using the analysis of SAS software regression and response surface, the optimum temperature of the inlet and ion source is determined to be 285? and 320 ?, respectively.?2? A pretreatment method for ultrasonic assisted-QuEChERS extraction of phthalic acid esters in fish samples was established. In the extraction process, the recoveries of four kinds of extraction solvents of solvent: acetonitrile ?containing 1% acetic acid? ?acetonitrile: hexane?1:1?, n-hexane, dichloromethane: hexane ?1:1? on target were compared. The results showed that acetonitrile ?containing 1% acetic acid? was the best extraction solvent. To optimize parameters of the ultrasonic temperature, time, power using Plackett Burman ?PB? factorial design, and determine the ultrasonic temperature, time and power were 40?, 30min and 60W,respectively. The single factor experiment was carried out to optimize the extraction solvent volume, and the final solvent volume was determined to be 5mL. Comparing the purification effect of fish interference matrix and the recovery rate of PAEs of primary secondary amine?PSA?, C18 and Al₂O₃-neutral ?Al₂O₃-N?, the results showed that PSA had the best recovery effect. Different amounts of sorbents ?25, 50, 75 and 100mg/mL? were also tested through spiking the blank fish tissues ?5g? of the target mixture, the results showed that 50mg/mL, the recovery efficiency of the target was the optimum.?3? The method was evaluated by linear range, precision and accuracy and 19 PAEs in the range of 10, 20, 50, 100, 200, and 500?g/L have good correlation and the correlation coefficient R2 is greater than 0.99. The method detection limit ?LOD? and method quantitation limit ?LOQ?range from 0.01 to 10[?g/kg and 0.05 to 20?g/kg were obtained. Three level spiking experiments ?20, 50, 200?g/kg t? showed recoveries from 71.22% to 116.29% for 19 PAEs with relative standard deviation range from 3.91% to 16.02%. The accuracy and precision of the method were consistent with the requirements of residue analysis.?4? The method established was analyzed and evaluated to phthalate esters in fish samples.The results found that DEP, DBP, DIBP and DEHP were detected in fish samples. The content of 4 PAEs range from 0.53?40.59?g/kg, which is lower than the allowable maximum residue limit standard in our country, indicating that it is harmless to human health.