The Migration Research And Detection Of Organic Contaminants In Food Packing Plastic Material

In this paper, the determination methods of7residual monomers in acrylonitile-styrene plastic by gas chromatography with head space sampler or solid-phase micro-extraction (SPME) and8phthalic acid esters by liquid chromatography with SPME were optimized. In addition, the migration patterns of7residual monomers and8phthalic acid esters from acrylonitile-styrene plastic to4food simulants were also studied. The main results were summarized as follows:(1) The optimum condition for the determination method of7residual monomers in acrylonitile-styrene plastic by gas chromatography with head space sampler was obtained:the usage of solvent3mL, the heating temperature120℃, the equilibrium time40min. The average recoveries of7residual monomers were between95.71%and106.89%, and the detection limits were between0.5～1.0mg/kg. The developed determination method has many advantages, such as simple, rapid, accurate, and sensitive.(2) The optimum extraction condition for determination method of7residual monomers in acrylonitile-styrene plastic by gas chromatography with SPME was obtained: the elected extraction head was PDMS, the extraction temperature was60℃, the extraction time was30min. The average recoveries of7residual monomers were between96.06and107.91%, the detection limits were between0.25and0.75mg/kg. The relative deviation is less than0.82%(the standard addition level was10mg/kg、50mg/kg, and500mg/kg, respectively).(3) The optimum determination condition for8phthalic acid esters in acrylonitile-styrene plastic by HPLC with SPME was obtained:gradient elution was employed, the pretreatment used ultrasonic extraction, the elected of extraction head was PDMS/DVB, the extraction time was30min. The average recoveries of8phthalic acid esters were between84.91and106.60%, the detection limits were between0.1and10mg/kg. The relative deviation is less than2%(The standard addition level was10mg/kg、50mg/kg, and500mg/kg, respectively).(4) The migration patterns for7monomers and8phthalic acid esters in4different kinds of food simulants (water,3%acetate,20%ethanol and n-hexane) were obtained:the migration amount of7residual monomers is larger in the polarity of the smaller simulate fluid than in the polarity of the larger simulate fluid; the migration of fluid amount for the low polarity of DEHP, DINP and DIDP from8phthalic acid esters is significantly greater in the fatty food analog soaking liquid (n-hexane) than the amount of migration in the other five phthalates, The polarity of the larger for phthalate showed the larger amount of migration in aqueous food (upw), acid food (3%acetic acid aqueous solution) and alcohol (20%ethanol aqueous solution). The immersion time and the immersion temperature with7residual monomer and8phthalic acid esters have certain proportional relationship in the migration amount.