Migration testing of bisphenol A (BPA) from low-density polyethylene (LDPE) into food simulants was performed with three factors taken into account: temperature, initial BPA concentration and food simulant type. BPA analysis was carried out by a HPLC-UV method. Fick's diffusion equations were applied to the migration modeling. Diffusion coefficients ( ) and partition coefficients ( ) were determined by fitting the migration curve with the diffusion equation. values obtained under different conditions ranged from 10-10 to 10-8 cm2 s-1. Statistical analysis showed significant effects of all factors on the diffusion coefficient. No interaction effect was shown significant, except for the interaction between temperature and food simulant type. The dependence of diffusion coefficients on temperature followed an Arrhenius type of relationship with the activation energy ( ) ranging from 118 to 134 kJ mol-1 for different food simulants. An exponential relationship was found between the diffusion coefficient and initial BPA concentration for each food simulant. Based on the statistical analysis, an empirical model was developed to express the diffusion coefficient as a function of temperature and initial BPA concentration.
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