Migration of Poly(ethylene terephthalate) (PET) Oligomers from PET Plastics into Foods during Microwave and Conventional Cooking and into Bottled Beverages

Abstract

The migration of total levels of poly(ethylene terephthalate) (PET) oligomers into a diverse range of foods has been determined using an analytical approach that involves hydrolysis of oligomers to terephthalic acid, methylation, and analysis as dimethyl terephthalate by stable isotope dilution GC/MS. Aspects of use of PET materials examined in this study include roasting bags, PET trays (for conventional and microwave oven use), and “susceptor pads” for microwave browning applications. Total levels of migration of PET oligomers were found to range from 0.02 to 2.73 mg/kg depending on the foodstuff and the temperature attained during cooking. On repeated-use of PET trays for heating olive oil there was a decline in migration of oligomers from the first to second and subsequent uses of the container. Migration of oligomers was found to occur at only very low levels from PET bottles into alcoholic and carbonated beverages.