Migration of conventional and new plasticizers from PVC films into food simulants: a comparative study.

摘要

PVC is one of the resins with the higher quantity of additives and the possibility of migration is always a concern when its intended use is food packaging. In this study, the migration of several plasticizers was investigated with the aim of finding out a relationship between migration and conformance with legislation in force, and tensile properties as well. Therefore, six PVC cling films intended to come into contact with foodstuffs have been formulated in order to have same hardness and thickness. The reference film was produced with DEHA and ESBO, while the other films were produced with conventional plasticizers (ATBC and Polyadipate), new plasticizers from renewable resources (Mixture of glycerin acetates - MGA and Acetic acid esters of mono- and diglycerides of fatty acids - AGM) or a plasticizer employed in toy and childcare applications (DEHT). The films were evaluated as to the overall and specific migration to food simulants and the effect of the formulation was studied. The results have shown that the coefficient of apparent partition of DEHT is similar to that of DEHA, whereas MGA and AGM plasticizers displayed higher coefficients of apparent partition than the other plasticizers under study. This difference in migration has been attributed to the different molecular structures of plasticizers. In addition, commercial films have been evaluated as to plasticizers concentration and specific migration into food simulants. It was found that 25% of the samples comply with the specific migration limits for fatty foods contact while 50% might be used for contact with fatty foods with FRF 2-5. On the other hand, all commercial samples showed no restriction for aqueous acidic food contact. Thus, it has been demonstrated that a contact for prolonged time up to 40 degrees C did not promote the migration of plasticizers into acidic foodstuffs, but the migration of plasticizers to fatty foods can be high (75%-90% loss of plasticizers) and limit the use of PVC films as fatty food packaging