An extensive literature review has pointed out knowledge gaps about the migration of polyethylene terephthalate (PET) oligomers from food contact materials (FCMs) into foods, as well as inadequate risk assessment for the chemicals.
Oligomers are small molecules made of just a few repeating polymer units. The goal of the study was to identify and organize existing knowledge of hazard and exposure data on 34 PET oligomers. To do this, the authors sorted published information, found in the Food Packaging Forum’s database on Migrating and Extractable Food Contact Chemicals (FCCmigex), into different evidence categories to fully record all available hazard and exposure data.
Data from FCCmigex, which is based on over 800 scientific publications on plastic FCMs, revealed a total of 74 percent of the 34 oligomers were prone to migrate. Of the chemicals found to migrate, 38 had in silico toxicological predications, and only one oligomer had been tested for safety in vitro.
While the very limited safety testing data do not point to major concerns, they are also severely limited in scope and have not checked for impacts on most health endpoints. Additionally, the findings undermine the assumption that PET oligomers are completely hydrolyzed, which has previously been used as a rationale to only assess the risks of respective monomers.
Based on the literature, the researchers emphasize the importance of developing more systematic and tiered approaches to address the identified research needs and assess the risks of PET oligomers.
The study was led by scientists from the University of Basel, Switzerland, and was co-authored by scientists from six other institutions, including the Food Packaging Forum.