Occurrence and migration of non-intentionally added substances in raw and finished PEEK-based food contact materials via suspect screening and risk prioritization

Advanced food contact materials (FCMs) face critical safety challenges from non-intentionally added substances (NIAS) whose origins and migration remain poorly understood. Here we establish an integrated suspect screening and risk prioritization framework to unravel NIAS formation, migration, and toxicological significance in two polyether ether ketone (PEEK)-based FCM systems. Using UPLC-HRMS, we identified 43 potential migrants in PEEK pellets/film and 21 in TPU pellets/SPEEK-TPU blend film. Comparative analysis reveals that the finished films contain a substantially broader and more diverse set of NIAS than the raw materials, including ethoxylated oligomers, caprolactam oligomers, and quaternary ammonium degradation products that are not detected in the raw materials. Migration experiments confirm the release of 4 compounds from PEEK film and 6 from the blend film into food simulants. A risk-ranking model applied to methanol extracts serves as a hazard-based prioritization tool, whereas the threshold of toxicological concern (TTC) comparison is based on actual migration. Notably, tetrabutylammonium from the blend film shows a semi-quantified exposure that exceeds the TTC by 1.85-fold under acidic conditions in the migration test, flagging it as a priority compound for further confirmatory analysis. A risk-ranking model further classifies five substances as Risk I (e.g., sulfonated surfactants, benzophenone derivatives). Our findings demonstrate that NIAS originating from finished films contribute substantially to the migration risk profile of advanced FCMs, providing a pragmatic framework for next-generation food packaging safety evaluation.