Migration of (non-) intentionally added substances and microplastics from microwavable plastic food containers

Microwavable plastic food containers (MPFCs) are extensively used for food storage, cooking, rapid heating and as take-out containers. There is an urgent need to investigate whether MPFCs pose potential health risks, as a result of the migration of chemicals into foods. Herein, 42 intentionally added substances (IAS) and > 100 non-IAS (NIAS) migrating from MPFCs were identified in food simulants according to Regulation (EU). The migration of major IAS and NIAS was higher in 95% ethanol compared to other simulants, and gradually decreased following repeated use. NIAS, including Cramer class III toxic compounds, such as PEG oligomers of N,N-bis(2-hydroxyethyl) alkyl(C8-C18)amines, isomers of hexadecanamide and oleamide, and Irgafos 168 OXO were detected and exceeded the recommended limits in some MPFCs. Furthermore, microplastics (MPs) were detected with high values of over one million particles/L in some MPFCs in a single test, and migration behaviors of MPs in different MPFCs were diverse. Surprisingly, this rigorous migration might result in an annual intake of IAS/NIAS up to 55.15 mg and 150 million MPs particles if take-out food was consumed once a day. Multi-safety evaluation studies on the migration of various chemicals from MPFCs to foodstuffs during food preparation should be assessed.