Nanoplastic Release from Disposable Plastics: Correlation with Maximum Service Temperature

Abstract

The potential for bioaccumulation of nanoplastics (NPs, <1 µm) increases as the particle size decreases. Since several disposable plastic products used daily may release NPs, their intake may be unavoidable. Therefore, it is crucial to examine the release patterns of NPs from these products. This study investigates the relationship between NP release and the Maximum Service Temperature (MST) of five plastic types, confirming the correlation under real-world conditions. The releasing tendencies of NPs were investigated using plastic pellets. We simulated the packaging of hot food in plastic containers, considering the physical dynamics of food delivery, and replicated cooking in an oven and microwave. We observed that the mass of NPs released tended to reach its maximum at the material's MST. In real-life conditions, the release of NP was found to increase with higher container content temperatures and longer packaging or cooking durations. Physical impacts were confirmed to be the most significant contributors to NP release. Moreover, Higher microwave power levels lead to greater NP release, with polar materials releasing more NPs compared to non-polar materials. Consequently, to minimize NP ingestion, it is recommended to use containers made from non-polar materials with a high MST.