Author(s): Jiwon Son; Soobin Yang; Yejin Nam; Hansang Lee; Changwoo Kim
Linked Author(s): Changwoo Kim
Keywords: Nanoplastics single-use plastics maximum service temperature reusable products coating thickness
Abstract: The increasing use of single-use plastic and paper-based products offers convenience but raises significant concerns about the release of nanoplastics (NPs) and their potential risks to human health and the environment. This study systematically analyzed the NP release characteristics from various plastic materials (PS, HDPE, PP, PET, NY6) and paper-based containers coated with low-density polyethylene (LDPE) and polylactic acid (PLA). The influence of realistic usage conditions such as temperature, physical agitation, cooking time, and microwave power was evaluated to understand their impact on NP release. In experiments with plastic products, NP release peaked within the maximum service temperature (MST) range and increased significantly with higher temperatures and prolonged cooking times. Non-polar materials (PS, HDPE, PP) exhibited particle aggregation at lower temperatures, while polar materials (PET, NY6) showed higher NP release due to particle fragmentation at elevated temperatures. Particularly under microwave and oven conditions, PET and NY6 released substantial amounts of NPs due to thermal vibration of polar molecules. For paper-based containers, LDPE-coated cups released up to 26 times more NPs than PLA-coated cups, especially at temperatures above 80°C and under increased physical agitation. In microwavable containers, PLA coatings released up to 40,000 times more NPs than LDPE coatings, with higher microwave power (1000W) and extended exposure (10 minutes) being key contributing factors. LDPE coatings, due to their non-polar characteristics, exhibited lower NP release, while PLA coatings were more prone to NP release under microwave conditions due to molecular vibrations at 2.45 GHz. Increasing coating thickness significantly reduced NP release, with negligible release observed for coatings thicker than 1 mm. This study highlights the relationship between MST and NP release, offering insights into selecting materials and optimizing coating thickness to minimize NP release. It emphasizes the adoption of reusable products and the use of non-polar materials with higher MSTs as effective strategies to mitigate environmental and health risks.
Year: 2025