Evaluating the chemical safety of bio-based and biodegradable food packaging materials through non-targeted LC-HRMS analysis and in vitro bioassays

Bio-based and/or biodegradable polymers like all food-contact materials shall not transfer their constituents to food in quantities which could endanger human health. This work aims to evaluate the chemical safety of food contact bioplastics through an approach that combines a non-targeted liquid chromatography–high-resolution mass spectrometry (LC-HRMS) analysis emphasizing low-molecular weight oligomers and in vitro bioassays, including cytotoxicity assay, ROS production, inflammation tests, and in vitro assays to assess the endocrine activity. Seventeen samples including bio-polypropylene, bio-polyethylene, bio-polyester-based materials, bio-polyester-polyvinyl alcohol (PVOH), and polylactic acid (PLA)-based materials were assessed. A variety of different families of oligomers, specifically oligoesters, caprolactone oligomers, cyclic and linear oligomers of lactic acid (LA), and methoxylated and ethoxylated LA linear oligomers, were identified. Additives as well as their degradation products were also detected. An extract from each type of material was subjected to in vitro bioassays as part of hazard identification. The results showed that PLA, bio-polyester, and bio-polyester-PVOH showed the highest cytotoxicity, and bio-polypropylene and bio-polyethylene exhibited endocrine-disrupting potential. Furthermore, extracts from PLA have been shown to induce inflammation through high ROS production.