High-throughput toxicological profiling and ToxPi-based prioritization of chemical migrants from recycled paper used in food contact materials.

The circular economy has driven the development of recycled food contact materials (rFCMs). However, rFCMs may contain harmful intentionally added (IAS) and non-intentionally added substances (NIAS). This study evaluated the toxicity of rFCMs to facilitate their safe application in food packaging. A high-throughput in vitro toxicity screening technique was employed to examine paper and paperboard rFCMs following migration test with 3 food types and 4 simulants. Through Neutral Red uptake (NRU) and high-content screening (HCS) assays using HepaRG and HK-2 cell lines, we found that in 20% ethanol and 4% acetic acid migrants o rFCMs may disrupt cellular and targeting mitochondrial homeostasis. In real food, paper rFCMs appear suitable for non-fatty and dry foods, indicating they can be safely utilized as FCMs within these categories. Metals, di(2-ethylhexyl) phthalate (DEHP), and tris(2-butoxyethyl) phosphate (TBOEP) showed the significant correlations with cellular toxicity. ToxPi prioritization, integrating chemical analysis and HCS-based cytotoxicity assessments, highlights the necessity for further research and priority attention on paper rFCMs in direct contact with fatty foods, alcohol, and acidic foods. This study provides valuable insights for manufacturers and policy makers in regulating paper and paperboard rFCMs, ensuring food safety and consumer health.