Occurrence and prioritization of non-volatile substances in recycled PET flakes produced in China

• Published in: Chemosphere (Oxford) 2024-03, Vol.352, p.141508-141508, Article 141508
• Main Authors: Wu, Xuefeng, Su, Qi-zhi, Yue, Xin, Li, Hanke, Yang, Jinghua, Wu, Siliang, Zhong, Huai-Ning, Li, Dan, Jianguo, Zheng, Chen, Sheng, Dong, Ben
• Format: Article
• Language: English
• Subjects: China; Dibutyl Phthalate - analysis; Food contact application; Food Contamination - analysis; Genotoxicity screening; Hot-washed flakes; Humans; Non-volatile substances; Positron-Emission Tomography; Prioritization; Recycled plastics; Recycling
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2024.141508

Recycled PET (rPET) is gaining popularity for use in the production of new food contact materials (FCMs) under the context of circular economy. However, the limited information on contaminants in rPET from China and concerns about their potential risk are major obstacles to their use in FCM in China. Fifty-five non-volatile compounds were tentatively identified in 126 batches of hot-washed rPET flakes aimed for food packaging applications in China. Although the 55 substances are not necessarily migratable and may not end up in the contacting media, their presence indicates a need for proper management and control across the value chain. For this reason, the 55 substances prioritized on the basis of level of concerns and in-silico genotoxicity profiler. Among them, dimethoxyethyl phthalate, dibutyl phthalate, bis(2-ethylhexyl) phthalate were classified as level V substances, and Michler's ketone and 4-nitrophenol were both categorized as level V substances and had the genotoxic structure alert, while 2,4,5-trimethylaniline was specified with genotoxic structure alert. The above substances have high priority and may pose a potential risk to human health, therefore special attention should be paid to their migration from rPET. Aside from providing valuable information on non-volatile contaminants present in hot-washed rPET flakes coming from China, this article proposed a prioritization workflow that can be of great help to identify priority substances deserving special attention across the value chain. [Display omitted] •Limited information and potential risk in rPET are major obstacles their use as FCM in China.•A survey on non-volatile contamination of rPET in China was conducted.•Six compounds categorized as level V or with alert structure deserved further attention.•Prioritization workflow to identify priority substances deserving attention was proposed.