From Legacy to Emerging Polycyclic Aromatic Compounds: Profiling in micro-nanoplastics emissions from plastic incineration

Polycyclic aromatic compounds (PACs) are organic pollutants associated with incomplete combustion processes and connected to severe health effects. Their connection to micro-nanoplastics (MNPs) emitted as particulate matter from incineration of plastics remains poorly explored. In this study, we detected 65 Polycyclic Aromatic Hydrocarbon (PAH), oxygenated (OPAH) and nitrated (NPAH) PAC species in MNPs emitted during the incineration of three widely used plastic materials, high-density polyethylene (HDPE), polypropylene (PP) and polyvinyl chloride (PVC). MNPs were generated using the incineration exposure generation system (INEXS) and their PAC profile was offline analyzed using gas chromatography-mass spectrometry. Notably, one of the most abundant species in all three plastics was Benzanthrone, an OPAH previously associated with traffic and biomass burning emissions. MNPs emitted by PVC incineration contained emerging highly toxic PAC species such as benzo(c)fluorene, dibenzopyrenes, and 6-nitrochrysene. Our findings highlight the importance of monitoring beyond the legacy 16 EPA members which accounted only by 12%, 47%, and 41% of the associated carcinogenic potency (expressed as BaPeq), for PVC, PP and HDPE respectively. These results raise concerns for potential health implications and underscore the urgent need for further research on this new environmental challenge, MNP pollution and its association with toxic persistent pollutants.