Hadi Rezvani* and Mihir Kapadia* and Julia Costantino* and Navid Zarrabi* and Sajad Saeedi** and Nariman Yousefi*

*Toronto Metropolitan University (TMU)

**University College London (UCL)

This study presents a comprehensive and comparative analysis of the emergence of micro- and nanoplastics (MNPs) from polyethylene (PE) plastic bags and polyethylene terephthalate (PET) water bottles. We subjected these polymers to simulated mechanical and photodegradation conditions in an isolated chamber for 12 weeks to understand their environmental implications and degradation mechanisms. We analyzed 614 and 3,924 plastic particles that emerged from PE and PET, respectively, using an artificial intelligence (AI) enhanced automatic annotation tool (FastSAM) focusing on MNP’s particle count, size distribution, and morphology. This innovative approach combines comprehensive simulation of environmental conditions with AI-enabled image analysis, providing detailed insight into the relative contributions of PE and PET products to plastic pollution. Our findings indicate that PET fragments more readily into smaller particles, with a higher proportion of nanoplastics (57.6%) than PE (24.9%). The concentration of the emerged particles was found to be 4.17 million particles/L (0.07 ppm) for PE and 27.8 million particles/L (0.18 ppm) for PET. Characterization techniques, including dynamic light scattering (DLS), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) were used to examine both bulk plastics and the MNPs that emerged from them.