Table provides an overview of all samples used. We procured the commercial samples PPneedles c , PET-spheres c , and PE-spheres c from Nanochemazone (Leduc, AB, Canada) and PPspheres c from Goonvean Fibers (Cullompton, UK). In addition to commercially sourced samples, we generated samples by the breakdown of each polymer type in the laboratory: PP-fibers b originating from a PP rope (The Home Depot, Everbilt Light-Duty Diamond Braid Rope, Model # 301831), PE-flakes b from a PE cup (The Home Depot, LESSO Test Cap 3, Model # RLN132-030), and PET-fibers b originating from PET textile. To obtain PP-fibers b and PE-flakes b , we first cut the rope and the cup into small pieces (approximately 1 cm long), then dipped them into liquid nitrogen, broke them apart using a mortar and pestle, and then passed the material through a filter sieve. PET-fibers b were made by Cotton Incorporated (North Carolina, USA), which produces standard fiber textiles for environmental assessments and toxicity studies. We cut the PET fabric into small pieces of approximately 1 cm 2 and then ground them using a Wiley Mill 134.