Insights into the Potential Effects of Micro(nano)plastic-Containing Nanoparticles in the Environment

Micro(nano)plastics (MNPs) can be generated from a variety of sources, including the breakdown of larger plastic items, the abrasion of synthetic textiles, and the fragmentation of plastic waste. These particles can become airborne and be transported by wind, potentially leading to their presence in the atmosphere. Due to their widespread applications, ZnO particles at the nanometer range have attractive proprieties that make them appropriate for being combined with polymers, especially PET (polyethylene terephthalate), the most commonly used polymer in the packaging sector. Nevertheless, ZnO NPs have a potential ecotoxicity that could be reflected in PET-ZnO composites reaching the environment in the form of micro(nano)plastics. To assess the potential release of PET-ZnO, as well as the ecotoxicity of ZnO NPs, PET-ZnO and weathered composites were analyzed. The ecotoxicity of PET-ZnO was tested in organisms representing different food-chain levels and compared to ZnO NPs’ ecotoxicity. The composite form contained a stable dispersion of around 3.7% of NPs uniformly scattered in the polymeric matrix. ZnO NPs were toxic to Vibrio fischeri and Brachionus calyciflorus . PET-ZnO did not exhibited any toxicity to the organisms studied, while a moderate level of toxicity was observed for the weathered forms.