Stability and dispersibility of microplastics in experimental exposure medium and detection of nanoplastic fractions by SMLS, SAXS, Raman microscopy, and SEM

The accumulation of non-biodegradable microplastics in the environment and the contamination of food and drinking water pose a significant risk to ecosystems and human health. The physical and dimensional characterizations of microplastics suspensions are essential to implement regulations with the aim of monitoring microplastics pollution and limiting human exposure. The knowledge about the fate of particles including the detection of nanoplastics is still limited. To fill this gap, we investigated the dimensional characterization of microplastics in situ and we analyzed the impact of the protein corona, which forms in biological media, on the size measurement of micro/nanoplastics in suspension. Using static multiple light scattering (SMLS), small angle X-ray scattering (SAXS), Raman microscopy, and scanning electron microscopy (SEM), we defined the size distribution, density, stability, and agglomeration state of polyethylene and polypropylene MPs in complex media. Our analysis demonstrates the detectability of secondary nanoplastics, paving the way for monitoring and controlling human exposure. The identification of nanoplastics debris released during exposure time of MPs in BSA media without mechanical stress highlights the role of biotic processes in microplastics fragmentation. Debris released in the suspension could be described as small and irregular fragments and cracked particles. Also see: https://micro2024.sciencesconf.org/554002/document