Characterization of nanoplastics and microplastics in environmental matrices by thermal and separative methods

We can easily qualify plastic as one of the most used materials in the world. The mass released into the environment leads to the production of particles of random size and shape called microplastics (MPs) and nanoplastics (NPs). The main risks associated to the formation of these particles are: (i) the release of additives, (ii) the ability to transport and concentrate others contaminants such as metals, pesticides or volatile organic compounds (VOCs). This lead effect, also known as the 'Trojan horse effect', results in the bioaccumulation of pollutants and their transfer throughout the food chain. To date, the information on their presence and behavior in the environment remains poorly or not documented: this is due to the lack of methods capable of detecting them. In this context, the objective of the thesis was to characterize NPs and PMs by thermal and separative methods. Py-GCMS is one of the most interesting analytical technique to identify polymers. However, in an environmental sample, the organic matter (OM) masks this potentiality, even more so for nanoscale PS. Therefore, we proposed a comprehensive study of the possibility to detect and quantify Ps NPs in a rich phase containing OM. In contrast to NPs, there are currently many methods to characterize MPs in environmental samples. However, none of them are able to assess the sources and processes of MPs in the environment. Therefore, we present the development of an original purge and trap-GC-MS-C-IRMS system to explore the analysis of stable carbon isotopes specific to VOCs extracted from MPs. This study presents the development of the method using a commercial PS MPs according to temperature, and mass. Then, an exploratory analysis of the method optimized on other types of MPs (polyethylene, polylactic acid). (author)