Résumé
With the compulsory separation of biowaste at source from January 2024 (in France and Europe), some compostable packaging could be processed in industrial composting plants in association with food waste. In line with the circular economy strategy, they could thus be transformed from waste into compost, a soil improver. In this context, an exhaustive experimental analysis of the transient and persistent degradation products generated by conventional and biodegradable plastics in this complex organic matrix is essential. Used as an organic soil improver in the agricultural sector, biowaste compost is a lignin-rich organic waste product that can be considered a potential source of microplastic soil contamination. To date, there is no standardized method for detecting and quantifying microplastics in compost. This study led to the development of an efficient, non-destructive preparation protocol for quantitatively extracting biodegradable and conventional nano and microplastics from compost. To identify and quantify the microplastics obtained, FTIR and Raman microspectroscopies were used alongside thermal analysis (Pyr-GC-MS). A critical comparison of these different methodologies is proposed.