Jules Bellon, Feriel Bacoup, Aamir Shehzad, Richard Gattin
Biodegradable plastics offer a promising alternative to conventional plastics, but their environmental benefits depend heavily on appropriate end-of-life strategies. Home composting stands out as a decentralized and accessible option with low infrastructure needs and strong potential to involve citizens in sustainable waste management. However, its effectiveness remains uncertain due to fluctuating conditions—such as temperature and humidity—arising from the small scale of composting systems, variability in household practices, and geographic or seasonal influences. These constraints pose significant challenges for the reliable home compostability of bioplastics. This comprehensive review examines the characteristics of decentralized composting systems and their influence on the biodegradation of biodegradable plastics. A total of 48 experimental studies were analysed: 27 conducted under controlled laboratory conditions and 21 under real-life or uncontrolled environments. These studies assessed biodegradability using respirometric techniques, weight loss measurements, or both. Three major factors were identified as key drivers of biodegradation rates: (i) the composition of the plastic, including polymer type, chemical structure, and the presence of fillers or additives; (ii) composting system parameters, such as aeration, volume, and temperature stability; and (iii) the properties of the composting medium, including microbial community composition and nutrient availability. In addition, the review discusses the risk of microplastic persistence, and the methodological heterogeneity observed across studies, which complicates the assessment and comparison of results. Practical recommendations to enhance home composting performance are provided throughout the paper, supporting the development of robust, context-sensitive home-compostability assessment frameworks.