Circular Economy and Cradle to Cradle Design have been gaining significant attention in minimising the life cycle environmental footprint of a product or service. However, it remains challenging to model multiple cycles where the products could be finitely or infinitely recovered through upcycling or downcycling, depending on the quality changes, and used as a material in the different product life cycles. This study aims to summarise the Life Cycle Assessment (LCA) methods that consider the cascade utilisation and upcycling of a product which will also apply to the case of plastic recycling. The methodological challenges, particularly for secondary and tertiary plastic recycling, are highlighted. The mini-review is intended to identify the limitation of current assessment methods for the subsequent development of an improved LCA in future work.
