Assessing Mineral and Metal Resources in Life Cycle Assessment: An Overview of Existing Impact Assessment Methods

Mineral resources and metals are integral to modern society, with growing demand driven by recent technological advancements. Life cycle assessment (LCA) provides a valuable framework for assessing resource use, and numerous methodologies have been developed to address both the midpoint and endpoint levels of life cycle impact assessment (LCIA). This review aims to provide a comprehensive overview of the existing LCIA methodologies related to minerals and metals, with a focus on recent developments, progress made, and potential future directions. It examines these LCIA methods in terms of resources considered, underlying assumptions, data sources, and identified limitations. According to the nature of the underlying considerations, the various methods are grouped into different families. In addition, the novelty of this article is to place raw material criticality considerations alongside LCA characterization methods; however, only one class of critical raw materials, rare earth elements (REEs), is considered. These REEs are mainly used in electrical and electronic components (e.g., electric vehicle motors) and in various renewable energy technologies (e.g., wind turbines) due to their unique properties that make them difficult to substitute. However, their supply is constrained by limited global reserves and their concentration in a few countries. This situation highlights the need for more reliable and accurate data on resource production and recycling. Additionally, this review presents case studies that apply LCIA methods to real-world scenarios, illustrating current capabilities as well as areas where further research and refinement are needed.