Potential impact of abiotic resource use considering country-specific supply chain: consumption-based characterization and normalization utilizing a multi-regional input–output model

Abstract Purpose Life cycle impact assessment (LCIA) quantifies the potential impacts of environmental loads in the characterization step and evaluates their significance in the normalization step. This study develops consumption-based characterization factors (CFs) and normalization values (NVs) for abiotic resource use using a multi-regional input–output model. Consumption-based accounting in these steps is critical for ensuring consistency between the scope of these steps in LCIA and the overall evaluation scope of the life cycle assessment (LCA) study. Methods We calculated the consumption-based CFs and NVs for the target year 2015, covering 189 countries and regions for 29 mineral resources and three fossil fuels. These calculations were based on estimates of induced mine production and the adoption of country-level mine production-based CFs. The mining sector in the Eora multi-regional input–output database was disaggregated using country-level mine production data and trade statistics, enabling the estimation of induced mine production for each consuming country. A user cost model was adopted to calculate country-level mine production-based CFs. Results and discussion Consumption-based CFs varied significantly, with the maximum values being up to 3,300 times higher than the minimum, depending on the consuming countries. This highlights the importance of considering supply chain differences when assessing the potential impacts of abiotic resource use. The USA had the largest consumption-based NVs, followed by China and Brazil, with fossil fuels as the primary contributing resources. Some countries (e.g., Japan and Germany) exhibited notably higher consumption-based NVs compared to mine production-based NVs, reflecting their scarcity of primary resources in-country and underscoring the relevance of consumption-based NVs. Compared to previous studies with lower resolution for target resources, the consumption-based NVs developed in this study, which differentiate a greater variety of resources, offer more plausible results and enable more flexible analyses targeting specific resources. Conclusions Consumption-based accounting of the potential impacts associated with resource use can support LCA practitioners in conducting region-specific analyses without the need to identify mining countries for abiotic resources. The findings can also be utilized to analyze the responsibilities of consuming countries, sustainable supply chain management, and country-level supply risk assessments. Future work should focus on improving the disaggregation of metal-related sectors using smelter, refinery, and manufacturing data.