Indigenized Characterization\nFactors for Health Damage\nDue to Ambient PM<sub>2.5</sub> in Life Cycle Impact Assessment in\nChina

Life cycle assessment (LCA) is a broadly used method\nfor quantifying\nenvironmental impacts, and life cycle impact assessment (LCIA) is\nan important step as well as a major source of uncertainties in LCA.\nCharacterization factors (CFs) are pivotal elements in LCIA models.\nIn China, the health loss due to ambient PM<sub>2.5</sub> is an important\naspect of LCIA results, which, however, is generally assessed by adopting\nCFs developed by global models and there remains a need to integrate\nlocalized considerations and the latest information for more precise\napplications in China. In this study, we developed indigenized CFs\nfor LCIA of health damage due to ambient PM<sub>2.5</sub> in China\nby coupling the atmospheric chemical transport model GEOS-Chem, exposure–response\nmodel GEMM containing Chinese cohort studies, and the latest local\ndata. Results show that CFs of four major PM<sub>2.5</sub> precursors\nall exhibit significant interregional variation and monthly differences\nin China. Our results were generally an order of magnitude higher\nand show disparate spatial distribution compared to CFs currently\nin use, suggesting that the health damage due to ambient PM<sub>2.5</sub> was underestimated in LCIA in China, and indigenized CFs need to\nbe adopted for more accurate results in LCIA and LCA studies.