LCIA framework and cross-cutting issues guidance within the UNEP-SETAC Life Cycle Initiative

Area of Science:

• Environmental Science
• Life Cycle Assessment
• Sustainability Science

Background:

• Growing demand for decision support in LCA necessitates updated global guidance.
• Advancements in scientific knowledge require refinement of environmental life cycle impact assessment (LCIA) indicators.

Purpose of the Study:

• To present findings on LCIA cross-cutting issues and update the UNEP-SETAC LCIA emission-to-damage framework.
• To provide specific recommendations for human health (DALY) and ecosystem quality (PDF) metrics.
• To emphasize transparent reporting of LCIA models, reference states, and assumptions.

Main Methods:

• Task force analysis of LCIA cross-cutting issues including spatiotemporal aspects, reference states, normalization, weighting, and uncertainty.
• Review and update of the existing UNEP-SETAC LCIA emission-to-damage framework.
• Development of recommendations for specific impact metrics and reporting standards.

Main Results:

• Recommendations for Disability Adjusted Life Years (DALY) and Potentially Disappeared Fraction of species (PDF) metrics.
• Emphasis on transparent reporting to facilitate method comparison.
• Advocacy for spatially regionalized characterization models and standardized reporting formats for spatial data.

Conclusions:

• Transparent reporting of LCIA models, reference states, and assumptions is crucial for cross-comparison.
• Development of spatially regionalized models is recommended where applicable.
• Future efforts will focus on providing guidance for LCA practitioners and method developers on using and extending the UNEP-SETAC LCIA framework.