Scope 3 Chaos: Fixing the Math on Leather LCAs

Driving the news: Speaking last week at the APLF trade fair in Hong Kong, Dr. Greg Thoma introduced the Institute for Data Integrity (IDI)—a newly established, U.S. leather industry-funded 501(c)(3) non-profit organisation designed to serve as the definitive, open-source digital hub for standardized LCA data.

The big picture: Life Cycle Assessments (LCAs) are essential for measuring leather's environmental footprint, but fragmented data and wildly inconsistent methodologies are creating chaos for brands trying to report Scope 3 emissions (all indirect greenhouse gases occuring in a company's value chain). 

Why the IDI is urgently needed: Currently, the largest variable in a leather LCA is determining how much of the cattle's environmental burden belongs to the hide versus the meat.

• The mass vs. economic split: If allocated by mass, the hide carries roughly 4.8% of the animal's burden. If allocated by economic value (revenue fraction), it carries only 1% to 3.5%.
• The resulting chaos: This single methodological choice creates a massive factor-of-five difference in the final carbon footprint assigned to the leather. Without a standardized approach, brands receive a "mishmash" of conflicting data from different suppliers, severely undermining the credibility of the reporting.

Variables the IDI will harmonize:

Beyond standardizing allocation, the IDI platform will help the industry accurately account for other critical variables that current LCAs often misrepresent:

• Sourcing impacts: Dairy hides carry a significantly lower footprint because roughly 90% of the cow's lifetime emissions are allocated upstream to milk production. Conversely, grass-finished beef hides carry a higher carbon footprint than grain-fed hides, due to higher methane emissions from cattle digesting forage.
• The "functional unit" problem: Traditional LCAs frequently fail to account for leather's durability and longevity. The IDI aims to ensure material comparisons (e.g., leather vs. canvas shoes) are measured fairly over the number of years of service, rather than assuming a single, identical lifespan for both materials.

The IDI Solution & 2026 Roadmap:

To defragment this landscape, the IDI is actively building a tiered-access database to host science-based datasets and consensus methodologies.

• Unified data models: By establishing consistent, industry-wide product LCAs, every actor in the supply chain can pull from the exact same data models, which are being designed to link seamlessly with software like OpenLCA.
• Simplified collection: For tanneries, the IDI is developing a streamlined webform to make data collection smoother and less error-prone, focusing strictly on the metrics that actually matter.
• Scope 3 confidence: This cohesive approach ensures no double-counting or under-counting across the supply chain, finally giving brands the rigorous, standardized data they need for accurate Scope 3 reporting.

The Bottom Line: You cannot manage what you do not accurately measure. By operationalizing consensus methodologies and providing a transparent, centralized data platform, the IDI is stepping in to ensure the leather sector can accurately, consistently, and defensively communicate its true sustainability credentials to the modern market.

About Dr. Greg Thoma:

Dr. Greg Thoma is the Director of Agricultural Modeling and Lifecycle Assessment for the AgNext program at Colorado State University. In this role, he leads efforts in stakeholder-engaged, experimentally verified model development for sustainable animal agriculture systems. Prior to joining CSU, Dr. Thoma recently retired from a 28-year career in Chemical Engineering at the University of Arkansas, where he served as the inaugural Director for Research of The Sustainability Consortium. Having worked in sustainable food systems since 2008, he has led numerous agricultural life cycle assessment projects, serves as the North American subject editor for Agriculture for the International Journal of Lifecycle Assessment, and has been actively involved with the UN FAO's Livestock Environmental Assessment and Performance (LEAP) Partnership.

Dr. Greg Thoma on his Career, Modeling, and Interests

This podcast episode features Dr. Thoma discussing his extensive career background, his expertise in agricultural modeling, and his insights into life cycle assessments.