# Life Cycle Assessment (LCA) Methodology Life Cycle Assessment (LCA) quantifies the environmental impact of a product across its entire life — from raw material extraction through production, use, and end-of-life disposal. The governing standards are ISO 14040 (principles and framework) and ISO 14044 (requirements and guidelines). ## The Four Phases ### 1. Goal and Scope Definition Defines the purpose of the assessment, the intended audience, the system boundary, and the functional unit. The **functional unit** is the most important decision in an LCA. It sets the basis for all comparisons. A packaging LCA might use: *"1 kg of fresh strawberries preserved for 14 days at 4°C with less than 5% spoilage."* This enables a fair comparison between a conventional plastic tray and a bio-based alternative — normalised to the same delivered function, not just the same mass of material. System boundaries determine what is included: - **Cradle-to-gate:** raw material extraction to factory gate (common for ingredient suppliers) - **Cradle-to-grave:** full life including use phase and disposal - **Cradle-to-cradle:** includes recycling or composting loop ### 2. Life Cycle Inventory (LCI) Collects data on all material and energy inputs and outputs (emissions, waste) for each process in the system. Data sources include primary measurement, supplier declarations, and background databases (ecoinvent, GaBi, US LCI Database). ### 3. Life Cycle Impact Assessment (LCIA) Translates inventory flows into impact categories using characterisation factors. Key impact categories: | Category | Unit | Key Driver | |---|---|---| | Global warming potential (GWP) | kg CO₂ eq. | Energy source, land use change | | Ozone depletion | kg CFC-11 eq. | Halogenated compounds | | Eutrophication | kg PO₄ eq. | Nitrogen and phosphorus releases | | Acidification | kg SO₂ eq. | Sulphur and nitrogen oxides | | Land use | m² × year | Agricultural feedstock area | | Water scarcity | m³ water eq. | Regional water stress weighting | Common LCIA methods: ReCiPe, CML, TRACI (North America), EF (EU Environmental Footprint). ### 4. Interpretation Identifies hotspots, evaluates uncertainty, and draws conclusions relevant to the stated goal. A sensitivity analysis tests how much the result changes when key assumptions vary. ## The Challenge for Natural Antimicrobials Agricultural feedstocks introduce high variability into LCA results: - Farming method (conventional vs organic vs regenerative) changes pesticide, fertiliser, and energy inputs substantially - Geography and climate determine irrigation demand and background electricity grid mix - Seasonal variation means a single annual average may mask peak impact periods Background database coverage for agricultural byproducts (pomace, peels, shells) is inconsistent. Allocation decisions — how to divide impact between a main crop and its by-product — significantly affect results and are contested in the literature. ## LCA as Commercial Infrastructure An LCA-backed environmental claim is defensible in front of procurement teams, ESG due diligence processes, and regulators. A number without an LCA is just a marketing assertion. For packaging materials, EU Green Claims Directive (proposed) will require substantiated, independently verified environmental claims. Companies without LCA data will not be able to make comparative environmental statements. LCA data feeds directly into EPR fee calculations under eco-modulation schemes — see: [[Extended Producer Responsibility]]. --- *Part of [[Natural Antimicrobials & Sustainable Materials MOC]]*