Environmental performance of analytical methods: insights from life cycle assessment on four analytical chemistry workflows

Analytical chemistry plays a central role in research and innovation, yet its environmental impacts remain insufficiently represented in sustainability assessments. Current score-based "greenness" indicators-defined as the compliance to the 12 green analytical chemistry principles-often overlook upstream and downstream processes, such as instrument manufacturing and data management. This study applies life cycle assessment (LCA) to characterize the environmental performance of four representative workflows in a cosmetic industry R&I setting: an untargeted UPLC-PDA/HRMS analysis of natural extracts and three phenoxyethanol quantification methods (GC-MS, HPLC-UV, UPLC-UV). Inventories were structured to distinguish sample preparation, instrumental analysis, and data processing from supporting flows like consumables and energy. The results reveal distinct environmental hotspots for each protocol. The UPLC-PDA/HRMS workflow exhibited a climate change impact of 4.30 kg CO₂eq, driven by the amortization of the devices and the sample transport. In contrast, the GC-MS workflow (3.82 kg CO₂eq) was heavily influenced by dichloromethane production, while the HPLC-UV protocol reached 6.84 kg CO₂eq due to consumable-related flows and longer run times. These findings demonstrate that environmental burdens are highly workflow-specific and that commonly cited factors, such as solvent use, are not always the primary drivers. The study concludes that the normalization factors from the product environmental footprint (PEF) method are inadequate for analytical laboratory contexts and suggests that quantitative LCA provides a necessary complement to score-based metrics like the analytical greenness metric (AGREE) for supporting robust eco-design and corporate sustainability initiatives.