Cradle-to-gate life cycle assessment of cosmetic-grade hyaluronic acid in China via microbial fermentation: hotspots and mitigation levers

Cosmetic-grade hyaluronic acid (HA) has rapidly expanded in global markets, yet its environmental profile in China—the largest producer worldwide—remains unclear. This study aims to establish a transparent cradle-to-gate life cycle assessment (LCA) for HA produced via microbial fermentation, identify environmental hotspots, and propose targeted mitigation measures.

Following ISO 14,040/44 standards, the cradle-to-gate impacts of producing 1 kg freeze-dried HA in mainland China (2022) were quantified using plant-specific data combined with Chinese Life Cycle Database (CLCD) 0.9 and Ecoinvent 3.10 background datasets. Nine midpoint impact categories were evaluated (e.g., global warming potential, fossil resource depletion, water use). Sensitivity analysis and scenario modeling explored the influence of utility sources, solvent recovery, and wastewater methane control.

The baseline carbon footprint (GWP) was 180.28 kg CO₂-eq per kg HA, with fossil energy use (1356.22 MJ) and water consumption (105.89 m³) also substantial. Utilities and core production dominated carbon footprint (GWP ≈ 60%), fossil resource use (ADP-fossil) (~ 51%), and water use (WU) (~ 55%), while fermentation contributed most to eutrophication and mineral depletion (> 70%) and purification drove ozone-depletion potential (ODP) (~ 44%). Wastewater treatment added a secondary hotspot via methane emissions (~ 19% of GWP). Scenario tests showed that 100% renewable electricity and 95% ethanol-recovery loops achieved the largest improvements across multiple indicators with minimal trade-offs.

This study provides the first benchmark LCA for cosmetic-grade HA in China, highlighting utilities, fermentation media, purification solvents, and wastewater methane as priority intervention points. Effective mitigation strategies include utility decarbonization with heat integration, methane capture and oxidation, media optimisation, solvent-loop closure, and water recirculation. These findings support suppliers, cosmetics brands, and policymakers in reducing the environmental footprint of HA while aligning with carbon-neutrality targets and eco-label requirements.