Environmental and ecotoxicity impacts of sunscreen formulations with a biobased SPF-booster: a life cycle assessment

Abstract

Purpose: The extensive use of chemicals across industries has raised environmental concerns, driving interest in enzymes as safer alternatives. While the ecological risks of certain traditional UV filters are well-documented, the overall environmental impact of complete sunscreens formulations remains underexplored. This study presents a life cycle assessment (LCA) comparing two sunscreen products: one with conventional UV filter and another incorporating an enzyme-derived polymer as a sun protection factor (SPF) booster. Methods: Employing a Life Cycle Assessment with a cradle-to-grave system boundary, the research evaluates the environmental impacts of the sunscreens with the EF3.1 impact assessment methodology. The study identifies key environmental impacts and hotspots across the product life cycle and assesses whether the enzyme-derived polymer reduces these impacts. The analysis also considers sunscreen emissions during the use stage modelling two scenarios, release into freshwater and release into marine environments. Results and discussion: The results show that raw material acquisition is the predominant contributor to environmental impacts in most categories. However, when the sunscreen is released into freshwater – whether directly or indirectly - the use phase becomes the most critical stage significantly contributing to ecotoxicity. A marked disparity in environmental impacts was observed between the two aquatic environments, with freshwater ecosystems experiencing much higher ecotoxicity than marine ecosystems. The enzyme-derived polymer led to modest reductions in ecotoxicity and human toxicity during the use stage; however, these improvements were largely offset by impacts occurring throughout the full life cycle. Conclusions: The study highlights the importance of evaluating the full sunscreen formulation – including all ingredients and life cycle stages - rather than focusing solely on UV filters as done in earlier assessments. It also emphasizes the urgent need for comprehensive data on chemical production processes and supports the integration of LCA with ecotoxicity testing as a pathway toward sustainable sunscreen design.