Environmental Analysis of Emulsified Asphalt Products in the United States: A Comparative Cradle-to-Gate Life Cycle Assessment

Growing interest in reducing the environmental impacts of pavement preservation materials has increased the need for evaluations of emulsified asphalt. This study applies a cradle-to-gate Life Cycle Assessment (LCA) to quantify and compare the environmental profiles of four widely used cationic emulsions in the United States: CSS 1, CSS 1H, CRS 2, and CRS 2P. The assessment incorporates primary data collected from 17 manufacturing plants across different regions, supported by information from suppliers and secondary datasets from the 2023 GaBi database. Impact calculations were performed using GaBi software, and sensitivity analyses were conducted to determine which formulation components most influence the results. Environmental impact categories in the study include global warming potential (GWP), particulate matter (PM 2.5 ), photochemical ozone creation potential (POCP), and renewable and nonrenewable primary energy demand. The findings show that rapid-setting emulsions (CRS 2 and CRS 2P) generally exhibit lower environmental burdens than slow-setting emulsions (CSS 1 and CSS 1H). Differences in asphalt binder content, emulsifier dosage, and latex additions were identified as major contributors to environmental performance. By identifying key drivers of environmental impact, this study supports more sustainable material choices in pavement preservation. The results provide updated industry-specific LCA benchmarks for emulsified asphalt and highlight opportunities for environmental improvement through targeted adjustments to product formulations.