Mechanical performance-based environmental labelling of asphalt mixtures: a state-of-the-art review

Objectives The environmental impact of asphalt mixtures has gained attention in the search for sustainable road infrastructures. However, the lack of standardised methodologies for environmental assessment and labelling hinders material selection from this perspective. This study presents a state-of-the-art review on environmental labelling of asphalt mixtures.Methods A total of 127 studies were analysed, covering methodologies such as Life Cycle Assessment, Environmental Product Declarations, single impact indicators, benchmarking, and sustainability indices or labels, whose logic may inspire future labelling systems. The review also evaluates whether these approaches integrate mechanical performance into environmental analysis.Findings The results indicate substantial methodological diversity across the reviewed approaches, reflecting their distinct objectives and decision contexts. While most studies rely on cradle-to-gate LCAs, which limits the representation of long-term durability and functional performance, several methodologies already incorporate complementary logics, such as benchmarking, multi-criteria decision-making, or performance screening, that can support environmental comparison and classification. Approaches that integrate environmental assessment with mechanical indicators or pavement performance modelling emerge as particularly promising, although still limited by data availability and methodological complexity.Novelty Overall, the findings suggest that harmonised yet flexible frameworks, capable of combining environmental metrics with criteria based on simulated mechanical performance, are essential for advancing environmental labelling of asphalt mixtures.