Integrating circular economy, cradle-to-cradle, and closed loop systems in fashion supply chains: a systematic review from an industrial ecology perspective

The fashion industry, a leading contributor to carbon emissions, faces sustainability challenges despite extensive adoption of circular economy (CE) principles in the literature. While cradle-to-cradle (C2C) and closed-loop systems (CLS) are also corresponding pillars for sustainability, their integration with CE to reflect their systematic impact remains underexplored. This study extracted 110 peer-reviewed studies to examine how CE, C2C, and CLS are applied across fashion supply chains. Moving beyond descriptive mapping, this study integrates an industrial ecological framework with technological readiness level (TRL) to assess where and why circular interventions succeed or face barriers across the product lifecycle. The findings show that current policy environments fail to connect early-stage CE concepts at TRL 1–4, with the technical realities of material and operational closure in C2C and CLS at TRL 4–6. The misalignment, compounded by regulatory inertia, inhibits progression towards large-scale applications. This study directly addresses a critical mid-TRL bottleneck caused by regulatory and infrastructure inertia, along with fragmented implementation across the supply chain actors. By mapping circular strategies to TRLs and lifecycle stages, this study provides actionable pathways for policymakers and industry stakeholders to accelerate system-level, scalable circular transitions in the fashion sector.