From Expanded Polystyrene to Circularity: A Systematic Literature Review of Passive Cold Chain Packaging Through the 10-R Framework in the Era of the EU Packaging and Packaging Waste Regulation

The cold chain sector is responsible for approximately 4% of global GHG–greenhouse gas emissions. Its passive thermal packaging, which has historically been dominated by expanded polystyrene (EPS), is both a crucial functional component and a significant environmental liability. Regulation (EU) 2025/40 on packaging and packaging waste (PPWR), along with the Single-Use Plastics Directive, the Ecodesign for Sustainable Products Regulation, and the Digital Product Passport, creates cumulative regulatory pressure on EPS and opens the market to alternative passive solutions. This systematic literature review, conducted according to the PRISMA 2020 protocol, addresses three research questions regarding the maturity of EPS alternatives such as phase change materials, vacuum insulated panels, mycelium composites, moulded pulp, dry-moulded fibre, and reusable pooled systems. It examines the cumulative effects of the EU regulatory framework and the systemic interventions needed for a circular transition, interpreted through the ten-R hierarchy. The review introduces the Cold Chain Packaging Circular Transition Framework (CCP-CTF), which is articulated across four dimensions and implemented as a composite indicator across five transition regimes, in addition to a residual EPS scenario. This framework is visualised as a Cold Chain Sustainability Thermometer—a calibrated assessment tool for researchers, policymakers, and industry operators navigating the 2026–2040 PPWR implementation timeline. The review identifies key knowledge gaps, including limited integration of decarbonisation accounting at the packaging-logistics interface, fragmentation of Extended Producer Responsibility schemes in the pharmaceutical sector, and the lack of harmonised eco-modulation criteria for cold chain packaging at the European Union level.