Clarifying the Taxonomy of Plastics and Bioplastics: Toward a ‘Zero-Trace Plastic’ (ZTP) Material Framework

The lack of precise definitions in plastics-related terminology continues to hinder the development of coherent sustainability strategies across the materials value chain. This communication revisits current definitions of plastics, polymers, and bioplastics, distinguishing between source (bio-based vs. fossil-based), structure (synthetic vs. natural polymer), and degradation behaviour (persistent vs. compostable or biodegradable). It critiques ambiguous classifications promoted in policy and marketing discourse. It introduces the concept of “Zero-Trace Plastic” (ZTP) to refer to materials that are non-plastic substitutes intended for versatile plastic-like uses while guaranteeing no trace of synthetic plastics in their composition and no contribution to pollution across their lifecycle. The ZTPframework prioritises complete mineralisation without plastic or microplastics or chemical residues under real-world conditions. ZTP is proposed not as a replacement for existing biodegradability standards, but it helps distinguish between plastic and non-plastic biopolymers and works as a complementary benchmark for biodegradability that aligns with and extends them by incorporating environmental specificity and system-wide traceability. The paper proposes a harmonised terminology matrix and calls for coordinated efforts by international agencies and standardisation institutes, national bodies and industries to avoid using misleading terminologies like bioplastics, often used for greenwashing and to enhance circular material strategies.