Valorising waste in biomanufacturing: Complexities of circularity, safety and sustainability

A global systematic change of how we produce and manage resources is essential to ensure societal well-being and restore natural ecosystems. While concepts such as closed-loop systems, Life-Cycle-Thinking (LCT) and circular design have been at the forefront of international discourse for decades, researchers and developers often struggle addressing, communicating and engaging holistically with the relevant topics and stakeholders. This hesitancy limits the critical assessment of their contributions to circularity, safety and sustainability, and ultimately their impact. This paper comprehensively explores the complexities of integrating circularity into novel biomanufacturing research that valorises waste- and side streams. We propose addressing these intricacies by making frameworks like Safe-and-Sustainable-by-Design (SSbD) and LCT more accessible to early-career researchers who work on circular (bio)economy topics, which increasingly require transdisciplinary collaboration and approaches to thrive. Here, we use a combinatorial approach to shed light on this topic, undergoing a desk study, semi-structured expert interviews, and integrating a hands-on experimental project to our learnings, where we applied the SSbD concept to early experimental decision-making and for critical reflection. Moreover, we present an overview of concept levels that should be assessed to understand the impact of a production process, highlight key EU regulatory frameworks, and showcase relevant literature for a structured approach for more sustainable development in manufacturing. Our findings emphasise the lack of a clear waste definition and management consensus, unfair competition with the highly optimised, subsidised, fossil-based industries, misaligned regulation to facilitate international resource management and infrastructure, and the absence of standardised, holistic cost-environmental-social impact assessments. • Circular economy networks need trained developers to navigate systemic challenges. • While also technical, waste valorisation limits are mainly regulatory and managerial. • In manufacturing, safety is stringently addressed but sustainability is lagging. • Stronger sustainability incentives and enforcement are needed for true circularity. • Early cross-sectoral- and Life-Cycle-Thinking are key for sustainable innovation.