Navigating regulatory complexities: Challenges and shifting problem framings in turning microplastics into a European policy object

Abstract Microplastics are widely discussed as a pervasive environmental issue, yet decisive action and turning them into a governable “policy object” has proven to be slow and challenging. This paper investigates the shifting and heterogeneous problem framings of microplastic pollution and the regulatory complexities that emerge from them. Drawing on research from science and technology studies, we analyze how microplastics remained “hidden in plain sight” for decades, obscured by limited scientific standardization, competing problematizations, debates over scientific evidence, widespread cultural imaginaries and economic interests. The research reveals that the path from scientific knowledge to policy action is not linear but a process of co-production, where public concern, scientific capabilities and political agendas continuously reshape one another. We trace the evolution of the issue – from marine pollution to other media, human health and now nanoplastics – highlighting how each shift opens up new questions posing new (regulatory) challenges. The findings demonstrate that effective environmental governance requires more than data; it demands a critical understanding of the complex innovation pathways that produce such residues. We conclude that durable solutions require extended infrastructures of responsibility and care and the development of adaptive institutional frameworks capable of navigating scientific uncertainty and contested values.