The social “grain of sand” in the circular economy. When users' deviant behaviors deplete waste collection workers and contaminate the material flows[Le « grain de sable » social de l’économie circulaire : Quand les comportements déviants des usagers épuisent les agents de collecte et contaminent les flux]

Research on the circular economy has primarily focused on the technical and industrial dimensions of recycling systems, while paying comparatively little attention to the social and organizational conditions under which material flows are produced. Yet, in the field of waste management, the effective implementation of circularity depends heavily on the coordination of stakeholders throughout the waste management process, particularly on citizens' waste sorting and presentation practices at the source. Waste collection therefore represents a critical component of the circular system, situated at the intersection of frontline waste workers' day-to-day activities and users' behaviours, but it remains largely overlooked in the literature. Drawing on a qualitative study based on 21 semi-structured interviews with waste collection workers, this paper examines how users' deviant behaviours affect both the day-to-day work of frontline waste workers and the overall performance of waste management flows. Using Conservation of Resources (COR) theory as an analytical framework, the findings show that sorting errors, lack of cooperation, inappropriate waste disposal, and uncivil behaviours constitute major sources of physical, emotional, and cognitive resource loss for workers. These resource losses compel waste collectors to compensate for upstream failures in the circular system through increased physical effort, heightened vigilance, and emotional investment, thereby contributing to work disruption and reducing the quality of the collected material streams. The study demonstrates that protecting the health and preserving the resources of waste collection workers are not merely social concerns but operational and technical prerequisites for the effective functioning of the circular economy. By shifting the analysis of circular performance upstream, towards source separation practices and the realities of waste collection work, this research shows that the circular economy cannot be properly assessed independently of the social conditions under which material flows are produced. These findings contribute to bringing the social dimension back into circular economy research, making waste collection work more visible, and reframing users' responsibility as co-producers of the public waste management service, thereby calling for a renewed approach to waste governance.