Waste separation behavior: A field study on information interventions and underlying mechanisms

Municipal waste generation exceeds 2 billion tons annually and is projected to rise 56% by 2050, intensifying environmental and resource recovery challenges. Even in countries with an advanced infrastructure like Germany, household waste sorting errors persist, undermining recycling efficiency. This study applies the Motivation-Opportunity-Ability (MOA) framework to examine behavioral drivers of sorting accuracy and to assess the effect of an information intervention. In a mixed-design field experiment with 102 households across socioeconomically diverse districts in Stuttgart, waste composition was measured before and after distributing an environmental flyer to the intervention group. Regression analyses revealed that structural factors-particularly limited access to collection points, system-inherent barriers, and knowledge-related barriers-significantly predicted sorting errors, while motivational variables had surprisingly no effect on sorting accuracy. The flyer intervention reduced errors across both socioeconomic groups, with flyer households showing a 69.7% reduction compared to 28.8% in the control group. Findings underscore the importance of addressing infrastructural and cognitive constraints alongside informational tools to improve waste separation systems. Well-designed flyers offer a cost-effective, scalable strategy to promote sustainable behavior, enhance recycling quality, and advance circular economy goals.