How disgust sensitivity shapes waste disposal behavior in everyday public environments: Experimental and difference-in-differences studies in the Nordic countries

Disgust is an evolved emotion that helps humans avoid contamination, but it may also shape environmental behavior in everyday public settings. This study examines how disgust sensitivity and contamination cues influence improper household waste disposal. We theorize that unclean waste disposal areas evoke avoidance-oriented responses that reduce compliance with waste regulations. Three hypotheses are tested: that dirty environments increase improper disposal (situational effect), that individuals with higher disgust sensitivity are more likely to dispose improperly (trait effect), and that these factors interact (situational–trait effect). Evidence comes from three studies conducted in socioeconomically vulnerable Nordic neighborhoods: a quasi-experimental difference-in-differences study in Sweden, a survey experiment administered face-to-face in Sweden, and a survey experiment in Sweden, Finland, and Denmark. Across studies, dirtier disposal environments increased improper waste disposal, and higher disgust sensitivity was generally associated with lower compliance. Evidence for the interaction effect was mixed. The findings demonstrate that affective responses to contamination cues can undermine proper waste disposal behavior. Maintaining cleanliness at waste disposal sites may therefore be an effective way to support cooperative environmental behavior.