Determinants of source waste separation behavior in Iranian high school students: An application of the theory of planned behavior

Background: Nowadays, one of the most serious environmental concerns is the appropriate management and disposal of municipal waste, which can lead to significant environmental consequences. This study aimed to examine the determinants of source waste separation behavior (SWSB) among high school students applying the theory of planned behavior (TPB). Methods: In this descriptive study that was performed in 2022 via an online survey, 689 questionnaires were completed by students in 10 randomly selected high schools in Abhar, Iran. The data were analyzed by IBM SPSS Amos version 23. To assess the predictive determinants of SWSB, a structural equation model (SEM) was used. Results: Subjective norm was found to be the best predictor of high school students’ source waste separation (SWS) intention. The TPB had a prediction power of 68% and 74% for predicting waste separation from the source intention and behavior, respectively. Conclusion: According to the results of this study, subjective norm has the greatest impact on separation intentions (regression weight = 0.550; SE = 0.08; CR = 6.863; and P < 0.0001). Educational administrators are suggested to pay special attention to the role of significant others, such as teachers, parents, and peers in their planning to improve waste separation behavior at the source in schools.