Introduction: In Iran, rapid urbanization, economic development, and changing consumption patterns have resulted in increased waste generation. Current estimates indicate that average solid waste generation is approximately 0.63 kg per capita per day, highlighting the urgent need for effective waste management strategies to address this growing problem. The first stage of the integrated waste management hierarchy is source reduction, which, based on available studies, has received less attention compared to practices such as reuse and recycling. Accordingly, the current study aims to investigate the factors influencing waste reduction using the Theory of Planned Behavior.
Method: This research was conducted within a quantitative methodology framework, employing a survey approach. The study population consisted of all individuals aged 15 years and above in Abadan City, from which 395 participants were selected using multi-stage random sampling. The instruments used for measuring the variables were a researcher-developed questionnaire and a standardized instrument. To assess the validity of the waste reduction questionnaire, face and content validity were used, while reliability was evaluated using the test-retest method. The agreement coefficient between the initial test and retest was 0.91, indicating acceptable reliability for the questionnaire. Additionally, the construct validity of the environmental attitudes, subjective norms, and perceived behavioral control questionnaires was examined through confirmatory factor analysis, and their reliability was assessed using Cronbach's alpha.
Findings: The results revealed no significant relationship between environmental attitudes and waste reduction. However, both dimensions of subjective norms (descriptive and injunctive norms) demonstrated positive and significant relationships with waste reduction. The correlation coefficient between descriptive norms and waste reduction was higher than the correlation coefficient between injunctive norms and waste reduction. Furthermore, a significant relationship was found between perceived behavioral control and waste reduction. A positive and significant relationship was found between internal control and waste reduction, whereas a negative and significant relationship was found between external control and waste reduction. The average waste reduction differed significantly between single and married individuals and across different educational groups. The results from multiple regression analysis demonstrated that the study variables can account for 20% of the variance in waste reduction, with injunctive subjective norms and external perceived behavioral control exerting the greatest influence.
Conclusion: The findings of this research underscores the importance of subjective norms and perceived behavioral control in explaining waste reduction behavior. The special emphasis on the pronounces role of descriptive norms and the negative impact of external control offer valuable insights for designing effective interventions in waste management.