Sustainable Cities and Plastic Waste: Innovation and Organizational Model of an Applied Case in Brazil

This article analyzes partnerships among the public sector, private companies, and waste pickers/cooperatives in urban plastic waste management, in light of the sustainable cities concept, assessing the economic, social, and environmental impacts of a reverse logistics arrangement involving schools and associations in southern Brazil and questioning its replicability and effectiveness. The methodology consisted of action research, with five years of data collection (2019–2024), combining document analysis, quantitative impact indicators, and qualitative discussion in light of theories of sustainable cities, circular economy, and associative models. The arrangement links a packaging industry, social collection entities, schools, and an independent technical verifier. Between 2019 and 2024, the model recycled 4.2 million PET bottles, benefited more than 60 schools and entities, reached more than 50,000 people, and transferred more than R$200,000 (≈US$40,000) to schools and recyclers, generating estimated savings of R$600,000 (≈US$120,000), with reductions of 152,000 kg CO2eq, 90,440 L of petroleum, 229,694 kWh, and 600,000 L of water, and up to a 100% reduction in waste compared with regular selective collection. The results indicate that this traceable model, anchored in environmental education and independent verification, can boost the local economy; whether and how it can be replicated in other cities remains a question for future comparative research rather than a claim established by this single case.