This study investigates the relationship between economic development and plastic pollution using the STIRPAT model, a stochastic regression model that incorporates population, affluence, and technology. The authors analyze a panel dataset of 128 countries from 1993 to 2017 to confirm the Environmental Kuznets Curve (EKC) relationship and explore the effects of sociodemographic factors on plastic pollution. The results show that the EKC hypothesis holds true, with plastic pollution increasing under business-as-usual (BAU) scenarios. Low-income countries and sub-Saharan Africa are projected to become major contributors to plastic pollution by 2050, leading to a global trend of increasing plastic pollution. The study also conducts scenario analyses to project plastic pollution under different conditions, such as slow GDP growth, changes in population structure, rapid urbanization, and urban primacy. These analyses highlight the sensitivity of projections to changes in assumptions and provide insights into policy implications. The findings suggest that policymakers should focus on low- and lower-middle-income countries, particularly sub-Saharan Africa, and consider a combination of regulatory, market-based, and behavioral instruments to reduce plastic pollution. High-income countries can play a crucial role in technological transfer and helping low-income countries manage urbanization. The study concludes by emphasizing the need for sustainable and growth-oriented policies to effectively address plastic pollution.This study investigates the relationship between economic development and plastic pollution using the STIRPAT model, a stochastic regression model that incorporates population, affluence, and technology. The authors analyze a panel dataset of 128 countries from 1993 to 2017 to confirm the Environmental Kuznets Curve (EKC) relationship and explore the effects of sociodemographic factors on plastic pollution. The results show that the EKC hypothesis holds true, with plastic pollution increasing under business-as-usual (BAU) scenarios. Low-income countries and sub-Saharan Africa are projected to become major contributors to plastic pollution by 2050, leading to a global trend of increasing plastic pollution. The study also conducts scenario analyses to project plastic pollution under different conditions, such as slow GDP growth, changes in population structure, rapid urbanization, and urban primacy. These analyses highlight the sensitivity of projections to changes in assumptions and provide insights into policy implications. The findings suggest that policymakers should focus on low- and lower-middle-income countries, particularly sub-Saharan Africa, and consider a combination of regulatory, market-based, and behavioral instruments to reduce plastic pollution. High-income countries can play a crucial role in technological transfer and helping low-income countries manage urbanization. The study concludes by emphasizing the need for sustainable and growth-oriented policies to effectively address plastic pollution.