Plastic pollution represents a major challenge for coastal cities in the Global South. This study quantifies the production, accumulation, and spatial distribution of plastic waste in the urban municipality of Toliara (southwestern Madagascar). Field surveys were conducted over an area of 24, 000 m² during two working weeks, covering residential, commercial, port, and coastal neighborhoods. The waste was sorted by functional typology, weighed separately, and analyzed using a Geographic Information System (GIS).
The results indicate an average production of 50 g of plastic per capita per day, equivalent to approximately 10 tons per day for an estimated population of 200, 000 inhabitants, corresponding to nearly 3, 650 tons per year. Single-use plastics dominate, while pollution hotspots are mainly located around markets, commercial areas, and the port. The overall accumulation is estimated at about 1, 200 tons.
These results provide novel quantitative data and a scientific basis for improving sustainable plastic waste management in Toliara.