Rivers are a major source of plastic waste into oceans. We estimate that between 1.15 and 2.41 million metric tons of plastic currently enters the ocean every year via rivers, with 86% of this global input coming from Asia.

This interactive map shows the results of a global numerical model that predicts inputs of plastics from rivers into the marine environment.

The map also depicts the data used by the model such as mismanaged plastic waste production on land, river catchment hydrology and location of dams and man-made barriers worldwide.

Our findings were published in Nature Communications and can assist in prioritizing future monitoring efforts and mitigation strategies.

Plastics in the marine environment have become a major concern because of their persistence at sea, and adverse consequences to marine life and potentially human health. Implementing mitigation strategies requires an understanding and quantification of marine plastic sources, taking spatial and temporal variability into account. Here we present a global model of plastic inputs from rivers into oceans based on waste management, population density and hydrological information.

Our model is calibrated against measurements available in the literature. We estimate that between 1.15 and 2.41 million tonnes of plastic waste currently enters the ocean every year from rivers, with over 74% of emissions occurring between May and October. The top 20 polluting rivers, mostly located in Asia, account for 67% of the global total. The findings of this study provide baseline data for ocean plastic mass balance exercises, and assist in prioritising future plastic debris monitoring and mitigation strategies.