Is it true that 90 percent of the plastic in the oceans comes from 10 rivers in Asia and Africa?

You may read this claim frequently, but it is probably false. Such claims misquote the results of research published in 2017. In that study, scientists estimated how much plastic enters the sea from rivers around the world. Ten of these river systems carried most of the plastic, but plastic also reaches the sea in other ways – not just in rivers. So the total amount of plastic entering the ocean is higher than this riverine input alone. And new research suggests that a much larger number of rivers are carrying plastics to the sea.