Does all the plastic in the ocean comes from 10 rivers only?

According to several websites publishing environmental news, including DW.com, 90 percent of all plastic found in the ocean comes from ten rivers only, eight in Asia and two in Africa. Plastic pollution is weighting heavily on the health of the ocean, disrupting its natural processes, which is especially problematic considering it is the main carbon sink of the planet and an essential source of nutrients for a throng of species, including human beings.