Why plastic ends up there and how to stop it. Stephen Ryan reports from the Ganges - a major source of plastic that ends up in the oceans. Manuela Saragosa speaks to Dr Hannah Ritchie of the Oxford University Martin School about the importance of plastic disposal. Professor Tony Ryan, a polymer chemist and sustainability leader at the University of Sheffield, explains why recycling is still the answer.

Producer: Laurence Knight

(Photo: A plastic bottle floating in the Pacific ocean, Credit: Getty Images)