‘Rubbish found in deepest part of the ocean’

Human pollution has reached the deepest parts of the ocean, the scientist and former astronaut, Kathy Sullivan, has told BBC Hardtalk.

Expeditions run by Victor Vescovo have found traces of microplastics above background levels in animals living in the Mariana Trench, Dr Sullivan explained, as well as a fizzy drink can and fibre optic cables leftover from scientific explorations.

Dr Sullivan was the first US woman to walk in space in 1984 and recently became the first women to travel to the lowest known point in the ocean - the Challenger Deep, part of the Mariana Trench, some seven miles (11km) down - when she was invited on an expedition by Mr Vescovo.

Watch the full interview on BBC iPlayer (UK only)