20 April 2018: Data from the Deep-sea Debris Database found a plastic bag in the Mariana Trench, which is located 10,898 meters below the surface. According to the UN Environment Programme (UNEP, or UN Environment), this finding shows that human activities have affected the deepest part of the ocean.

Japan’s Agency for Marine-Earth Science and Technology’s Global Oceanographic Data Centre launched the Deep-sea Debris Database for public use in 2017. The database contains more than 30 years of photos and videos of debris that have been collected by remotely operated vehicles and deep-sea submersibles. Scientists, including from the UNEP-World Conservation Monitoring Center (WCMC), used this database to conduct a study, ‘Human footprint in the abyss: 30 year records of deep-sea plastic,’ which was published in the journal, ‘Marine Policy.’

The study found 3,435 pieces of manmade debris, including fishing gear, plastic, metal, and rubber, in the deep sea. Macro-plastic made up over one-third of the marine debris, 89% of which was single-use products. In areas of the ocean deeper than 6,000 meters, more than 50% of the debris was plastic and nearly all of it was single-use plastic. In addition, scientists observed deep-sea organisms in 17% of plastic debris images. UNEP cautions that plastic in the deep sea “can persist for thousands of years” and present threats to deep-sea ecosystems.

To address deep-sea plastic pollution, UNEP has called for reducing the production of plastic waste. The agency has also recommended a global monitoring network to share data on deep-sea plastic pollution and the development of ocean circulation models to identify how plastic travels from land to the deep sea, among other actions.

SDG Target 14.1 calls for, by 2025, preventing and significantly reducing marine pollution of all kinds, in particular from land-based activities, including marine debris and nutrient pollution. SDG 12 (responsible consumption and production) also includes targets focused on minimizing the adverse impacts of waste on human health and the environment. [UNEP Press Release] [Publication: Human footprint in the abyss: 30 year records of deep-sea plastic]